libnixf/Sema: differentiate lambda argument with and without formals

nix-community · Jul 31, 2024 · d2a05f3 · d2a05f3
1 parent 4c306e7
commit d2a05f3
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Showing 3 changed files with 24 additions and 3 deletions.
diff --git a/libnixf/include/nixf/Sema/VariableLookup.h b/libnixf/include/nixf/Sema/VariableLookup.h
@@ -39,6 +39,9 @@ class Definition {
     /// \brief From lambda formal, e.g. { a }: a + 1
     DS_LambdaFormal,
 
+    /// \brief From lambda arg with formal, e.g. { foo, bar }@a: a + 1
+    DS_LambdaArgWithFormal,
+
     /// \brief From recursive attribute set.  e.g. rec { }
     DS_Rec,
 

diff --git a/libnixf/src/Sema/VariableLookup.cpp b/libnixf/src/Sema/VariableLookup.cpp
@@ -129,11 +129,16 @@ void VariableLookupAnalysis::dfs(const ExprLambda &Lambda,
   // foo: body
   // ^~~<------- add function argument.
   if (Arg.id()) {
-    // Function arg cannot duplicate to it's formal.
-    // If it this unluckily happens, we would like to skip this definition.
-    if (!Arg.formals() || !Arg.formals()->dedup().contains(Arg.id()->name()))
+    if (!Arg.formals()) {
       ToDef.insert_or_assign(Arg.id(), DBuilder.add(Arg.id()->name(), Arg.id(),
                                                     Definition::DS_LambdaArg));
+      // Function arg cannot duplicate to it's formal.
+      // If it this unluckily happens, we would like to skip this definition.
+    } else if (!Arg.formals()->dedup().contains(Arg.id()->name())) {
+      ToDef.insert_or_assign(Arg.id(),
+                             DBuilder.add(Arg.id()->name(), Arg.id(),
+                                          Definition::DS_LambdaArgWithFormal));
+    }
   }
 
   // { foo, bar, ... } : body

diff --git a/libnixf/test/Sema/VariableLookup.cpp b/libnixf/test/Sema/VariableLookup.cpp
@@ -172,6 +172,19 @@ TEST_F(VLATest, LivenessDupSymbol) {
   ASSERT_EQ(Diags[0].tags().size(), 0);
 }
 
+TEST_F(VLATest, LivenessArgWithFormal) {
+  std::shared_ptr<Node> AST = parse("{ foo }@bar: foo", Diags);
+  VariableLookupAnalysis VLA(Diags);
+  VLA.runOnAST(*AST);
+
+  ASSERT_EQ(Diags.size(), 1);
+
+  ASSERT_EQ(Diags[0].kind(), Diagnostic::DK_DefinitionNotUsed);
+  ASSERT_EQ(Diags[0].range().lCur().column(), 8);
+  ASSERT_EQ(Diags[0].tags().size(), 1);
+  ASSERT_EQ(Diags[0].tags()[0], DiagnosticTag::Faded);
+}
+
 TEST_F(VLATest, ToDefAttrs) {
   std::shared_ptr<Node> AST = parse("rec { x = 1; y = x; z = x; }", Diags);
   VariableLookupAnalysis VLA(Diags);