From a442fad3b7995dff53869a56eb5d6f3aa462223e Mon Sep 17 00:00:00 2001
From: Boshen <boshenc@gmail.com>
Date: Tue, 24 Oct 2023 17:25:12 +0800
Subject: [PATCH] feat(semantic): bind function expression name (#1049)

closes #1018

We'll eventually recover the mangling tests, which should cover this
change.
---
 crates/oxc_semantic/src/binder.rs | 10 ++++++++++
 tasks/coverage/src/test262.rs     | 26 +++++---------------------
 2 files changed, 15 insertions(+), 21 deletions(-)

diff --git a/crates/oxc_semantic/src/binder.rs b/crates/oxc_semantic/src/binder.rs
index 4eba646cb..029380ab5 100644
--- a/crates/oxc_semantic/src/binder.rs
+++ b/crates/oxc_semantic/src/binder.rs
@@ -138,6 +138,16 @@ impl<'a> Binder for Function<'a> {
                     excludes,
                 );
                 ident.symbol_id.set(Some(symbol_id));
+            } else if self.r#type == FunctionType::FunctionExpression {
+                // https://tc39.es/ecma262/#sec-runtime-semantics-instantiateordinaryfunctionexpression
+                // 5. Perform ! funcEnv.CreateImmutableBinding(name, false).
+                let symbol_id = builder.declare_symbol(
+                    ident.span,
+                    &ident.name,
+                    SymbolFlags::empty(),
+                    SymbolFlags::empty(),
+                );
+                ident.symbol_id.set(Some(symbol_id));
             }
         }
 
diff --git a/tasks/coverage/src/test262.rs b/tasks/coverage/src/test262.rs
index c899eef86..789d3a42a 100644
--- a/tasks/coverage/src/test262.rs
+++ b/tasks/coverage/src/test262.rs
@@ -203,7 +203,7 @@ impl Case for Test262Case {
 }
 
 fn are_all_identifiers_resolved(semantic: &oxc_semantic::Semantic<'_>) -> bool {
-    use oxc_ast::{ast, AstKind};
+    use oxc_ast::AstKind;
     use oxc_semantic::AstNode;
 
     let ast_nodes = semantic.nodes();
@@ -212,27 +212,11 @@ fn are_all_identifiers_resolved(semantic: &oxc_semantic::Semantic<'_>) -> bool {
             AstKind::BindingIdentifier(id) => {
                 let mut parents = ast_nodes.iter_parents(node.id()).map(AstNode::kind);
                 parents.next(); // Exclude BindingIdentifier itself
-                match parents.next() {
-                    Some(AstKind::Function(func))
-                        if func.r#type == ast::FunctionType::FunctionExpression =>
-                    {
-                        // FIXME: Currently, the name of `FunctionExpression` won't be assigned a `SymbolId`
-                        return false;
-                    }
-                    _ => {}
+                if let (Some(AstKind::Function(_)), Some(AstKind::IfStatement(_))) =
+                    (parents.next(), parents.next())
+                {
+                    return false;
                 }
-                let mut parents = ast_nodes.iter_parents(node.id()).map(AstNode::kind);
-                parents.next(); // Exclude BindingIdentifier itself
-                match (parents.next(), parents.next()) {
-                    // FIXME: case like `if (xx) ; else function test() {}`
-                    (Some(AstKind::Function(func)), Some(AstKind::IfStatement(_)))
-                        if func.r#type == ast::FunctionType::FunctionDeclaration =>
-                    {
-                        return false;
-                    }
-                    _ => {}
-                }
-
                 id.symbol_id.get().is_none()
             }
             AstKind::IdentifierReference(ref_id) => ref_id.reference_id.get().is_none(),