build(tests): require //go:build test tag if importing test packages outside of _test.go files

.golangci.yml

@@ -7,6 +7,11 @@ run:
   #   vendor$, third_party$, testdata$, examples$, Godeps$, builtin$
   skip-dirs-use-default: true
 
+  # Include non-test files tagged as test-only.
+  # Context: https://github.com/ava-labs/coreth/pull/597
+  build-tags:
+    - test
+
 linters:
   disable-all: true
   enable:

.vscode/settings.json

@@ -0,0 +1,11 @@
+{
+    "gopls": {
+        "build.buildFlags": [
+            // Context: https://github.com/ava-labs/avalanchego/pull/3173
+            // Without this tag, the language server won't build the test-only
+            // code in non-_test.go files.
+            "--tags='test'",
+        ],
+    },
+    "go.testTags": "test",
+}

core/state/test_statedb.go

@@ -1,6 +1,8 @@
 // (c) 2023, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package state
 
 import (

core/test_blockchain.go

@@ -1,6 +1,8 @@
 // (c) 2020-2021, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package core
 
 import (

precompile/testutils/test_config.go

@@ -1,6 +1,8 @@
 // (c) 2023, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package testutils
 
 import (

precompile/testutils/test_precompile.go

@@ -1,6 +1,8 @@
 // (c) 2023, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package testutils
 
 import (

precompile/testutils/test_predicate.go

@@ -1,6 +1,8 @@
 // (c) 2023, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package testutils
 
 import (

scripts/build_test.sh

@@ -15,4 +15,4 @@ source "$CORETH_PATH"/scripts/constants.sh
 
 # We pass in the arguments to this script directly to enable easily passing parameters such as enabling race detection,
 # parallelism, and test coverage.
-go test -shuffle=on -race -timeout="${TIMEOUT:-600s}" -coverprofile=coverage.out -covermode=atomic ./... "$@"
+go test --tags test -shuffle=on -race -timeout="${TIMEOUT:-600s}" -coverprofile=coverage.out -covermode=atomic ./... "$@"

scripts/lint_testing_in_non_test_files.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+# Ensure that files not named _test.go files but importing test-related packages
+# are constrained with `//go:build test`.
+
+ROOT=$( git rev-parse --show-toplevel )
+NON_TEST_GO_FILES=$( find "${ROOT}" -iname '*.go' ! -iname '*_test.go');
+
+IMPORT_TESTING=$( echo "${NON_TEST_GO_FILES}" | xargs grep -lP '^\s*(import\s+)?"testing"');
+IMPORT_TESTIFY=$( echo "${NON_TEST_GO_FILES}" | xargs grep -l '"github.com/stretchr/testify');
+# TODO(arr4n): send a PR to add support for build tags in `mockgen` and then enable this.
+# IMPORT_GOMOCK=$( echo "${NON_TEST_GO_FILES}" | xargs grep -l '"go.uber.org/mock');
+HAVE_TEST_LOGIC=$( printf "%s\n%s" "${IMPORT_TESTING}" "${IMPORT_TESTIFY}" );
+
+TAGGED_AS_TEST=$( echo "${NON_TEST_GO_FILES}" | xargs grep -lP '^\/\/go:build\s+(.+(,|\s+))?test[,\s]?');
+
+# -3 suppresses files that have test logic and have the "test" build tag
+# -2 suppresses files that are tagged despite not having detectable test logic
+UNTAGGED=$( comm -23 <( echo "${HAVE_TEST_LOGIC}" | sort -u ) <( echo "${TAGGED_AS_TEST}" | sort -u ) );
+if [ -z "${UNTAGGED}" ];
+then
+  exit 0;
+fi
+
+echo "Non-test Go files importing test-only packages MUST have '//go:build test' tag:";
+echo "${UNTAGGED}";
+exit 1;

sync/statesync/test_sync.go

@@ -1,6 +1,8 @@
 // (c) 2021-2022, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package statesync
 
 import (

sync/syncutils/test_trie.go

@@ -1,6 +1,8 @@
 // (c) 2021-2022, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:build test
+
 package syncutils
 
 import (