libnixf/Parse: parse incomplete attrsets to provide completions (#644)

Small DX adjustments: - Parser distinguishes a little better formals from attrsets - Completion are triggered when discovering options of an attrset ( no need to try and guess the first letter ) --------- Co-authored-by: Yingchi Long <[email protected]>
nix-community · Jan 15, 2025 · 2c25600 · 2c25600
1 parent 6e58141
commit 2c25600
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Showing 2 changed files with 181 additions and 11 deletions.
diff --git a/libnixf/src/Parse/ParseExpr.cpp b/libnixf/src/Parse/ParseExpr.cpp
@@ -71,7 +71,7 @@ std::shared_ptr<Expr> Parser::parseExprApp(int Limit) {
 }
 
 std::shared_ptr<Expr> Parser::parseExpr() {
-  // Look ahead 3 tokens.
+  // Look ahead 4 tokens.
   switch (peek().kind()) {
   case tok_id: {
     switch (peek(1).kind()) {
@@ -93,8 +93,15 @@ std::shared_ptr<Expr> Parser::parseExpr() {
       case tok_comma:    // { a ,
       case tok_id:       // { a b
       case tok_ellipsis: // { a ...
-      case tok_r_curly:
         return parseExprLambda();
+      case tok_r_curly:
+        switch (peek(3).kind()) {
+        case tok_colon: // { a } :
+        case tok_at:    // { a } @
+          return parseExprLambda();
+        default:
+          return parseExprAttrs();
+        }
       default:
         break;
       }

diff --git a/libnixf/test/Parse/ParseAttrs.cpp b/libnixf/test/Parse/ParseAttrs.cpp
@@ -223,25 +223,188 @@ TEST(Parser, AttrsBinding) {
 }
   )"sv;
 
+  std::vector<Diagnostic> Diags;
+  auto AST = nixf::parse(Src, Diags);
+  ASSERT_TRUE(AST);
+  ASSERT_EQ(Diags.size(), 0);
+
+  ASSERT_EQ(AST->kind(), Node::NK_ExprAttrs);
+
+  ASSERT_EQ(AST->range().lCur().line(), 1);
+  ASSERT_EQ(AST->range().lCur().column(), 0);
+  ASSERT_EQ(AST->range().rCur().line(), 4);
+  ASSERT_EQ(AST->range().rCur().column(), 1);
+
+  const auto &Attrs = *static_cast<ExprAttrs *>(AST.get());
+  const auto &Bindings = Attrs.binds()->bindings();
+
+  ASSERT_EQ(Bindings.size(), 2);
+
+  ASSERT_EQ(Bindings[0]->range().lCur().line(), 2);
+  ASSERT_EQ(Bindings[0]->range().lCur().column(), 2);
+  ASSERT_EQ(Bindings[0]->range().rCur().line(), 2);
+  ASSERT_EQ(Bindings[0]->range().rCur().column(), 8);
+
+  ASSERT_EQ(Bindings[1]->range().lCur().line(), 3);
+  ASSERT_EQ(Bindings[1]->range().lCur().column(), 2);
+  ASSERT_EQ(Bindings[1]->range().rCur().line(), 3);
+  ASSERT_EQ(Bindings[1]->range().rCur().column(), 8);
+}
+
+TEST(Parser, AttrsBindingWriting) {
+  auto Src = R"(
+{
+  a
+}
+  )"sv;
+
+  std::vector<Diagnostic> Diags;
+  auto AST = nixf::parse(Src, Diags);
+
+  ASSERT_TRUE(AST);
+  ASSERT_EQ(AST->kind(), Node::NK_ExprAttrs);
+
+  const auto &Attrs = *static_cast<ExprAttrs *>(AST.get());
+  ASSERT_EQ(Attrs.binds()->bindings().size(), 1);
+
+  const auto &Bind =
+      *static_cast<Binding *>(Attrs.binds()->bindings()[0].get());
+
+  ASSERT_EQ(Bind.kind(), Node::NK_Binding);
+
+  const auto &BindPath = Bind.path();
+  ASSERT_EQ(BindPath.names().size(), 1);
+
+  const auto &Name = *BindPath.names().at(0);
+
+  ASSERT_EQ(Name.kind(), Node::NK_Interpolation);
+  ASSERT_EQ(Name.id()->kind(), Node::NK_Identifier);
+  ASSERT_EQ(Name.id()->name(), "a");
+
+  ASSERT_EQ(Name.range().lCur().line(), 2);
+  ASSERT_EQ(Name.range().lCur().column(), 2);
+  ASSERT_EQ(Name.range().rCur().line(), 2);
+  ASSERT_EQ(Name.range().rCur().column(), 3);
+}
+
+TEST(Parser, AttrsBindingWritingDot) {
+  auto Src = R"(
+{
+  a.
+}
+  )"sv;
+
+  std::vector<Diagnostic> Diags;
+  auto AST = nixf::parse(Src, Diags);
+
+  ASSERT_TRUE(AST);
+  ASSERT_EQ(AST->kind(), Node::NK_ExprAttrs);
+
+  const auto &Attrs = *static_cast<ExprAttrs *>(AST.get());
+  ASSERT_EQ(Attrs.binds()->bindings().size(), 1);
+
+  const auto &Bind =
+      *static_cast<Binding *>(Attrs.binds()->bindings()[0].get());
+
+  ASSERT_EQ(Bind.kind(), Node::NK_Binding);
+
+  const auto &Path = Bind.path();
+  ASSERT_EQ(Path.names().size(), 1);
+
+  const auto &Name = *Path.names().at(0);
+
+  ASSERT_EQ(Name.kind(), Node::NK_Interpolation);
+  ASSERT_EQ(Name.id()->kind(), Node::NK_Identifier);
+  ASSERT_EQ(Name.id()->name(), "a");
+
+  ASSERT_EQ(Name.range().lCur().line(), 2);
+  ASSERT_EQ(Name.range().lCur().column(), 2);
+  ASSERT_EQ(Name.range().rCur().line(), 2);
+  ASSERT_EQ(Name.range().rCur().column(), 3);
+}
+
+TEST(Parser, AttrsNestedInLambda) {
+  auto Src = R"(
+{...}: {
+  a = {
+    b = 1;
+  };
+}
+  )"sv;
+
+  std::vector<Diagnostic> Diags;
+  auto AST = nixf::parse(Src, Diags);
+
+  ASSERT_TRUE(AST);
+  ASSERT_EQ(AST->kind(), Node::NK_ExprLambda);
+
+  ASSERT_EQ(AST->range().lCur().line(), 1);
+  ASSERT_EQ(AST->range().lCur().column(), 0);
+  ASSERT_EQ(AST->range().rCur().line(), 5);
+  ASSERT_EQ(AST->range().rCur().column(), 1);
+
+  ASSERT_EQ(Diags.size(), 0);
+
+  const auto &Attrs =
+      static_cast<ExprAttrs *>(static_cast<ExprLambda *>(AST.get())->body());
+  ASSERT_EQ(Attrs->kind(), Node::NK_ExprAttrs);
+
+  const auto &Bind =
+      static_cast<Binding *>(Attrs->binds()->bindings()[0].get());
+
+  ASSERT_EQ(Bind->kind(), Node::NK_Binding);
+
+  const auto &NestedAttrs = static_cast<ExprAttrs *>(Bind->value().get());
+
+  ASSERT_EQ(NestedAttrs->kind(), Node::NK_ExprAttrs);
+}
+
+TEST(Parser, AttrsNested) {
+  auto Src = R"(
+{
+  a = {
+    b = 1;
+  };
+}
+  )"sv;
+
   std::vector<Diagnostic> Diags;
   auto AST = nixf::parse(Src, Diags);
 
   ASSERT_TRUE(AST);
   ASSERT_EQ(AST->kind(), Node::NK_ExprAttrs);
   ASSERT_TRUE(AST->range().lCur().isAt(1, 0, 1));
-  ASSERT_TRUE(AST->range().rCur().isAt(4, 1, 22));
+  ASSERT_TRUE(AST->range().rCur().isAt(5, 1, 28));
 
   ASSERT_EQ(Diags.size(), 0);
 
   // Check the bindings.
-  auto &B = *static_cast<ExprAttrs *>(AST.get());
-  assert(B.binds() && "expected bindings");
-  ASSERT_EQ(B.binds()->bindings().size(), 2);
-  ASSERT_TRUE(B.binds()->bindings()[0]->range().lCur().isAt(2, 2, 5));
-  ASSERT_TRUE(B.binds()->bindings()[0]->range().rCur().isAt(2, 8, 11));
-
-  ASSERT_TRUE(B.binds()->bindings()[1]->range().lCur().isAt(3, 2, 14));
-  ASSERT_TRUE(B.binds()->bindings()[1]->range().rCur().isAt(3, 8, 20));
+  const auto &B = static_cast<ExprAttrs *>(AST.get())->binds()->bindings();
+  ASSERT_EQ(B.size(), 1);
+
+  const auto &Ba = static_cast<Binding *>(B[0].get());
+
+  ASSERT_EQ(Ba->kind(), Node::NK_Binding);
+  ASSERT_TRUE(Ba->range().lCur().isAt(2, 2, 5));
+  ASSERT_TRUE(Ba->range().rCur().isAt(4, 4, 26));
+
+  ASSERT_EQ(Ba->path().names().at(0)->id()->name(), "a");
+  ASSERT_EQ(Ba->value()->kind(), Node::NK_ExprAttrs);
+
+  const auto &BaRHS =
+      static_cast<ExprAttrs *>(Ba->value().get())->binds()->bindings();
+  ASSERT_EQ(BaRHS.size(), 1);
+  ASSERT_EQ(BaRHS[0]->kind(), Node::NK_Binding);
+
+  const auto &BaRHSb = static_cast<Binding *>(BaRHS[0].get());
+
+  ASSERT_EQ(BaRHSb->range().lCur().line(), 3);
+  ASSERT_EQ(BaRHSb->range().lCur().column(), 4);
+  ASSERT_EQ(BaRHSb->range().rCur().line(), 3);
+  ASSERT_EQ(BaRHSb->range().rCur().column(), 10);
+
+  ASSERT_EQ(BaRHSb->path().names().at(0)->id()->name(), "b");
+  ASSERT_EQ(BaRHSb->value()->kind(), Node::NK_ExprInt);
 }
 
 TEST(Parser, AttrsBindingEarlyExit) {