diff --git a/.gitignore b/.gitignore
index fdd1235b0..bb3b410fc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,5 @@ src/cmd/stubs/phpstorm-stubs/
 y.output
 .idea
 vendor
+dev
+src/tests/golden/testdata/quickfix/*.fix
diff --git a/example/custom/custom_test.go b/example/custom/custom_test.go
index 082a15b3a..3b2e5e41b 100644
--- a/example/custom/custom_test.go
+++ b/example/custom/custom_test.go
@@ -11,6 +11,7 @@ func TestAssignmentAsExpression(t *testing.T) {
 	addCheckers(test.Config())
 
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	// PHPDoc annotations are not required for NoVerify in simple cases.
 	function something() {
 		$a = "test";
diff --git a/src/ir/irutil/keyword.go b/src/ir/irutil/keyword.go
index 764104929..8cf454865 100644
--- a/src/ir/irutil/keyword.go
+++ b/src/ir/irutil/keyword.go
@@ -14,6 +14,8 @@ func Keywords(n ir.Node) []*token.Token {
 	switch n := n.(type) {
 	case *ir.FunctionStmt:
 		return []*token.Token{n.FunctionTkn}
+	case *ir.DeclareStmt:
+		return []*token.Token{n.DeclareTkn}
 	case *ir.DefaultStmt:
 		return []*token.Token{n.DefaultTkn}
 	case *ir.CaseStmt:
diff --git a/src/linter/block_linter.go b/src/linter/block_linter.go
index bd7bc368d..6b163b8ce 100644
--- a/src/linter/block_linter.go
+++ b/src/linter/block_linter.go
@@ -57,6 +57,9 @@ func (b *blockLinter) enterNode(n ir.Node) {
 	case *ir.ExpressionStmt:
 		b.checkStmtExpression(n)
 
+	case *ir.DeclareStmt:
+		b.checkDeclareStrictTypes(n)
+
 	case *ir.ConstFetchExpr:
 		b.checkConstFetch(n)
 
@@ -547,7 +550,6 @@ func (b *blockLinter) checkNew(e *ir.NewExpr) {
 
 func (b *blockLinter) checkStmtExpression(s *ir.ExpressionStmt) {
 	report := false
-
 	// All branches except default try to filter-out common
 	// cases to reduce the number of type solving performed.
 	if irutil.IsAssign(s.Expr) {
@@ -1533,3 +1535,32 @@ func (b *blockLinter) classParseState() *meta.ClassParseState {
 func (b *blockLinter) metaInfo() *meta.Info {
 	return b.walker.r.ctx.st.Info
 }
+
+func (b *blockLinter) checkDeclareStrictTypes(statement *ir.DeclareStmt) {
+	if b.walker.r.strictTypes {
+		return
+	}
+
+	for _, i := range statement.Consts {
+		node, ok := i.(*ir.ConstantStmt)
+		if !ok {
+			return
+		}
+
+		if node.ConstantName.Value != "strict_types" {
+			return
+		}
+
+		value, isNumber := node.Expr.(*ir.Lnumber)
+		if !isNumber {
+			return
+		}
+
+		if value.Value == "1" {
+			return
+		}
+
+		b.report(statement, LevelWarning, "notStrictTypes", "strict_types value is not 1")
+		b.walker.r.addQuickFix("notStrictTypes", b.quickfix.StrictTypes(value))
+	}
+}
diff --git a/src/linter/quickfix.go b/src/linter/quickfix.go
index ef83aa8ad..b66b030a6 100644
--- a/src/linter/quickfix.go
+++ b/src/linter/quickfix.go
@@ -34,6 +34,22 @@ func (g *QuickFixGenerator) Array(arr *ir.ArrayExpr) quickfix.TextEdit {
 	}
 }
 
+func (g *QuickFixGenerator) StrictTypes(lnumber *ir.Lnumber) quickfix.TextEdit {
+	return quickfix.TextEdit{
+		StartPos:    lnumber.Position.StartPos,
+		EndPos:      lnumber.Position.EndPos,
+		Replacement: "1",
+	}
+}
+
+func (g *QuickFixGenerator) CreateDeclareStrictTypes(root *ir.Root) quickfix.TextEdit {
+	return quickfix.TextEdit{
+		StartPos:    root.Position.StartPos,
+		EndPos:      root.Position.StartPos,
+		Replacement: "declare(strict_types = 1);\n",
+	}
+}
+
 func (g *QuickFixGenerator) NullForNotNullableProperty(prop *ir.PropertyStmt) quickfix.TextEdit {
 	from := prop.Position.StartPos
 	to := prop.Variable.Position.EndPos
diff --git a/src/linter/report.go b/src/linter/report.go
index d1914da36..19b5d99ef 100644
--- a/src/linter/report.go
+++ b/src/linter/report.go
@@ -25,6 +25,24 @@ func addBuiltinCheckers(reg *CheckersRegistry) {
 			After:    `$s = strip_tags($s, '<br>')`,
 		},
 
+		{
+			Name:     "notStrictTypes",
+			Default:  true,
+			Quickfix: true,
+			Comment:  "Report strict_types value is not 1 in declare section.",
+			Before:   `declare(strict_types = 0);`,
+			After:    `declare(strict_types = 1);`,
+		},
+
+		{
+			Name:     "noDeclareSection",
+			Default:  true,
+			Quickfix: true,
+			Comment:  "Report declare(strict_types=1) has not been set.",
+			Before:   ` `,
+			After:    `declare(strict_types = 1);`,
+		},
+
 		{
 			Name:     "emptyStmt",
 			Default:  true,
@@ -1185,8 +1203,8 @@ func DiffReports(gitRepo string, diffArgs []string, changesList []git.Change, ch
 		}
 	}
 
-	old := reportListToMap(oldList)
-	new := reportListToMap(newList)
+	oldReportMap := reportListToMap(oldList)
+	newReportMap := reportListToMap(newList)
 	changes := gitChangesToMap(changesList)
 
 	var mu sync.Mutex
@@ -1196,7 +1214,7 @@ func DiffReports(gitRepo string, diffArgs []string, changesList []git.Change, ch
 
 	limitCh := make(chan struct{}, maxConcurrency)
 
-	for filename, list := range new {
+	for filename, list := range newReportMap {
 		wg.Add(1)
 		go func(filename string, list []*Report) {
 			limitCh <- struct{}{}
@@ -1212,7 +1230,7 @@ func DiffReports(gitRepo string, diffArgs []string, changesList []git.Change, ch
 				oldName = filename // full diff mode
 			}
 
-			reports, err := diffReportsList(gitRepo, ignoreCommits, diffArgs, filename, c, old[oldName], list)
+			reports, err := diffReportsList(gitRepo, ignoreCommits, diffArgs, filename, c, oldReportMap[oldName], list)
 			if err != nil {
 				mu.Lock()
 				resErr = err
@@ -1266,8 +1284,8 @@ func diffReportsList(gitRepo string, ignoreCommits map[string]struct{}, diffArgs
 		}
 	}
 
-	old, oldMaxLine := reportListToPerLineMap(oldList)
-	new, newMaxLine := reportListToPerLineMap(newList)
+	oldPerLineMap, oldMaxLine := reportListToPerLineMap(oldList)
+	newPerLineMap, newMaxLine := reportListToPerLineMap(newList)
 
 	var maxLine = oldMaxLine
 	if newMaxLine > maxLine {
@@ -1284,17 +1302,17 @@ func diffReportsList(gitRepo string, ignoreCommits map[string]struct{}, diffArgs
 		// just deletion
 		if ok && ch.new.HaveRange && ch.new.Range == 0 {
 			oldLine = ch.old.To
-			newLine-- // cancel the increment of newLine, because code was deleted, no new lines added
+			newLine-- // cancel the increment of newLine, because code was deleted, no newPerLineMap lines added
 			continue
 		}
 
-		res = maybeAppendReports(res, new, old, newLine, oldLine, blame, ignoreCommits)
+		res = maybeAppendReports(res, newPerLineMap, oldPerLineMap, newLine, oldLine, blame, ignoreCommits)
 
 		if ok {
 			oldLine = 0 // all changes and additions must be checked
 			for j := newLine + 1; j <= ch.new.To; j++ {
 				newLine = j
-				res = maybeAppendReports(res, new, old, newLine, oldLine, blame, ignoreCommits)
+				res = maybeAppendReports(res, newPerLineMap, oldPerLineMap, newLine, oldLine, blame, ignoreCommits)
 			}
 			oldLine = ch.old.To
 		}
diff --git a/src/linter/root.go b/src/linter/root.go
index 3c23699ac..414e23c3f 100644
--- a/src/linter/root.go
+++ b/src/linter/root.go
@@ -69,10 +69,12 @@ type rootWalker struct {
 	// name matches the pattern and @linter disable was encountered
 
 	// strictTypes is true if file contains `declare(strict_types=1)`.
-	strictTypes bool
-	strictMixed bool
+	strictTypes    bool
+	strictMixed    bool
+	declareSection bool
 
-	reports []*Report
+	reports  []*Report
+	quickfix *QuickFixGenerator
 
 	config *Config
 
@@ -141,7 +143,12 @@ func (d *rootWalker) EnterNode(n ir.Node) (res bool) {
 			}
 			if c.ConstantName.Value == "strict_types" {
 				v, ok := c.Expr.(*ir.Lnumber)
-				if ok && v.Value == "1" {
+				if !ok {
+					continue
+				}
+
+				d.declareSection = true
+				if v.Value == "1" {
 					d.strictTypes = true
 				}
 			}
diff --git a/src/linter/worker.go b/src/linter/worker.go
index 6cfa8c5a0..8e7beb7cd 100644
--- a/src/linter/worker.go
+++ b/src/linter/worker.go
@@ -315,6 +315,11 @@ func (w *Worker) analyzeFile(file *workspace.File, rootNode *ir.Root) (*rootWalk
 	}
 	walker.afterLeaveFile()
 
+	if !walker.declareSection {
+		walker.Report(rootNode, LevelWarning, "noDeclareSection", "Missed declare(strict_types=1) directive")
+		walker.addQuickFix("notStrictTypes", walker.quickfix.CreateDeclareStrictTypes(rootNode))
+	}
+
 	if len(walker.ctx.fixes) != 0 {
 		needApplyFixes := !file.AutoGenerated() || w.config.CheckAutoGenerated
 
diff --git a/src/tests/checkers/anon_class_test.go b/src/tests/checkers/anon_class_test.go
index 654a9d9fb..8f5951a69 100644
--- a/src/tests/checkers/anon_class_test.go
+++ b/src/tests/checkers/anon_class_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestSimpleAnonClass(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+		declare(strict_types = 1);
 function f() {
   $a = new class {
     /** */
@@ -21,6 +22,7 @@ function f() {
 
 func TestAnonClassAsInterface(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 interface IFace {}
 
 function f(IFace $if) {}
@@ -32,6 +34,7 @@ f(new class implements IFace {});
 func TestAnonClassFromDocumentation(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 class Outer {
   private $prop = 1;
   protected $prop2 = 2;
@@ -66,6 +69,7 @@ echo (new Outer)->func2()->func3();
 
 func TestAnonClassWithConstructor(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 function f() {
   $a = new class(100, "s") {
     /** */
@@ -84,6 +88,7 @@ function f() {
 
 func TestAnonClassWithExtends(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 class Boo {
   /** */
   public function b() {}
@@ -103,6 +108,7 @@ function f() {
 
 func TestAnonClassWithImplements(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 interface IBoo {
   /** */
   public function b() {}
@@ -121,6 +127,8 @@ function f() {
 
 func TestAnonClassWithSeveralImplements(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
+
 interface IBoo {
   /** */
   public function b() {}
diff --git a/src/tests/checkers/arrow_functions_test.go b/src/tests/checkers/arrow_functions_test.go
index 760f9ef98..e33c15fe9 100644
--- a/src/tests/checkers/arrow_functions_test.go
+++ b/src/tests/checkers/arrow_functions_test.go
@@ -9,6 +9,7 @@ import (
 func TestArrowFunction(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 class Boo {
   /** @return int */
   public function b() { }
@@ -94,6 +95,8 @@ func TestUnusedInArrowFunction(t *testing.T) {
 		`stubs/phpstorm-stubs/standard/standard_9.php`,
 	}
 	test.AddFile(`<?php
+	declare(strict_types = 1);
+
 function f() {
   $a1 = [];
   $a2 = [];
diff --git a/src/tests/checkers/basic_test.go b/src/tests/checkers/basic_test.go
index 3594f26c9..19d3d8196 100644
--- a/src/tests/checkers/basic_test.go
+++ b/src/tests/checkers/basic_test.go
@@ -15,6 +15,8 @@ import (
 func TestBadString(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
+
 $_ = "\u{";
 $_ = "\u{zzzz}";
 `)
@@ -27,6 +29,7 @@ $_ = "\u{zzzz}";
 
 func TestStringNoQuotes(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 $arr = [];
 echo "$arr[key]\n";
 `)
@@ -37,6 +40,7 @@ func TestIntOverflow(t *testing.T) {
 
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 // Overflow cases.
 echo -9223372036854775808;
 echo 9223372036854775808;
@@ -63,6 +67,7 @@ echo -9.2233720368548E+18;
 
 func TestDupGlobalRoot(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 global $x;
 global $x;
 `)
@@ -70,6 +75,7 @@ global $x;
 
 func TestDupGlobalCond(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function both_conditional($cond1, $cond2) {
   if ($cond1) {
     global $x3;
@@ -87,6 +93,7 @@ function both_conditional($cond1, $cond2) {
 func TestDupGlobalSameStatement(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f1($cond) {
   if ($cond) {
     // global is conditional, but contains local duplicates.
@@ -101,6 +108,7 @@ function f1($cond) {
 func TestDupGlobal(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f1() {
   global $x1, $x1;
   return $x1;
@@ -130,6 +138,7 @@ function f3() {
 func TestRedundantGlobal(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $foo = 0;
 
 function f1() {
@@ -157,6 +166,7 @@ function f2() {
 func TestForeachEmpty(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $xs = [];
 foreach ($xs as $k => $v) {
   $_ = [$k, $v];
@@ -178,6 +188,7 @@ $_ = [$x]; // Bad
 func TestForeachSimplify(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
     $x = [];
 
@@ -200,6 +211,7 @@ function f() {
 func TestBareTry(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 try {
   echo 123;
 }
@@ -214,6 +226,7 @@ func TestLinterDisableUnmatchedFilename(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AllowDisable = regexp.MustCompile(`will match nothing`)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @linter disable */
 $_ = array(1);
 `)
@@ -228,6 +241,7 @@ func TestLinterDisable(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AllowDisable = regexp.MustCompile(`.*`)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @linter disable */
 $_ = array(1);
 `)
@@ -238,6 +252,7 @@ func TestLinterDisableTwice(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AllowDisable = regexp.MustCompile(`.*`)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @linter disable */
 $_ = array(1);
 /** @linter disable */
@@ -251,6 +266,7 @@ $_ = array(1);
 func TestMultiplyLinterDisable(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @linter disable */
 $_ = array(1);
 
@@ -283,6 +299,7 @@ func TestKeywordCaseElseif(t *testing.T) {
 	test := linttest.NewSuite(t)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($cond) {
   if ($cond+0) {
   } Else  If ($cond+1) {
@@ -462,6 +479,7 @@ func TestCallStaticParent(t *testing.T) {
 func TestVoidResultUsedInAssignment(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	/**
 	* @return void
 	*/
@@ -477,6 +495,7 @@ func TestVoidResultUsedInAssignment(t *testing.T) {
 func TestVoidResultUsedInBinary(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	/**
 	 * @return void
 	 */
@@ -538,6 +557,7 @@ func TestVoidResultUsedInBinary(t *testing.T) {
 func TestVoidForParamAndReturn(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
 * @param void $x
 * @param int $y
@@ -579,7 +599,7 @@ func TestCallStatic(t *testing.T) {
 
 func TestForeachList(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
-
+declare(strict_types = 1);
 foreach ([[1, 2]] as list($x, $y)) {
   $_ = [$x => $y];
 }
@@ -593,6 +613,7 @@ foreach ([[1, 2, 3, 4]] as list($x, $y,,$z)) {
 func TestArgsCount(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
 $_ = mt_rand();        // OK
 $_ = mt_rand(1);       // Not OK
@@ -611,6 +632,7 @@ function mt_rand($x = 0, $y = 0) { return 1; }`)
 func TestArgsArraysSyntax(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function bad($a = array()) {}
 function good($a = []) {}
 `)
@@ -623,7 +645,7 @@ function good($a = []) {}
 func TestMethodComplexity(t *testing.T) {
 	funcCode := strings.Repeat("$_ = 0;\n", 9999)
 	test := linttest.NewSuite(t)
-	test.AddFile(`<?php class C { private function f() {` + funcCode + `} }`)
+	test.AddFile(`<?php declare(strict_types = 1); class C { private function f() {` + funcCode + `} }`)
 	test.Expect = []string{"Too big method: more than 150"}
 	test.RunAndMatch()
 }
@@ -631,13 +653,14 @@ func TestMethodComplexity(t *testing.T) {
 func TestFuncComplexity(t *testing.T) {
 	funcCode := strings.Repeat("$_ = 0;\n", 9999)
 	test := linttest.NewSuite(t)
-	test.AddFile(`<?php function f() {` + funcCode + `}`)
+	test.AddFile(`<?php declare(strict_types = 1); function f() {` + funcCode + `}`)
 	test.Expect = []string{"Too big function: more than 150"}
 	test.RunAndMatch()
 }
 
 func TestPrecedenceGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function foo() { return 10; }
 
 function rhs($x, $mask) {
@@ -721,17 +744,19 @@ class Foo {
 
 func TestAutogenSkip(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // auto-generated file, DO NOT EDIT!
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // auto-generated file
 // DO NOT EDIT!
 
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
-
+declare(strict_types = 1);
 /*
  * AUTO-GENERATED
  *
@@ -741,28 +766,33 @@ $_ = array();`)
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // autogenerated (DO NOT EDIT)
 
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 /* autogenerated (DO NOT EDIT) */
 
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // File generated by foobar.
 // Do not edit (re-run generator instead).
 
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // Do not edit this file.
 // It's auto-generated.
 
 $_ = array();`)
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // This file is auto-generated.
 //
 // This comment contains a few extra lines of text.
@@ -775,6 +805,7 @@ $_ = array();`)
 
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $_ = "autogenerated; do not edit";
 
 $_ = array();`)
@@ -786,6 +817,7 @@ $_ = array();`)
 
 func TestAssignmentsInForLoop(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function increment($i) { return $i + 1; }
 
 for ($i = 0; $i <= 10; $i = increment($i)) {}
@@ -807,6 +839,7 @@ func TestCustomUnusedVarRegex(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.UseConfig(config)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   public $_;
   private $_foo;
@@ -823,6 +856,8 @@ $_ = __FILE__;
 	test = linttest.NewSuite(t)
 	test.UseConfig(config)
 	test.AddFile(`<?php
+declare(strict_types = 1);
+
 $_unused = 10;
 
 function f() {
@@ -839,6 +874,7 @@ function f() {
 	test = linttest.NewSuite(t)
 	test.UseConfig(config)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function var_dump($v) {}
 $_global = 120;
 function f() {
@@ -868,6 +904,7 @@ var_dump($_global);
 func TestDiscardVarUsage(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function var_dump($v) {}
 function f() {
   $_ = 1;
@@ -896,6 +933,7 @@ var_dump($_); // 6. Also forbidden in global scope
 
 func TestDiscardVarNotUsage(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function foo(): int { return 0; }
 
 function f() {
@@ -910,6 +948,7 @@ function f() {
 
 func TestOrDie1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 global $ok;
 $ok or die("not ok");
 echo "quite reachable\n";
@@ -920,6 +959,7 @@ func TestOrDie2(t *testing.T) {
 	// Check that we still check "or" LHS and RHS properly.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $undef1 or die($undef2);
 `)
 	test.Expect = []string{
@@ -931,6 +971,7 @@ $undef1 or die($undef2);
 
 func TestOrExit(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 global $ok;
 $ok or exit("");
 echo "quite reachable\n";
@@ -939,6 +980,7 @@ echo "quite reachable\n";
 
 func TestUnusedInInstanceof(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {}
 
 function f1($cond) {
@@ -972,6 +1014,7 @@ function f3() {
 
 func TestUnusedInVarPropFetch(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {}
 function foo(Foo $x) {
 	$y = "propname";
@@ -982,6 +1025,7 @@ function foo(Foo $x) {
 
 func TestUnusedInVarPropAssign(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {}
 function foo(Foo $x) {
 	$y = "propname";
@@ -993,6 +1037,7 @@ function foo(Foo $x) {
 func TestStaticPropFetch(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 function foo() {
 	$x = "propname";
@@ -1008,6 +1053,7 @@ function foo() {
 
 func TestUnusedInStaticVarPropFetch(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {}
 function foo() {
 	$x = "propname";
@@ -1018,6 +1064,7 @@ function foo() {
 
 func TestUnusedInStaticVarPropAssign(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {}
 function foo() {
 	$x = "propname";
@@ -1126,6 +1173,7 @@ func TestSwitchContinue1(t *testing.T) {
 func TestSwitchContinue2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	global $x;
 	switch ($x) {
 	case 10:
@@ -1160,6 +1208,7 @@ func TestSwitchContinue2(t *testing.T) {
 func TestBuiltinConstant(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	function f() {
 		$_ = NULL;
 		$_ = True;
@@ -1178,6 +1227,7 @@ func TestBuiltinConstant(t *testing.T) {
 
 func TestFunctionNotOnlyExits2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 	function rand() {
 		return 4;
 	}
@@ -1204,6 +1254,7 @@ func TestFunctionNotOnlyExits2(t *testing.T) {
 func TestArrayAccessForClass(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	class three {}
 	class five {}
 	function test() {
@@ -1219,6 +1270,7 @@ func TestArrayAccessForClass(t *testing.T) {
 // that does not implement ArrayAccess.
 func TestCorrectTypes(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 	class three {}
 	class five {}
 	function test() {
@@ -1230,6 +1282,7 @@ func TestCorrectTypes(t *testing.T) {
 
 func TestAllowReturnAfterUnreachable(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function unreachable() {
 		exit;
 	}
@@ -1242,6 +1295,7 @@ func TestAllowReturnAfterUnreachable(t *testing.T) {
 
 func TestFunctionReferenceParams(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function doSometing(&$result) {
 		$result = 5;
 	}`)
@@ -1250,6 +1304,7 @@ func TestFunctionReferenceParams(t *testing.T) {
 func TestFunctionReferenceParamsInAnonymousFunction(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function doSometing() {
 		return function() use($a, &$result) {
 			echo $a;
@@ -1262,6 +1317,7 @@ func TestFunctionReferenceParamsInAnonymousFunction(t *testing.T) {
 
 func TestFunctionCallSplatArg(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function doSomething($a, $b, $c) {}
 $x = [1, 2, 3];
 doSomething(...$x);
@@ -1270,6 +1326,7 @@ doSomething(...$x);
 
 func TestForeachByRef(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 $xs = [1, 2];
 foreach ($xs as &$x) {
     if ($x) {
@@ -1284,6 +1341,7 @@ foreach ($xs as &$x) {
 
 func TestForeachByRefUnused(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 	class SomeClass {
 		public $a;
 	}
@@ -1307,6 +1365,7 @@ func TestForeachByRefUnused(t *testing.T) {
 
 func TestAllowAssignmentInForLoop(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 	function test() {
 	  for ($day = 0; $day <= 100; $day = $day + 1) {
 		echo $day;
@@ -1318,6 +1377,7 @@ func TestAllowAssignmentInForLoop(t *testing.T) {
 func TestDuplicateArrayKeyEscapes(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $_ = ["\n" => 1, "\xa" => 2];
 `)
 	test.Expect = []string{`Duplicate array key "\n"`}
@@ -1326,6 +1386,7 @@ $_ = ["\n" => 1, "\xa" => 2];
 
 func TestDuplicateArrayKeyGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 $valid_quotes = [
   '"' => 1,
   "'" => 1,
@@ -1336,6 +1397,7 @@ $valid_quotes = [
 func TestDuplicateArrayKey(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function test() {
   return [
 	  'key1' => 'something',
@@ -1351,6 +1413,7 @@ function test() {
 func TestDuplicateArrayKeyWithBoolConstants(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 define('TRUE_CONST', true);
 define('FALSE_CONST', false);
 
@@ -1371,6 +1434,7 @@ $_ = [1 => 1, true => 2];
 func TestDuplicateArrayKeyWithConstants(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 const MAX_VALUE = 1;
 const MIN_VALUE = 0+1; // Const-folded to 1
 $a = [
@@ -1422,6 +1486,7 @@ $b = [
 func TestMixedArrayKeys(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	function test() {
 	  return [
 		  'something',
@@ -1437,6 +1502,7 @@ func TestMixedArrayKeys(t *testing.T) {
 func TestStringGlobalVarName(t *testing.T) {
 	// Should not panic.
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function f() {
 		global ${"x"};
 		global ${"${x}_{$x}"};
@@ -1446,6 +1512,7 @@ func TestStringGlobalVarName(t *testing.T) {
 func TestArrayLiteral(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function traditional_array_literal() {
 		return array(1, 2);
 	}`)
@@ -1455,6 +1522,7 @@ func TestArrayLiteral(t *testing.T) {
 
 func TestNonEmptyVar(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function non_empty_var() {
 		if (!empty($x)) {
 			return $x;
@@ -1473,6 +1541,7 @@ func TestEmptyVar(t *testing.T) {
 
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function empty_var() {
 		if (empty($x1)) {
 			return $x1;
@@ -1495,6 +1564,7 @@ func TestEmptyVar(t *testing.T) {
 func TestIssetElseif1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
   if (isset($x)) {
     echo $x;
@@ -1510,6 +1580,7 @@ function f() {
 
 func TestIssetElseif2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 if (isset($x)) {
   echo $x;
 } else if (isset($y)) {
@@ -1520,6 +1591,7 @@ if (isset($x)) {
 func TestUnused(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function unused_test($arg1, $arg2) {
 		global $g;
 
@@ -1543,6 +1615,7 @@ func TestUnused(t *testing.T) {
 func TestAtVar(t *testing.T) {
 	// variables declared using @var should not be overridden
 	result := linttest.CheckFile(t, `<?php
+	declare(strict_types = 1);
 	function test() {
 		/** @var string $a */
 		$a = true;
@@ -1579,7 +1652,9 @@ func TestAtVar(t *testing.T) {
 
 func TestFunctionExit(t *testing.T) {
 	test := linttest.NewSuite(t)
-	test.AddFile(`<?php function doExit() {
+	test.AddFile(`<?php 
+	declare(strict_types = 1);
+	function doExit() {
 		exit;
 	}
 
@@ -1593,7 +1668,9 @@ func TestFunctionExit(t *testing.T) {
 
 func TestFunctionDie(t *testing.T) {
 	test := linttest.NewSuite(t)
-	test.AddFile(`<?php function doDie() {
+	test.AddFile(`<?php
+	declare(strict_types = 1);
+	function doDie() {
 		die("123");
 		echo "Also unreachable";
 	}
@@ -1610,7 +1687,9 @@ func TestFunctionDie(t *testing.T) {
 }
 
 func TestFunctionNotOnlyExits(t *testing.T) {
-	linttest.SimpleNegativeTest(t, `<?php function rand() {
+	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
+	function rand() {
 		return 4;
 	}
 
@@ -1629,7 +1708,9 @@ func TestFunctionNotOnlyExits(t *testing.T) {
 }
 
 func TestFunctionJustReturns(t *testing.T) {
-	linttest.SimpleNegativeTest(t, `<?php function justReturn() {
+	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
+	function justReturn() {
 		return 1;
 	}
 
@@ -1641,6 +1722,7 @@ func TestFunctionJustReturns(t *testing.T) {
 
 func TestSwitchFallthrough(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function withFallthrough($a) {
 		switch ($a) {
 		case 1:
@@ -1664,6 +1746,7 @@ func TestSwitchFallthrough(t *testing.T) {
 
 func TestFunctionThrowsExceptionsAndReturns(t *testing.T) {
 	result := linttest.CheckFile(t, `<?php
+	declare(strict_types = 1);
 	class Exception {}
 
 	function handle($b) {
@@ -1704,6 +1787,7 @@ func TestFunctionThrowsExceptionsAndReturns(t *testing.T) {
 func TestRedundantCast(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function bad($a) {
 		$int = 1;
 		$double = 1.0;
@@ -1744,6 +1828,7 @@ func TestRedundantCast(t *testing.T) {
 func TestSwitchBreak(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function bad($a) {
 		switch ($a) {
 		case 2:
@@ -1904,6 +1989,7 @@ class A extends B {
 func TestClassNotFound(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $_ = new Foo();
 
 class Derived extends Base {}
@@ -2003,6 +2089,7 @@ func TestArrayUnion(t *testing.T) {
 
 func TestCompactImpliesUsage(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 // Declaration from phpstorm-stubs
 function compact ($varname, $_ = null) {}
 
@@ -2040,6 +2127,7 @@ function f() {
 
 func TestAssignByRef(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function a() {
 	  $a = 1;
 	  $b = &$a;
@@ -2053,6 +2141,7 @@ func TestAssignByRef(t *testing.T) {
 func TestUndefinedConst(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 echo UNDEFINED_CONST;
 `)
 	test.Expect = []string{`Undefined constant UNDEFINED_CONST`}
@@ -2062,6 +2151,7 @@ echo UNDEFINED_CONST;
 func TestTrailingCommaForArray(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
     $_ = [10, 20, 30]; // ok
 
@@ -2105,6 +2195,7 @@ function f() {
 func TestNestedTernary(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
     $_ = 1 ? 2 : 3 ? 4 : 5; // error
 	//   |_______|
@@ -2134,6 +2225,7 @@ function f() {
 func TestRealCastingAndIsRealCall(t *testing.T) {
 	test := linttest.NewPHP7Suite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function is_real($a): bool { return true; }
 
 function f() {
@@ -2153,6 +2245,7 @@ function f() {
 func TestArrayKeyExistCallWithObject(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function array_key_exists($a, $b): bool { return true; }
 
 class Foo {}
@@ -2190,6 +2283,7 @@ function f() {
 func TestRandomIntWrongArgsOrder(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function random_int($min, $max) { return 0; }
 
 const AA = 99;
@@ -2222,6 +2316,7 @@ function f() {
 
 func TestDefineWithTrailingSlash(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 \define('ONE', 1);
 define('TWO', 1);
 
@@ -2233,6 +2328,7 @@ echo TWO;
 func TestComplexInstanceOf(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Boo {
   /** @return int */
   public function b() { return 0; }
@@ -2253,6 +2349,7 @@ function f($a) {
 func TestVarsInTernary(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Boo {}
 
 function f($a) {
@@ -2280,6 +2377,7 @@ function f($a) {
 
 func TestIfCondAssign(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f1($v) {
   if ($x = $v) {}
   echo $x;
@@ -2297,6 +2395,7 @@ function f2($v) {
 func TestElseIf1CondAssign(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f1($v) {
   if ($v) {
   } elseif ($x = 10) {}
@@ -2323,6 +2422,7 @@ function f2($v) {
 func TestElseIf2CondAssign(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f1($v) {
   if ($v) {
   } else if ($x = 10) {}
@@ -2347,6 +2447,7 @@ function f2($v) {
 func TestUndefinedVariableInCoalesceOrIsset(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
   if (1) {
     $a = 100;
diff --git a/src/tests/checkers/catch_test.go b/src/tests/checkers/catch_test.go
index 2a9217f49..4554f66d9 100644
--- a/src/tests/checkers/catch_test.go
+++ b/src/tests/checkers/catch_test.go
@@ -9,6 +9,7 @@ import (
 func TestCatchDup(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class MyException1 extends Exception {}
 class MyException2 extends Exception {}
 
@@ -25,6 +26,7 @@ try {
 func TestCatchOrderThrowable(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 try {
 } catch (Throwable $e) {
 } catch (Exception $e) {
@@ -37,6 +39,7 @@ try {
 func TestCatchOrderExtends(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class MyException extends Exception {}
 
 try {
@@ -53,6 +56,7 @@ try {
 func TestCatchOrderExtends2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class ExceptionBase extends Exception {}
 class ExceptionDerived extends ExceptionBase {}
 
@@ -69,6 +73,7 @@ try {
 
 func TestCatchOrderExtendsGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class ExceptionBase extends Exception {}
 class ExceptionDerived extends ExceptionBase {}
 
@@ -82,6 +87,7 @@ try {
 func TestCatchOrderImplements(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 interface CustomException {}
 
 class ExceptionBase extends Exception implements CustomException {}
@@ -102,6 +108,7 @@ try {
 
 func TestCatchOrderImplementsGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 interface CustomException {}
 
 class ExceptionBase extends Exception implements CustomException {}
@@ -118,6 +125,7 @@ try {
 func TestTryCatchVariables(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class ExceptionDerived extends Exception {}
 
 function f() {
@@ -171,6 +179,7 @@ function f() {
 func TestTryCatchVariablesWithExit(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class ExceptionDerived extends Exception {}
 
 function f() {
@@ -230,6 +239,7 @@ function f() {
 func TestCatchWithoutVariable(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 try {}
 catch (Exception) {}
 `)
diff --git a/src/tests/checkers/closure_test.go b/src/tests/checkers/closure_test.go
index 647d597d6..da1e89f8a 100644
--- a/src/tests/checkers/closure_test.go
+++ b/src/tests/checkers/closure_test.go
@@ -9,6 +9,7 @@ import (
 func TestClosureCapture(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class omg {
   public $some_property;
 }
@@ -29,6 +30,7 @@ function doSomething($a, omg $b) {
 func TestClosureDoc(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /**
    * @return int
@@ -54,6 +56,7 @@ function f(callable $s) {
 func TestClosureInvalidDoc(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 
 /**
diff --git a/src/tests/checkers/codedup_test.go b/src/tests/checkers/codedup_test.go
index 0842d2c4e..3ee1f5f1c 100644
--- a/src/tests/checkers/codedup_test.go
+++ b/src/tests/checkers/codedup_test.go
@@ -9,6 +9,7 @@ import (
 func TestDupSubExpr1(t *testing.T) {
 	// Operations below are not checked by dupSubExpr.
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f($x) {
   $_ = [
     $x + $x,
@@ -23,6 +24,7 @@ func TestDupSubExpr2(t *testing.T) {
 	// All expression below give warnings for mixed-typed values.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($x) {
   $_ = [
     $x & $x, // 1
@@ -77,6 +79,7 @@ func TestDupSubExpr3(t *testing.T) {
 	// Duplicated expression is float-typed.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
   $x = 1.5;
   $_ = [
@@ -122,6 +125,7 @@ function f() {
 func TestDupTernaryOperands(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($cond) {
   return $cond ? 1 : 1;
 }
@@ -142,6 +146,7 @@ function f2($cond) {
 func TestDupIfElseBody(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($cond) {
   if ($cond) {
     return 0;
@@ -197,6 +202,7 @@ function f2($cond) {
 func TestDupIfCond1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 const C1 = 1;
 const C2 = 2;
 const C3 = 3;
@@ -250,6 +256,7 @@ function f($cond) {
 
 func TestDupIfCond2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f($cond) {
   if ($cond+1) {
     if ($cond+1) {
diff --git a/src/tests/checkers/deprecated_test.go b/src/tests/checkers/deprecated_test.go
index a7ddfd669..197746a40 100644
--- a/src/tests/checkers/deprecated_test.go
+++ b/src/tests/checkers/deprecated_test.go
@@ -9,6 +9,7 @@ import (
 func TestDeprecatedWithoutText(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class WithoutText {
   /**
    * @deprecated
@@ -42,6 +43,7 @@ WithoutText::staticMethod();
 func TestDeprecatedWithText(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class WithText {
   /**
    * @deprecated use method2() instead
diff --git a/src/tests/checkers/disable_inspection_test.go b/src/tests/checkers/disable_inspection_test.go
index 495863650..9e7353e99 100644
--- a/src/tests/checkers/disable_inspection_test.go
+++ b/src/tests/checkers/disable_inspection_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestDisableDeadCode(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f() {
 #ifndef KPHP
   return 1;
diff --git a/src/tests/checkers/discard_expr_test.go b/src/tests/checkers/discard_expr_test.go
index 06acb58fc..c509ed885 100644
--- a/src/tests/checkers/discard_expr_test.go
+++ b/src/tests/checkers/discard_expr_test.go
@@ -28,6 +28,7 @@ $dom->loadHTML('<meta http-equiv="Content-Type" content="text/html; charset=UTF-
 
 func TestDiscardExprVariableCall(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function local1($xs) {
   // It does discard the result, but we're not tracking
   // variable function calls yet.
@@ -59,6 +60,7 @@ function local4($xs) {
 
 func TestDiscardExprAbstractCall(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 abstract class TheAbstractClass {
   /** @return bool */
   abstract public function doIt();
@@ -81,6 +83,7 @@ useAbstract($c);
 
 func TestDiscardExprInterfaceCall(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 interface TheInterface {
   /** @return bool */
   public function load($x);
@@ -163,6 +166,7 @@ pure_fn1(1, 2); // warn 4
 func TestDiscardExpr(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class C {}
 
 function count($xs) { return 0; }
diff --git a/src/tests/checkers/emptystmt_test.go b/src/tests/checkers/emptystmt_test.go
index ea6919375..17fd8e448 100644
--- a/src/tests/checkers/emptystmt_test.go
+++ b/src/tests/checkers/emptystmt_test.go
@@ -9,6 +9,7 @@ import (
 func TestEmptyStmtBadComment(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @var $foo int */;
 global $foo;
 `)
@@ -21,6 +22,7 @@ global $foo;
 func TestEmptyStmtBadStmtEnd(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 if ($argv) {
 };
 while ($argv) {
@@ -38,6 +40,7 @@ class Foo {};
 func TestEmptyStmtBadRequire1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 require_once 'foo.php';;
 `)
 	test.Expect = []string{
@@ -49,6 +52,7 @@ require_once 'foo.php';;
 func TestEmptyStmtBadRequire2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 require_once 'foo.php'; ; ;
 `)
 	test.Expect = []string{
@@ -61,6 +65,7 @@ require_once 'foo.php'; ; ;
 func TestEmptyStmtBadStmtSeparator(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 echo 1;
 ; echo 2;
 echo 3; ;
@@ -74,6 +79,7 @@ echo 3; ;
 
 func TestEmptyStmtScriptEnd1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f() {}
 ?>
 `)
@@ -81,6 +87,7 @@ function f() {}
 
 func TestEmptyStmtScriptEnd2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 echo 123;
 ?>
 `)
diff --git a/src/tests/checkers/function_exists_test.go b/src/tests/checkers/function_exists_test.go
index ab1b3173d..05b293e31 100644
--- a/src/tests/checkers/function_exists_test.go
+++ b/src/tests/checkers/function_exists_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestFunctionExists1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function function_exists($name) { return 1 == 2; }
 
 if (function_exists('\foo')) {
@@ -28,6 +29,7 @@ if (function_exists('a\b\baz')) {
 func TestFunctionExists2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function function_exists($name) { return 1 == 2; }
 
 function f($cond) {
@@ -53,6 +55,7 @@ function f($cond) {
 func TestFunctionExists3(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function function_exists($name) { return 1 == 2; }
 
 if (function_exists('\foo')) {
diff --git a/src/tests/checkers/get_type_miss_use_test.go b/src/tests/checkers/get_type_miss_use_test.go
index eadfa2639..6d3a0ac83 100644
--- a/src/tests/checkers/get_type_miss_use_test.go
+++ b/src/tests/checkers/get_type_miss_use_test.go
@@ -12,6 +12,7 @@ func TestGettypeFunction(t *testing.T) {
 		`stubs/phpstorm-stubs/standard/standard_5.php`,
 	}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function getTypeMisUse(mixed $var) {
   if (gettype($var) === "string") {
   }
diff --git a/src/tests/checkers/indexing_order_test.go b/src/tests/checkers/indexing_order_test.go
index ec7c4b5f2..4abb979b5 100644
--- a/src/tests/checkers/indexing_order_test.go
+++ b/src/tests/checkers/indexing_order_test.go
@@ -18,11 +18,13 @@ func TestIndexingOrderClasses(t *testing.T) {
 
 	test := linttest.NewSuite(t)
 	test.AddNamedFile("/foo/A.php", `<?php
+declare(strict_types = 1);
 class A {}
 
 $v = new A();
 `)
 	test.AddNamedFile("/bar/A.php", `<?php
+declare(strict_types = 1);
 class A {
   public $field;
   public function __construct($x) { $this->field = $x; }
@@ -44,6 +46,7 @@ echo $v->field;
 func TestIndexingOrderTraits(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddNamedFile("/foo/A.php", `<?php
+declare(strict_types = 1);
 trait TA {}
 
 class A { use TA; }
@@ -51,6 +54,7 @@ class A { use TA; }
 $v = new A();
 `)
 	test.AddNamedFile("/bar/A.php", `<?php
+declare(strict_types = 1);
 trait TA {
   public $field;
   public function __construct($x) { $this->field = $x; }
@@ -76,11 +80,13 @@ echo $v->field;
 func TestIndexingOrderFuncs(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddNamedFile("/foo/A.php", `<?php
+declare(strict_types = 1);
 function a() {}
 
 a();
 `)
 	test.AddNamedFile("/bar/A.php", `<?php
+declare(strict_types = 1);
 function a($x) {}
 
 a(1);
diff --git a/src/tests/checkers/kphp_test.go b/src/tests/checkers/kphp_test.go
index 7b0caa33d..46114bbb5 100644
--- a/src/tests/checkers/kphp_test.go
+++ b/src/tests/checkers/kphp_test.go
@@ -10,6 +10,7 @@ func TestArrayAccessForAny(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().KPHP = true
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	/** @return any */
 	function get_any() {
 		return [];
@@ -23,6 +24,7 @@ func TestDifferentTypesAsUndefinedClass(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().KPHP = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @param tuple(int, string) $a
  * @param shape(key: int, val: string) $b
diff --git a/src/tests/checkers/linter_suppress_test.go b/src/tests/checkers/linter_suppress_test.go
index 9e1aa6ba5..0a0a8a6ad 100644
--- a/src/tests/checkers/linter_suppress_test.go
+++ b/src/tests/checkers/linter_suppress_test.go
@@ -9,6 +9,7 @@ import (
 func TestLinterSuppressDeprecationCall(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @deprecated some
  */
@@ -36,6 +37,7 @@ echo f(10);
 func TestLinterSuppressAll(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function g($b) {
   /** @noverify-suppress all */
   $a = $b && $b;
@@ -47,6 +49,7 @@ function g($b) {
 func TestLinterSuppressUndefinedClass(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /** @noverify-suppress undefinedClass */
 echo new Foo;
 `)
@@ -56,6 +59,7 @@ echo new Foo;
 func TestLinterSuppressNotAll(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function g($b) {
   /** @noverify-suppress dupSubExpr */
   $a = $b && $b;
@@ -70,6 +74,7 @@ function g($b) {
 func TestLinterSuppressDeadCode(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($b) {
   return $b;
 
@@ -92,6 +97,7 @@ function f($b) {
 func TestLinterSuppressWarningInGlobalScope(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $a = 100;
 
 /**
@@ -105,6 +111,7 @@ echo $a && $a;
 func TestLinterSuppressWarnings(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   private string $a = "hello";
   /** */
diff --git a/src/tests/checkers/literal_type_test.go b/src/tests/checkers/literal_type_test.go
index 7d9d0e5c2..429f3a6f8 100644
--- a/src/tests/checkers/literal_type_test.go
+++ b/src/tests/checkers/literal_type_test.go
@@ -9,6 +9,7 @@ import (
 func TestLiteralAsType(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @param '!'|'?'|'$' $a
  */
diff --git a/src/tests/checkers/misspell_test.go b/src/tests/checkers/misspell_test.go
index 34c36ef11..d0d358c9b 100644
--- a/src/tests/checkers/misspell_test.go
+++ b/src/tests/checkers/misspell_test.go
@@ -13,6 +13,7 @@ func TestMisspellPHPDocPositive(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().TypoFixer = misspell.New()
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * This function is a pure perfektion.
  */
@@ -53,6 +54,7 @@ func TestMisspellPHPDocNegative(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().TypoFixer = misspell.New()
 	test.AddFile(`<?php
+declare(strict_types = 1);
 interface Responsable {}
 
 /**
@@ -88,6 +90,7 @@ func TestMisspellNamePositive(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().TypoFixer = misspell.New()
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function unconditionnally_rollback() {}
 
 function f($notificaton) {
@@ -123,6 +126,7 @@ func TestMisspellNameNegative(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().TypoFixer = misspell.New()
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function includ() {
 }
 
diff --git a/src/tests/checkers/oop_test.go b/src/tests/checkers/oop_test.go
index 7e6a49888..99bc153ec 100644
--- a/src/tests/checkers/oop_test.go
+++ b/src/tests/checkers/oop_test.go
@@ -9,6 +9,7 @@ import (
 func TestParentConstructorCall(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Leaf {
   public function __construct() {}
 }
@@ -32,6 +33,7 @@ class WithAbstract {
 }
 `)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Good1 extends Foo {
   public function __construct() {
     parent::__construct();
@@ -52,6 +54,7 @@ class Good3 extends WithAbstract {
 }
 `)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Bad1 extends Foo {
   public function __construct() {
     echo 123;
@@ -76,6 +79,7 @@ class Bad2 extends WithTwoParams {
 
 func TestParentConstructorCallWithOtherStaticCall(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {
 	public function __construct(int $a) {}
 }
@@ -104,6 +108,7 @@ class Goo extends Foo {
 func TestNewAbstract(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 abstract class AC {
   private static function foo() {
     return new self(); // Same as AC
@@ -127,6 +132,7 @@ $x = new AC();
 func TestNewInterface(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 interface IElement {}
 $x = new IElement;
 `)
@@ -139,6 +145,7 @@ $x = new IElement;
 func TestNewTrait(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 trait Element {}
 $x = new Element;
 `)
@@ -151,6 +158,7 @@ $x = new Element;
 func TestOldStyleConstructor(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class T1 {
   /** simple constructor */
   public function T1() {}
@@ -217,6 +225,7 @@ namespace SameWithNamespace {
 func TestConstructorArgCount(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 use A\B;
 
 class OneArg {
@@ -233,6 +242,7 @@ function f() {
 }
 `)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace A\B;
 
 class TwoArgs {
@@ -251,6 +261,7 @@ class TwoArgs {
 func TestPHPDocProperty(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @property int $int
  * @property string $string - optional description.
@@ -297,6 +308,7 @@ $_ = WithProps::$int;
 func TestPHPDocPropertyForClassWithModifiers(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @property int $int
  * @property string $string - optional description.
@@ -355,6 +367,7 @@ $_ = WithProps::$int1;
 func TestInheritDoc(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 interface TestInterface {
   /**
    * @return self
@@ -377,6 +390,7 @@ interface TestInterface {
 }
 `)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo implements TestInterface {
   /** @inheritdoc */
   public function getThis() { return $this; }
@@ -399,6 +413,7 @@ $foo->acceptThis($foo);
 
 func TestMagicGetChaining(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Magic {
   /** @return Magic */
   public function __get($key) {
@@ -419,6 +434,7 @@ $m->foo->bar->method();
 func TestNonPublicMagicMethods(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class A {
   public static function __set($name, $value) {} // The magic method __set() cannot be static
   protected function __toString() {} // The magic method __call() must have public visibility
@@ -444,6 +460,7 @@ class A {
 
 func TestNonPublicMagicMethodsGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class A {
   public function __call($name, $arguments) {} // Ok
   public function __toString() {} // Ok
@@ -491,6 +508,7 @@ class A {
 func TestWrongNumberOfArgumentsInMagicMethods(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   public function __destruct($a) {} // 0
   public function __call($a) {} // 2
@@ -517,6 +535,7 @@ class Foo {
 
 func TestWrongNumberOfArgumentsInMagicMethodsGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {
   public function __construct($a) {}
   public function __construct($a, $b) {}
@@ -543,6 +562,7 @@ class Foo {
 
 func TestIteratorForeach(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 interface Iterator extends Traversable {
   public function current();
   public function key();
@@ -578,6 +598,7 @@ function testForeach($xml_str) {
 
 func TestSimpleXMLElementForeach(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 interface Traversable {}
 
 interface ArrayAccess {
@@ -616,6 +637,7 @@ function testForeach($xml_str) {
 
 func TestSimpleXMLElement(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class SimpleXMLElement {
   /** @return SimpleXMLElement */
   public function __get($name) {}
@@ -661,6 +683,7 @@ func TestLateStaticBindingForeach(t *testing.T) {
 	// as undefined. NoVerify manages to resolve it properly.
 
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class A
 {
     /**
@@ -701,6 +724,7 @@ foreach ($b->create() as $item) {
 
 func TestDerivedLateStaticBinding(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Base {
   /** @return static[] */
   public function asArray() { return []; }
@@ -723,6 +747,7 @@ $_ = $xs[0]->onlyInDerived();
 func TestStaticResolutionInsideSameClass(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	class NotA {
 		/** @return static */
 		public static function instance() {
@@ -766,6 +791,7 @@ func TestStaticResolutionInsideSameClass(t *testing.T) {
 
 func TestStaticResolutionInsideOtherStaticResolution(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	class SomeMainClass extends ParentClass {
 		/**
 		* @var string
@@ -812,6 +838,7 @@ func TestStaticResolutionInsideOtherStaticResolution(t *testing.T) {
 func TestInheritanceLoop(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	class A extends B { }
 	class B extends A { }
 
@@ -974,6 +1001,7 @@ func TestTraversable(t *testing.T) {
 func TestInstanceOfElseif2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function fn3($f3) {
   if ($f3 instanceof File) {
     return $f3->name();
@@ -1002,6 +1030,7 @@ function fn4($f4) {
 
 func TestInstanceOfElseif1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class File {
   /** @return string */
   public function filename() { return ""; }
@@ -1088,6 +1117,7 @@ func TestInstanceOf(t *testing.T) {
 func TestNullableTypes(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class A {
 	/** @var ?B */
 	public $b;
@@ -1117,6 +1147,7 @@ function test3(?A $instance) {
 
 func TestAbstractClassMethodCall(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 interface FooInterface {
   public function foo();
 }
@@ -1428,6 +1459,7 @@ interface WithoutAnyModifier {
 func TestMixinAnnotation(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace QQ\WW;
 
 /**
@@ -1454,6 +1486,7 @@ class SomeQQClass {
 `)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 use QQ\WW\SomeQQClass;
 use QQ\WW\SomeQQClass1 as SomeQQClass2;
 
@@ -1536,6 +1569,7 @@ class Bar {
 func TestGroupUse(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace Test;
 
 class TestClass {}
@@ -1546,6 +1580,7 @@ function testFunction2() {}
 `)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace Test\Something;
 
 class TestSomethingClass {}
@@ -1556,6 +1591,7 @@ function testSomethingFunction2() {}
 `)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace Foo;
 
 use Test\{
@@ -1593,6 +1629,7 @@ function f() {
 func TestTypeHintClassCaseFunctionParam(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 
 class Boo {
@@ -1663,6 +1700,7 @@ class Foo3 {
 
 func TestClassComponentsOrderGood(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Foo {
   const A = 10;
   public string $a = "";
@@ -1709,6 +1747,7 @@ class Foo5 {
 func TestCallStaticWithVariable(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /** */
   public static function some_method() {}
diff --git a/src/tests/checkers/paramClobber_test.go b/src/tests/checkers/paramClobber_test.go
index d7ee55f3a..aef982fc4 100644
--- a/src/tests/checkers/paramClobber_test.go
+++ b/src/tests/checkers/paramClobber_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestParamClobberLegacyVariadic(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f($x, $y) {
   $args = func_get_args();
   $x = $args[0];
@@ -19,6 +20,7 @@ function f($x, $y) {
 
 func TestParamClobberReferenced(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 /**
  * @param mixed[] $x
  */
@@ -31,6 +33,7 @@ function f(array $x) {
 
 func TestParamClobberConditional(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f1($x, $y) {
   if ($y) {
     $x = 10;
@@ -52,6 +55,7 @@ function f2($x) {
 func TestParamClobberFunc(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($x) {
   $x = 1343;
   return $x;
@@ -66,6 +70,7 @@ function f($x) {
 func TestParamClobberMethod(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class C {
   /** f is an example method */
   public function f($x) {
@@ -83,6 +88,7 @@ class C {
 func TestParamClobberClosure(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f() {
   return function ($x) {
     $x = 1343;
diff --git a/src/tests/checkers/phpdoc_test.go b/src/tests/checkers/phpdoc_test.go
index f46ef7ce7..7a10b3870 100644
--- a/src/tests/checkers/phpdoc_test.go
+++ b/src/tests/checkers/phpdoc_test.go
@@ -187,6 +187,7 @@ function f() {}
 func TestBadParamName(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class B1 {}
 class B2 {}
 
@@ -212,6 +213,7 @@ class Bear {
 func TestDeprecatedMethod(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /**
    * @deprecated use newMethod instead
@@ -239,6 +241,7 @@ function f() {
 func TestDeprecatedStaticMethod(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /**
    * @deprecated use newMethod instead
@@ -266,6 +269,7 @@ function f() {
 func TestDeprecatedFunction(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @deprecated use new_function instead
  */
@@ -297,6 +301,7 @@ func TestBadPHPDocTypes(t *testing.T) {
 
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @param $a
  * @param $b
@@ -319,6 +324,7 @@ function fav_func($a, $b) {
 func TestPHPDocPresence(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 	trait TheTrait {
 		public function traitPub() {}
 	}
@@ -348,6 +354,7 @@ func TestPHPDocPresence(t *testing.T) {
 func TestPHPDocSyntax(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	/**
 	 * @param $x int the x param
 	 * @param - $y the y param
@@ -374,6 +381,7 @@ func TestPHPDocSyntax(t *testing.T) {
 func TestPHPDocVar(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /** @var integer $x */
   public $x;
@@ -396,6 +404,7 @@ class Foo {
 func TestPHPDocProperty2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @property integer $int
  * @property []t ts
@@ -423,6 +432,7 @@ class Foo {}
 func TestPHPDocType(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	/**
 	 * @param [][]string $x1
 	 * @param double $x2
@@ -452,6 +462,7 @@ func TestPHPDocType(t *testing.T) {
 func TestPHPDocIncorrectSyntaxOptionalTypesType(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	class Foo {}
 
 	/**
@@ -476,6 +487,7 @@ func TestPHPDocIncorrectSyntaxOptionalTypesType(t *testing.T) {
 func TestPHPDocInvalidBeginning(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   /*
    * @var int
@@ -529,6 +541,7 @@ function f2($a) {
 func TestPHPDocTwiceNullableTypes(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 
 /**
diff --git a/src/tests/checkers/printf_test.go b/src/tests/checkers/printf_test.go
index e19e70b4a..4f08c6fbb 100644
--- a/src/tests/checkers/printf_test.go
+++ b/src/tests/checkers/printf_test.go
@@ -10,6 +10,7 @@ func TestSprintf(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/standard/standard_2.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @param mixed[] $a
  */
@@ -45,6 +46,7 @@ func TestPrintf(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/standard/standard_2.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 /**
  * @param mixed[] $a
  */
diff --git a/src/tests/checkers/regexpsimplify_test.go b/src/tests/checkers/regexpsimplify_test.go
index c501a0d4e..87d973000 100644
--- a/src/tests/checkers/regexpsimplify_test.go
+++ b/src/tests/checkers/regexpsimplify_test.go
@@ -10,6 +10,7 @@ func TestRESimplifyNamedCaptureForms(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($s) {
   preg_match('~(?P<abc>[0-9])~', $s);
   preg_match('~(?<abc>[0-9])~', $s);
@@ -27,6 +28,7 @@ func TestRESimplifyMixed(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($s) {
   preg_match('/x(?:a|b|c){0,}/', $s);
   preg_match_all('/^write([-]?\d\d*)?$/i', $s);
@@ -47,6 +49,7 @@ func TestRESimplify(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 // (?:x) -> x
 function ungroup($s) {
   preg_match('/(?:x)/', $s);
@@ -146,6 +149,7 @@ func TestRESimplifyChangeDelim(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($s) {
   preg_match('/^http:\/\//', $s);
   preg_match('/^http:\/\/~/', $s);
@@ -166,6 +170,7 @@ func TestRENegativeTests(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($s) {
   // Should not suggest unescaping the delimiter.
   preg_match('/\//', $s);
diff --git a/src/tests/checkers/regexpvet_test.go b/src/tests/checkers/regexpvet_test.go
index c97770d64..1f5f98ebe 100644
--- a/src/tests/checkers/regexpvet_test.go
+++ b/src/tests/checkers/regexpvet_test.go
@@ -13,6 +13,7 @@ func TestREVetParse(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function parseErrors($s) {
   preg_match('', $s);
   preg_match('aba', $s);
@@ -194,6 +195,7 @@ func TestREVet_2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($s) {
   preg_match('/(?m)^([\s\t]*)([\*\-\+]|\d\.)\s+/', $s);
   preg_match('~^(www.|https://|http://)*[A-Za-z0-9._%+\-]+\.[com|org|edu|net]{3}$~', $s);
@@ -242,6 +244,7 @@ func TestREVet_4(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/pcre/pcre.php`}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function goodFlags($s) {
 	preg_match('~(?:(?i)foo)(?i)bar~', $s);
 	preg_match('~(?m)(?i)(?-m)(?-i)(?m)(?i)~', $s);
diff --git a/src/tests/checkers/relative_name_test.go b/src/tests/checkers/relative_name_test.go
index fa90e2ac3..bf6276e11 100644
--- a/src/tests/checkers/relative_name_test.go
+++ b/src/tests/checkers/relative_name_test.go
@@ -9,6 +9,7 @@ import (
 func TestRelativeName1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace A;
 
 class ClassA {}
@@ -18,6 +19,7 @@ $_ = new namespace\ClassA();
 `)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 namespace A\B;
 
 class ClassB {}
@@ -26,6 +28,7 @@ $_ = new namespace\ClassB();
 `)
 
 	test.AddFile(`<?php
+declare(strict_types = 1);
 $_ = new namespace\A\B\ClassB();
 `)
 
diff --git a/src/tests/checkers/shape_test.go b/src/tests/checkers/shape_test.go
index c2d66e684..87674e531 100644
--- a/src/tests/checkers/shape_test.go
+++ b/src/tests/checkers/shape_test.go
@@ -12,6 +12,7 @@ func TestShapePropertyFetch(t *testing.T) {
 
 	test := linttest.NewSuite(t)
 	test.AddNamedFile("a/b/test.php", `<?php
+declare(strict_types = 1);
 /**
  * @param \shape(x:int,y:float) $s
  */
@@ -31,6 +32,7 @@ func TestShapeDimFetch(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {
   public $x = 10;
   public $y = 1.5;
@@ -55,6 +57,7 @@ func TestShapeIntKey(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Box { public $value; }
 
 function f() {
@@ -78,6 +81,7 @@ func TestShapeSyntax(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Box { public $value; }
 
 class T {
@@ -135,6 +139,7 @@ echo $t->good6['y']->value;
 
 func TestShapeReturn(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class MyList {
   /** @var \MyList */
   public $next;
@@ -150,6 +155,7 @@ echo $s1['list']->next->next;
 
 func TestTuple(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class Box { public $value; }
 
 class T {
diff --git a/src/tests/checkers/strict_mixed_test.go b/src/tests/checkers/strict_mixed_test.go
index 7c4f094e6..038baabbc 100644
--- a/src/tests/checkers/strict_mixed_test.go
+++ b/src/tests/checkers/strict_mixed_test.go
@@ -10,6 +10,7 @@ func TestStrictMixedEnabled(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 
 function f($a) {
@@ -79,6 +80,7 @@ function f(stdClass|null $a) {
 func TestStrictMixedDisabled(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 class Foo {}
 
 function f($a) {
diff --git a/src/tests/checkers/stripTags_test.go b/src/tests/checkers/stripTags_test.go
index 3ad6a781f..0985532e6 100644
--- a/src/tests/checkers/stripTags_test.go
+++ b/src/tests/checkers/stripTags_test.go
@@ -10,6 +10,7 @@ func TestStripTagsGood(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{"stubs/phpstorm-stubs/standard/standard_1.php"}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f(string $s) {
   $_ = strip_tags($s, ['br', 'a']);
   $_ = strip_tags($s, ['BR']);
@@ -25,6 +26,7 @@ func TestStripTagsArray(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{"stubs/phpstorm-stubs/standard/standard_1.php"}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f(string $s) {
   return strip_tags($s, ['<br>', 'a', 'A']);
 }
@@ -40,6 +42,7 @@ func TestStripTagsString1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{"stubs/phpstorm-stubs/standard/standard_1.php"}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f1(string $s) {
   return strip_tags($s, '<a href="#">');
 }
@@ -58,6 +61,7 @@ func TestStripTagsString2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{"stubs/phpstorm-stubs/standard/standard_1.php"}
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f(string $s) {
   return strip_tags($s, '<a ><br/><br>');
 }
diff --git a/src/tests/checkers/trait_test.go b/src/tests/checkers/trait_test.go
index 884e37274..167d820bf 100644
--- a/src/tests/checkers/trait_test.go
+++ b/src/tests/checkers/trait_test.go
@@ -9,6 +9,7 @@ import (
 func TestTraitSingleton(t *testing.T) {
 	// See #533.
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 trait Singleton {
   /**
    * @var ?self
diff --git a/src/tests/checkers/trigger_error_test.go b/src/tests/checkers/trigger_error_test.go
index a5d909af2..a1ee8e8ac 100644
--- a/src/tests/checkers/trigger_error_test.go
+++ b/src/tests/checkers/trigger_error_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestTriggerNonError(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 trigger_error('notice');
 trigger_error('also notice', E_USER_NOTICE);
 trigger_error('a warning', E_USER_WARNING);
@@ -17,6 +18,7 @@ trigger_error('a warning', E_USER_WARNING);
 func TestTriggerErrorFQN(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 \trigger_error('error', E_USER_ERROR);
 echo 'unreachable';
 `)
@@ -29,6 +31,7 @@ echo 'unreachable';
 func TestTriggerError(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 trigger_error('error', E_USER_ERROR);
 echo 'unreachable';
 `)
@@ -41,6 +44,7 @@ echo 'unreachable';
 func TestTriggerErrorTransitive(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function f($msg) {
   trigger_error($msg, E_USER_ERROR);
 }
@@ -58,6 +62,7 @@ func TestUserError(t *testing.T) {
 	// user_error is a trigger_error alias.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 user_error('error', E_USER_ERROR);
 echo 'unreachable';
 `)
diff --git a/src/tests/checkers/typehint_test.go b/src/tests/checkers/typehint_test.go
index db14990a3..15ef61a1a 100644
--- a/src/tests/checkers/typehint_test.go
+++ b/src/tests/checkers/typehint_test.go
@@ -9,6 +9,7 @@ import (
 func TestTypeHintGood(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 abstract class FooAbstract {
     /**
      * @return string[]
diff --git a/src/tests/golden/golden_test.go b/src/tests/golden/golden_test.go
index be5002069..4c83bc945 100644
--- a/src/tests/golden/golden_test.go
+++ b/src/tests/golden/golden_test.go
@@ -39,6 +39,8 @@ func TestGolden(t *testing.T) {
 			Name: "embeddedrules",
 			Disable: []string{
 				"deadCode",
+				"notStrictTypes",
+				"noDeclareSection",
 			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
@@ -50,6 +52,8 @@ func TestGolden(t *testing.T) {
 			Disable: []string{
 				"arraySyntax",
 				"redundantCast",
+				"notStrictTypes",
+				"noDeclareSection",
 			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
@@ -62,6 +66,10 @@ func TestGolden(t *testing.T) {
 
 		{
 			Name: "math",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/gmp/gmp.php`,
@@ -73,6 +81,10 @@ func TestGolden(t *testing.T) {
 
 		{
 			Name: "qrcode",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/gd/gd.php`,
@@ -81,6 +93,10 @@ func TestGolden(t *testing.T) {
 
 		{
 			Name: "ctype",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 			},
@@ -88,14 +104,22 @@ func TestGolden(t *testing.T) {
 
 		{
 			Name: "idn",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/mbstring/mbstring.php`,
 			},
 		},
 
 		{
-			Name:    "parsedown",
-			Disable: []string{"missingPhpdoc", "arraySyntax"},
+			Name: "parsedown",
+			Disable: []string{"missingPhpdoc",
+				"arraySyntax",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/mbstring/mbstring.php`,
@@ -103,16 +127,24 @@ func TestGolden(t *testing.T) {
 		},
 
 		{
-			Name:    "underscore",
-			Disable: []string{"missingPhpdoc"},
+			Name: "underscore",
+			Disable: []string{
+				"missingPhpdoc",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 			},
 		},
 
 		{
-			Name:    "phprocksyd",
-			Disable: []string{"missingPhpdoc"},
+			Name: "phprocksyd",
+			Disable: []string{
+				"missingPhpdoc",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/standard/basic.php`,
 				`stubs/phpstorm-stubs/pcntl/pcntl.php`,
@@ -122,8 +154,12 @@ func TestGolden(t *testing.T) {
 		},
 
 		{
-			Name:    "flysystem",
-			Disable: []string{"redundantCast"},
+			Name: "flysystem",
+			Disable: []string{
+				"redundantCast",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/SPL/SPL.php`,
@@ -139,8 +175,12 @@ func TestGolden(t *testing.T) {
 		},
 
 		{
-			Name:    "inflector",
-			Disable: []string{"missingPhpdoc"},
+			Name: "inflector",
+			Disable: []string{
+				"missingPhpdoc",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/SPL/SPL.php`,
@@ -149,8 +189,12 @@ func TestGolden(t *testing.T) {
 		},
 
 		{
-			Name:    "options-resolver",
-			Disable: []string{"missingPhpdoc"},
+			Name: "options-resolver",
+			Disable: []string{
+				"missingPhpdoc",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/SPL/SPL.php`,
 				`stubs/phpstorm-stubs/Reflection/Reflection.php`,
@@ -162,8 +206,13 @@ func TestGolden(t *testing.T) {
 		},
 
 		{
-			Name:    "twitter-api-php",
-			Disable: []string{"missingPhpdoc", "arraySyntax"},
+			Name: "twitter-api-php",
+			Disable: []string{
+				"missingPhpdoc",
+				"arraySyntax",
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			Deps: []string{
 				`stubs/phpstorm-stubs/pcre/pcre.php`,
 				`stubs/phpstorm-stubs/SPL/SPL.php`,
@@ -176,22 +225,38 @@ func TestGolden(t *testing.T) {
 
 		{
 			Name: "output-test",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 		},
 
 		{
-			Name:      "gitignore-test",
+			Name: "gitignore-test",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			OnlyE2E:   true,
 			Gitignore: true,
 		},
 
 		{
-			Name:     "baseline-test",
+			Name: "baseline-test",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 			OnlyE2E:  true,
 			Baseline: true,
 		},
 
 		{
 			Name: "phpdoc",
+			Disable: []string{
+				"notStrictTypes",
+				"noDeclareSection",
+			},
 		},
 	}
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/CachedWordInflector.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/CachedWordInflector.php
index b59ac46c1..c15916c74 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/CachedWordInflector.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/CachedWordInflector.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Inflector.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Inflector.php
index 241191850..487c8d594 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Inflector.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Inflector.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/InflectorFactory.php
index 2becad618..12eb2485d 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Language.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Language.php
index 78c3cc756..9b072b33d 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Language.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Language.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/NoopWordInflector.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/NoopWordInflector.php
index 63806ecce..7b1e74ac7 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/NoopWordInflector.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/NoopWordInflector.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Inflectible.php
index ce86dbe05..c2734a19c 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\English;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/InflectorFactory.php
index 2a67d219e..bced62013 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\English;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Rules.php
index fcc1d19cf..8876c97c8 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\English;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Uninflected.php
index 14a942665..c77d35026 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/English/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\English;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Inflectible.php
index b3f22ed28..57fb30330 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\French;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/InflectorFactory.php
index dc9cc7ea1..889d0e7d7 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\French;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Rules.php
index d25f8a8c4..1e868894d 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\French;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Uninflected.php
index 2fdc020a4..5af549b52 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/French/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\French;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Inflectible.php
index 9fae0f36e..e52e93c88 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\NorwegianBokmal;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/InflectorFactory.php
index 8609ac411..2aef9d25c 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\NorwegianBokmal;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Rules.php
index 5a92132a3..b03ff7d3d 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\NorwegianBokmal;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Uninflected.php
index c6b9fc792..403de171a 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/NorwegianBokmal/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\NorwegianBokmal;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Pattern.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Pattern.php
index 3486eba57..21c0005b3 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Pattern.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Pattern.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Patterns.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Patterns.php
index a71f1ed20..c1cceff5a 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Patterns.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Patterns.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Inflectible.php
index 155055f7a..834bdb3fe 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Portuguese;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/InflectorFactory.php
index 4e99e23e8..fbda0ca40 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Portuguese;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Rules.php
index de69b7ecd..699b4ea61 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Portuguese;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Uninflected.php
index 52360c456..bf5a1ebff 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Portuguese/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Portuguese;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Ruleset.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Ruleset.php
index a2d32c1da..d05a336e4 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Ruleset.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Ruleset.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Inflectible.php
index 6cace86a9..babfe839a 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Spanish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/InflectorFactory.php
index 0ee46e33b..a41a9b232 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Spanish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Rules.php
index f77a739bb..c10d7d8ae 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Spanish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Uninflected.php
index b13281e8d..4f1b04b65 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Spanish/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Spanish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitution.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitution.php
index 681ab6319..3bf780d15 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitution.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitution.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitutions.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitutions.php
index 24cc34a8e..723bd2d94 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitutions.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Substitutions.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformation.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformation.php
index 84ef08b8d..79355342f 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformation.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformation.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformations.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformations.php
index 9f4724e50..421c98b9a 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformations.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Transformations.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Inflectible.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Inflectible.php
index 74900cb99..d5fd64264 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Inflectible.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Inflectible.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Turkish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/InflectorFactory.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/InflectorFactory.php
index 1bcb984ee..68589a9fe 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/InflectorFactory.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/InflectorFactory.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Turkish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Rules.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Rules.php
index dd0840c5a..abc708538 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Rules.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Rules.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Turkish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Uninflected.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Uninflected.php
index c95ccbf9b..c1214bade 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Uninflected.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Turkish/Uninflected.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules\Turkish;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Word.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Word.php
index 5156e934b..8bd64c3a2 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Word.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/Rules/Word.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector\Rules;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/RulesetInflector.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/RulesetInflector.php
index 9db69e85a..d4a90a356 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/RulesetInflector.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/RulesetInflector.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/WordInflector.php b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/WordInflector.php
index f25705580..efca5409a 100644
--- a/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/WordInflector.php
+++ b/src/tests/golden/testdata/inflector/lib/Doctrine/Inflector/WordInflector.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Doctrine\Inflector;
 
diff --git a/src/tests/golden/testdata/math/src/BigDecimal.php b/src/tests/golden/testdata/math/src/BigDecimal.php
index 29bdd320b..c4ef4e0d7 100644
--- a/src/tests/golden/testdata/math/src/BigDecimal.php
+++ b/src/tests/golden/testdata/math/src/BigDecimal.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math;
 
diff --git a/src/tests/golden/testdata/math/src/BigInteger.php b/src/tests/golden/testdata/math/src/BigInteger.php
index c811d17bd..4bfdb6f34 100644
--- a/src/tests/golden/testdata/math/src/BigInteger.php
+++ b/src/tests/golden/testdata/math/src/BigInteger.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math;
 
diff --git a/src/tests/golden/testdata/math/src/BigNumber.php b/src/tests/golden/testdata/math/src/BigNumber.php
index acd6b3d50..2f2a00b6a 100644
--- a/src/tests/golden/testdata/math/src/BigNumber.php
+++ b/src/tests/golden/testdata/math/src/BigNumber.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math;
 
diff --git a/src/tests/golden/testdata/math/src/BigRational.php b/src/tests/golden/testdata/math/src/BigRational.php
index ff035c5c0..3e6e6cb1c 100644
--- a/src/tests/golden/testdata/math/src/BigRational.php
+++ b/src/tests/golden/testdata/math/src/BigRational.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/DivisionByZeroException.php b/src/tests/golden/testdata/math/src/Exception/DivisionByZeroException.php
index 49a9157f1..56a92a0c7 100644
--- a/src/tests/golden/testdata/math/src/Exception/DivisionByZeroException.php
+++ b/src/tests/golden/testdata/math/src/Exception/DivisionByZeroException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/IntegerOverflowException.php b/src/tests/golden/testdata/math/src/Exception/IntegerOverflowException.php
index e0b07d3c7..55ffc55d4 100644
--- a/src/tests/golden/testdata/math/src/Exception/IntegerOverflowException.php
+++ b/src/tests/golden/testdata/math/src/Exception/IntegerOverflowException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/MathException.php b/src/tests/golden/testdata/math/src/Exception/MathException.php
index 3fc37a0d7..916479bab 100644
--- a/src/tests/golden/testdata/math/src/Exception/MathException.php
+++ b/src/tests/golden/testdata/math/src/Exception/MathException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/NegativeNumberException.php b/src/tests/golden/testdata/math/src/Exception/NegativeNumberException.php
index 473911341..d9f155036 100644
--- a/src/tests/golden/testdata/math/src/Exception/NegativeNumberException.php
+++ b/src/tests/golden/testdata/math/src/Exception/NegativeNumberException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/NumberFormatException.php b/src/tests/golden/testdata/math/src/Exception/NumberFormatException.php
index 2fd0be73a..f7e02a26e 100644
--- a/src/tests/golden/testdata/math/src/Exception/NumberFormatException.php
+++ b/src/tests/golden/testdata/math/src/Exception/NumberFormatException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Exception/RoundingNecessaryException.php b/src/tests/golden/testdata/math/src/Exception/RoundingNecessaryException.php
index 1c6100563..b3dac1267 100644
--- a/src/tests/golden/testdata/math/src/Exception/RoundingNecessaryException.php
+++ b/src/tests/golden/testdata/math/src/Exception/RoundingNecessaryException.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Exception;
 
diff --git a/src/tests/golden/testdata/math/src/Internal/Calculator.php b/src/tests/golden/testdata/math/src/Internal/Calculator.php
index 3e59a2961..bf729a966 100644
--- a/src/tests/golden/testdata/math/src/Internal/Calculator.php
+++ b/src/tests/golden/testdata/math/src/Internal/Calculator.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Internal;
 
diff --git a/src/tests/golden/testdata/math/src/Internal/Calculator/BcMathCalculator.php b/src/tests/golden/testdata/math/src/Internal/Calculator/BcMathCalculator.php
index 944ee9edb..a8a9321f7 100644
--- a/src/tests/golden/testdata/math/src/Internal/Calculator/BcMathCalculator.php
+++ b/src/tests/golden/testdata/math/src/Internal/Calculator/BcMathCalculator.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Internal\Calculator;
 
diff --git a/src/tests/golden/testdata/math/src/Internal/Calculator/GmpCalculator.php b/src/tests/golden/testdata/math/src/Internal/Calculator/GmpCalculator.php
index 01926da87..1dde7015d 100644
--- a/src/tests/golden/testdata/math/src/Internal/Calculator/GmpCalculator.php
+++ b/src/tests/golden/testdata/math/src/Internal/Calculator/GmpCalculator.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Internal\Calculator;
 
diff --git a/src/tests/golden/testdata/math/src/Internal/Calculator/NativeCalculator.php b/src/tests/golden/testdata/math/src/Internal/Calculator/NativeCalculator.php
index 8264bf8ae..303cefb55 100644
--- a/src/tests/golden/testdata/math/src/Internal/Calculator/NativeCalculator.php
+++ b/src/tests/golden/testdata/math/src/Internal/Calculator/NativeCalculator.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math\Internal\Calculator;
 
diff --git a/src/tests/golden/testdata/math/src/RoundingMode.php b/src/tests/golden/testdata/math/src/RoundingMode.php
index 06936d8db..211b25946 100644
--- a/src/tests/golden/testdata/math/src/RoundingMode.php
+++ b/src/tests/golden/testdata/math/src/RoundingMode.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace Brick\Math;
 
diff --git a/src/tests/golden/testdata/quickfix/arraySyntax.php.fix.expected b/src/tests/golden/testdata/quickfix/arraySyntax.php.fix.expected
index 4e4199df7..e49e42c08 100644
--- a/src/tests/golden/testdata/quickfix/arraySyntax.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/arraySyntax.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 class Foo {}
 
 $_ = [1,2,3];
diff --git a/src/tests/golden/testdata/quickfix/binaryOp.php.fix.expected b/src/tests/golden/testdata/quickfix/binaryOp.php.fix.expected
index 20aeea871..6bbf10192 100644
--- a/src/tests/golden/testdata/quickfix/binaryOp.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/binaryOp.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function binaryOp() {
     $x += $y;
     $x -= $y;
diff --git a/src/tests/golden/testdata/quickfix/callSimplify.php.fix.expected b/src/tests/golden/testdata/quickfix/callSimplify.php.fix.expected
index 0c4c16216..dc1fd0ba6 100644
--- a/src/tests/golden/testdata/quickfix/callSimplify.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/callSimplify.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 $array = ['a' => 1, 'b' => 2, 'c' => 3];
 
 if (array_key_exists('z', $array)) { // 2
diff --git a/src/tests/golden/testdata/quickfix/complexExamples.php.fix.expected b/src/tests/golden/testdata/quickfix/complexExamples.php.fix.expected
index 503b05611..3ed4c9e56 100644
--- a/src/tests/golden/testdata/quickfix/complexExamples.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/complexExamples.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function foo(array $a) { return 0; }
 
 $_ = [isset($x) ? $x : $y]; // expressions in global scope
diff --git a/src/tests/golden/testdata/quickfix/constCase.php.fix.expected b/src/tests/golden/testdata/quickfix/constCase.php.fix.expected
index ddb269565..3d8fbc1a2 100644
--- a/src/tests/golden/testdata/quickfix/constCase.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/constCase.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function f($a) {
     if ($a === null) {
         return false;
diff --git a/src/tests/golden/testdata/quickfix/declareStrictTypes.php b/src/tests/golden/testdata/quickfix/declareStrictTypes.php
new file mode 100644
index 000000000..72d4c306e
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/declareStrictTypes.php
@@ -0,0 +1,6 @@
+<?php
+declare(strict_types = 0);
+
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/declareStrictTypes.php.fix.expected b/src/tests/golden/testdata/quickfix/declareStrictTypes.php.fix.expected
new file mode 100644
index 000000000..4a69e494b
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/declareStrictTypes.php.fix.expected
@@ -0,0 +1,6 @@
+<?php
+declare(strict_types = 1);
+
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/getTypeMisUse.php.fix.expected b/src/tests/golden/testdata/quickfix/getTypeMisUse.php.fix.expected
index e100ed695..760b683f2 100644
--- a/src/tests/golden/testdata/quickfix/getTypeMisUse.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/getTypeMisUse.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function getTypeMisUse(mixed $var) {
   if (is_string($var)) {
   }
diff --git a/src/tests/golden/testdata/quickfix/indexingSyntax.php.fix.expected b/src/tests/golden/testdata/quickfix/indexingSyntax.php.fix.expected
index fc718ad84..d0f0912ee 100644
--- a/src/tests/golden/testdata/quickfix/indexingSyntax.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/indexingSyntax.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 $b = [];
 $_ = $b[0];
 $_ = $b[0][0];
diff --git a/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php
new file mode 100644
index 000000000..6f91722ee
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php
@@ -0,0 +1,4 @@
+<?php
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php.fix.expected b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php.fix.expected
new file mode 100644
index 000000000..d96dd7b2c
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_1.php.fix.expected
@@ -0,0 +1,5 @@
+<?php
+declare(strict_types = 1);
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php
new file mode 100644
index 000000000..8c8b953e7
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php
@@ -0,0 +1,5 @@
+<?php
+declare(ticks = 1);
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php.fix.expected b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php.fix.expected
new file mode 100644
index 000000000..04213d161
--- /dev/null
+++ b/src/tests/golden/testdata/quickfix/noDeclareStrictTypesSection_2.php.fix.expected
@@ -0,0 +1,6 @@
+<?php
+declare(strict_types = 1);
+declare(ticks = 1);
+function test():string {
+    return "test";
+}
diff --git a/src/tests/golden/testdata/quickfix/propNullDefault.php.fix.expected b/src/tests/golden/testdata/quickfix/propNullDefault.php.fix.expected
index cec8556c0..e6e0ccbab 100644
--- a/src/tests/golden/testdata/quickfix/propNullDefault.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/propNullDefault.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 class Boo {}
 class Zoo {}
 
diff --git a/src/tests/golden/testdata/quickfix/ternarySimplify.php.fix.expected b/src/tests/golden/testdata/quickfix/ternarySimplify.php.fix.expected
index ea918f180..cb93d02b5 100644
--- a/src/tests/golden/testdata/quickfix/ternarySimplify.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/ternarySimplify.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 $a = 5;
 function f(): int {
     global $a;
diff --git a/src/tests/golden/testdata/quickfix/trailingComma.php.fix.expected b/src/tests/golden/testdata/quickfix/trailingComma.php.fix.expected
index 4e7d7da0e..005cd5b9a 100644
--- a/src/tests/golden/testdata/quickfix/trailingComma.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/trailingComma.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function f() {
     $_ = [10, 20, 30]; // ok
 
diff --git a/src/tests/golden/testdata/quickfix/unaryRepeat.php.fix.expected b/src/tests/golden/testdata/quickfix/unaryRepeat.php.fix.expected
index 0ab71c51e..712def091 100644
--- a/src/tests/golden/testdata/quickfix/unaryRepeat.php.fix.expected
+++ b/src/tests/golden/testdata/quickfix/unaryRepeat.php.fix.expected
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types = 1);
 function unaryRepeat() {
   $a = 100;
 
diff --git a/src/tests/inline/testdata/php8/deprecated_annotation_any.php b/src/tests/inline/testdata/php8/deprecated_annotation_any.php
index c6cfa7906..ee354ea98 100644
--- a/src/tests/inline/testdata/php8/deprecated_annotation_any.php
+++ b/src/tests/inline/testdata/php8/deprecated_annotation_any.php
@@ -1,4 +1,5 @@
 <?php
+declare(strict_types = 1);
 
 use JetBrains\PhpStorm\Deprecated;
 
diff --git a/src/tests/inline/testdata/php8/param_available_any.php b/src/tests/inline/testdata/php8/param_available_any.php
index 25d9bf0e3..681e25f8a 100644
--- a/src/tests/inline/testdata/php8/param_available_any.php
+++ b/src/tests/inline/testdata/php8/param_available_any.php
@@ -1,4 +1,5 @@
 <?php
+declare(strict_types = 1);
 
 use JetBrains\PhpStorm\Internal\PhpStormStubsElementAvailable;
 
diff --git a/src/tests/inline/testdata/php8/propertyPromotion_any.php b/src/tests/inline/testdata/php8/propertyPromotion_any.php
index 0d5c45178..b715d7155 100644
--- a/src/tests/inline/testdata/php8/propertyPromotion_any.php
+++ b/src/tests/inline/testdata/php8/propertyPromotion_any.php
@@ -1,4 +1,5 @@
 <?php
+declare(strict_types = 1);
 
 class Boo {
   /***/
diff --git a/src/tests/regression/issue1071_test.go b/src/tests/regression/issue1071_test.go
index f18db4f42..65d75aa3c 100644
--- a/src/tests/regression/issue1071_test.go
+++ b/src/tests/regression/issue1071_test.go
@@ -13,6 +13,7 @@ func TestIssue1071FunctionWithBackSlash(t *testing.T) {
 		"stubs/phpstorm-stubs/meta/.phpstorm.meta.php",
 	}
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 class Foo {
   /**
    * @return int
diff --git a/src/tests/regression/issue11_test.go b/src/tests/regression/issue11_test.go
index 580ae28bd..228e2720e 100644
--- a/src/tests/regression/issue11_test.go
+++ b/src/tests/regression/issue11_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue11(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	class Generator {
 		/** send sends a message */
 		public function send();
diff --git a/src/tests/regression/issue128_test.go b/src/tests/regression/issue128_test.go
index d21a41a8c..2a251fcfd 100644
--- a/src/tests/regression/issue128_test.go
+++ b/src/tests/regression/issue128_test.go
@@ -11,6 +11,7 @@ func TestIssue128(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 class Value {
   public $x;
 }
diff --git a/src/tests/regression/issue16_test.go b/src/tests/regression/issue16_test.go
index e0c87999b..aafd2cf97 100644
--- a/src/tests/regression/issue16_test.go
+++ b/src/tests/regression/issue16_test.go
@@ -10,6 +10,7 @@ func TestIssue16(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	interface DateTimeInterface {
 		public function format($fmt);
 	}
diff --git a/src/tests/regression/issue170_test.go b/src/tests/regression/issue170_test.go
index 09d862f4e..4756ab376 100644
--- a/src/tests/regression/issue170_test.go
+++ b/src/tests/regression/issue170_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue170(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 
 global $v;
 
diff --git a/src/tests/regression/issue182_test.go b/src/tests/regression/issue182_test.go
index 8d36c12f9..ba49b6cbd 100644
--- a/src/tests/regression/issue182_test.go
+++ b/src/tests/regression/issue182_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue182(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 trait SingletonSelf {
     /** @var ?self */
     private static $instance = null;
diff --git a/src/tests/regression/issue183_test.go b/src/tests/regression/issue183_test.go
index 4695f4c9c..6c9582c80 100644
--- a/src/tests/regression/issue183_test.go
+++ b/src/tests/regression/issue183_test.go
@@ -9,6 +9,7 @@ import (
 func TestIssue183(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
     trait Mixin {
         public $x = 10;
     }
diff --git a/src/tests/regression/issue1_test.go b/src/tests/regression/issue1_test.go
index cffefaa45..bce604c01 100644
--- a/src/tests/regression/issue1_test.go
+++ b/src/tests/regression/issue1_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	interface TestInterface
 	{
 		const TEST = '1';
diff --git a/src/tests/regression/issue209_test.go b/src/tests/regression/issue209_test.go
index a89fa4893..c7a9587db 100644
--- a/src/tests/regression/issue209_test.go
+++ b/src/tests/regression/issue209_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue209_1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 trait A {
   private function priv() { return 1; }
   protected function prot() { return 2; }
@@ -30,6 +31,7 @@ echo (new B)->sum(); // actual PHP prints 6
 func TestIssue209_2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 trait Methods {
   /***/
   public function pubMethod() {}
diff --git a/src/tests/regression/issue252_test.go b/src/tests/regression/issue252_test.go
index a2d920b19..5746e37f2 100644
--- a/src/tests/regression/issue252_test.go
+++ b/src/tests/regression/issue252_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue252(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 class Foo {
   public $foo = 10;
 }
@@ -30,6 +31,7 @@ function alt_if($v) {
 
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function alt_for() {
   for ($i = 0; $i < 10; $i++):
     $x1 = 10;
diff --git a/src/tests/regression/issue26_test.go b/src/tests/regression/issue26_test.go
index 6e2a99481..7b169eaf0 100644
--- a/src/tests/regression/issue26_test.go
+++ b/src/tests/regression/issue26_test.go
@@ -10,6 +10,7 @@ func TestIssue26_1(t *testing.T) {
 	// Test that defined variable variable don't cause "undefined" warnings.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function issetVarVar() {
 		$x = 'key';
 		if (isset($$x)) {
@@ -28,6 +29,7 @@ func TestIssue26_2(t *testing.T) {
 	// Test that if $x is defined, it doesn't make $$x defined.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function issetVarVar() {
 		if (isset($x)) {
 			$_ = $x;  // $x is defined
@@ -43,6 +45,7 @@ func TestIssue26_3(t *testing.T) {
 	// other variables. Also warn for undefined variable in $$x.
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function issetVarVar() {
 		if (isset($$x)) {
 			$_ = $$y;
@@ -58,6 +61,7 @@ func TestIssue26_3(t *testing.T) {
 func TestIssue26_4(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	function issetVarVar() {
 		if (isset($$$$x)) {
 			$_ = $$$$x; // Can't track this level of indirection
diff --git a/src/tests/regression/issue283_test.go b/src/tests/regression/issue283_test.go
index 84f132cef..80521936f 100644
--- a/src/tests/regression/issue283_test.go
+++ b/src/tests/regression/issue283_test.go
@@ -9,6 +9,7 @@ import (
 func TestIssue283(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 trait YummyProps {
   public $price = 'fair';
   protected $taste = 'good';
diff --git a/src/tests/regression/issue288_test.go b/src/tests/regression/issue288_test.go
index 4ce757e6c..050e77250 100644
--- a/src/tests/regression/issue288_test.go
+++ b/src/tests/regression/issue288_test.go
@@ -10,6 +10,7 @@ func TestIssue288(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 class Box {
   public $item1;
   public $item2;
diff --git a/src/tests/regression/issue289_test.go b/src/tests/regression/issue289_test.go
index 65f6c5311..82e797e27 100644
--- a/src/tests/regression/issue289_test.go
+++ b/src/tests/regression/issue289_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue289(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 class Foo { public $value = 11; }
 
 $xs = [0, new Foo()];
diff --git a/src/tests/regression/issue2_test.go b/src/tests/regression/issue2_test.go
index 3e16d9b22..cedde97d6 100644
--- a/src/tests/regression/issue2_test.go
+++ b/src/tests/regression/issue2_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	function rand() { return 4; }
 
 	interface DateTimeInterface {
diff --git a/src/tests/regression/issue327_test.go b/src/tests/regression/issue327_test.go
index 935448167..0e629a3c4 100644
--- a/src/tests/regression/issue327_test.go
+++ b/src/tests/regression/issue327_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue327(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 function sink(...$args) {}
 
 function f() {
diff --git a/src/tests/regression/issue362_test.go b/src/tests/regression/issue362_test.go
index f0930a1ed..ed7389a29 100644
--- a/src/tests/regression/issue362_test.go
+++ b/src/tests/regression/issue362_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue362_1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 function method_exists($object, $method_name) { return 1 != 0; }
 
 class Foo {
@@ -43,6 +44,7 @@ func TestIssue362_2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+declare(strict_types = 1);
 function method_exists($object, $method_name) { return 1 != 0; }
 
 class Foo {}
diff --git a/src/tests/regression/issue375_test.go b/src/tests/regression/issue375_test.go
index 1dffff357..f746caeee 100644
--- a/src/tests/regression/issue375_test.go
+++ b/src/tests/regression/issue375_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue375(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 function ref_sink(&$ref) {}
 
 function f() {
diff --git a/src/tests/regression/issue37_test.go b/src/tests/regression/issue37_test.go
index b8861837e..5417c6739 100644
--- a/src/tests/regression/issue37_test.go
+++ b/src/tests/regression/issue37_test.go
@@ -9,6 +9,7 @@ import (
 func TestIssue37(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 	class Foo {
 		public $a;
 		public $b;
diff --git a/src/tests/regression/issue387_test.go b/src/tests/regression/issue387_test.go
index 0a3a5c9cb..64c64eb34 100644
--- a/src/tests/regression/issue387_test.go
+++ b/src/tests/regression/issue387_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue387(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 function f1(&$a) {
     $a1[0] = 1;
 }
diff --git a/src/tests/regression/issue390_test.go b/src/tests/regression/issue390_test.go
index 9d06f60b5..173bd43d7 100644
--- a/src/tests/regression/issue390_test.go
+++ b/src/tests/regression/issue390_test.go
@@ -10,6 +10,7 @@ func TestIssue390(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.Config().StrictMixed = true
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 $cond = 1;
 if ($cond && isset($a1[0])) {
   $_ = $a1;
diff --git a/src/tests/regression/issue3_test.go b/src/tests/regression/issue3_test.go
index a755ccfae..81d4b0204 100644
--- a/src/tests/regression/issue3_test.go
+++ b/src/tests/regression/issue3_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue3(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	class TestClass
 	{
 		/** get always returns "." */
diff --git a/src/tests/regression/issue497_test.go b/src/tests/regression/issue497_test.go
index 5a8a53e8f..fdff3fd43 100644
--- a/src/tests/regression/issue497_test.go
+++ b/src/tests/regression/issue497_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue497(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 class T {}
 
 /**
diff --git a/src/tests/regression/issue547_test.go b/src/tests/regression/issue547_test.go
index 3e6b097d4..97e6b2c40 100644
--- a/src/tests/regression/issue547_test.go
+++ b/src/tests/regression/issue547_test.go
@@ -10,6 +10,7 @@ func TestIssue547(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/standard/standard_3.php`}
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 putenv("A=1");
 \putenv("B=2");
 `)
diff --git a/src/tests/regression/issue548_test.go b/src/tests/regression/issue548_test.go
index 71051b916..70c9078fb 100644
--- a/src/tests/regression/issue548_test.go
+++ b/src/tests/regression/issue548_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue548_1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 class A {
   private $value;
   private function method() {}
@@ -37,6 +38,7 @@ class C extends B {
 func TestIssue548_2(t *testing.T) {
 	// Like TestIssue548, but with different names and types order.
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class C {
   private $value;
   private function method() {}
@@ -65,6 +67,7 @@ class A extends B {
 
 func TestIssue548_Magic(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class A {
   public function __call($method, $args) {}
   public function __get($prop) {}
@@ -85,6 +88,7 @@ class B extends A {
 
 func TestIssue548_Trait1(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class A {
   private $value;
   private function method() {}
@@ -112,6 +116,7 @@ class B {
 
 func TestIssue548_Trait2(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 class B {
   private $value;
   private function method() {}
diff --git a/src/tests/regression/issue556_test.go b/src/tests/regression/issue556_test.go
index 2b5259f8c..33a4d0bd2 100644
--- a/src/tests/regression/issue556_test.go
+++ b/src/tests/regression/issue556_test.go
@@ -10,6 +10,7 @@ func TestIssue556(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.LoadStubs = []string{`stubs/phpstorm-stubs/Core/Core_c.php`}
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 /**
  * @param \ArrayAccess|array $v
  */
diff --git a/src/tests/regression/issue673_test.go b/src/tests/regression/issue673_test.go
index 585d6fe09..a8fa95c00 100644
--- a/src/tests/regression/issue673_test.go
+++ b/src/tests/regression/issue673_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue673(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 $_ = ['\n' => 1, "\n" => 2];
 `)
 }
diff --git a/src/tests/regression/issue6_test.go b/src/tests/regression/issue6_test.go
index cad278d7a..128505fae 100644
--- a/src/tests/regression/issue6_test.go
+++ b/src/tests/regression/issue6_test.go
@@ -8,7 +8,8 @@ import (
 
 func TestIssue6(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
-	declare(strict_types=1);
+	declare(strict_types = 1);
+	declare(strict_types = 1);
 
 	trait Example
 	{
diff --git a/src/tests/regression/issue778_test.go b/src/tests/regression/issue778_test.go
index aa02c0785..5053c3ebb 100644
--- a/src/tests/regression/issue778_test.go
+++ b/src/tests/regression/issue778_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue778(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 trait FooStatic {
     /** @return void */
     public static function f() {
diff --git a/src/tests/regression/issue78_test.go b/src/tests/regression/issue78_test.go
index 1bb38a1f3..98e5f2ed2 100644
--- a/src/tests/regression/issue78_test.go
+++ b/src/tests/regression/issue78_test.go
@@ -9,6 +9,7 @@ import (
 func TestIssue78_1(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+	declare(strict_types = 1);
 global $cond;
 $xs = [1, 2];
 switch ($cond) {
@@ -202,6 +203,7 @@ function trailing_exit_while($xs) {
 func TestIssue78_2(t *testing.T) {
 	test := linttest.NewSuite(t)
 	test.AddFile(`<?php
+declare(strict_types = 1);
 global $cond;
 $xs = [1, 2];
 switch ($cond) {
@@ -382,6 +384,7 @@ function trailing_exit_while($xs) {
 
 func TestIssue78_3(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 $xs = [1, 2];
 trailing_exit_if($xs);
 trailing_exit_foreach($xs);
diff --git a/src/tests/regression/issue8_test.go b/src/tests/regression/issue8_test.go
index b90cb3701..c10f07a76 100644
--- a/src/tests/regression/issue8_test.go
+++ b/src/tests/regression/issue8_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue8(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 	class Magic
 	{
 		public function __get($a);
diff --git a/src/tests/regression/issue989_test.go b/src/tests/regression/issue989_test.go
index 754f2ca4d..80c739976 100644
--- a/src/tests/regression/issue989_test.go
+++ b/src/tests/regression/issue989_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestIssue989TraitUse(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 trait Trait1 {}
 
 function f() {
@@ -24,6 +25,7 @@ function f() {
 
 func TestIssue989ScalarEncapsedStringVar(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
 function f() {
   $a = 100;
   return "Hello ${$a}";
@@ -33,6 +35,8 @@ function f() {
 
 func TestIssue989InterpretStrings(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+declare(strict_types = 1);
+declare(strict_types = 1);
 $unicode = "\u{0000000000aA19}";
 $unicode = "\u{00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000041}";
 `)
diff --git a/src/tests/regression/pull236_test.go b/src/tests/regression/pull236_test.go
index d1dc29c84..61093d846 100644
--- a/src/tests/regression/pull236_test.go
+++ b/src/tests/regression/pull236_test.go
@@ -8,6 +8,7 @@ import (
 
 func TestPull236(t *testing.T) {
 	linttest.SimpleNegativeTest(t, `<?php
+	declare(strict_types = 1);
 $_ = new class {
   private function f() { return 10; }