fix(semantic/cfg): discrete finalization path after NewFunctions. (#…

…3671)

closes #3668

[oxlint-ecosystem-ci](https://github.com/rzvxa/oxlint-ecosystem-ci/actions/runs/9512489987/job/26220576138)

For this code:

```js
function f() {
    try {
        return a();
    }
    catch (err) {
        throw new class CustomError extends Error {
            constructor() {
                super(err);
            }
        };
    }
    finally {
        this.b();
    }
}

```

We went from this:
![image](https://github.com/oxc-project/oxc/assets/3788964/bcb751aa-50cf-4c0a-8975-e01697ff78b2)

To this:
![Screenshot 2024-06-14 110805](https://github.com/oxc-project/oxc/assets/3788964/03a03525-5326-47b1-8d6c-69720f7f3149)

crates/oxc_linter/src/rules/eslint/no_this_before_super.rs

@@ -273,6 +273,24 @@ fn test() {
         // allows `this`/`super` after `super()`.
         ("class A extends B { }", None),
         ("class A extends B { constructor() { super(); } }", None),
+        (
+        "
+        function f() {
+            try {
+                return a();
+            }
+            catch (err) {
+                throw new class CustomError extends Error {
+                    constructor() {
+                        super(err);
+                    }
+                };
+            }
+            finally {
+                this.b();
+            }
+        }
+        ", None),
         ("class A extends B { constructor() { super(); this.c = this.d; } }", None),
         ("class A extends B { constructor() { super(); this.c(); } }", None),
         ("class A extends B { constructor() { super(); super.c(); } }", None),

crates/oxc_semantic/src/builder.rs

@@ -1367,6 +1367,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
 
         /* cfg */
         let before_function_graph_ix = self.cfg.current_node_ix;
+        self.cfg.push_finalization_stack();
         let error_harness = self.cfg.attach_error_harness(ErrorEdgeKind::Implicit);
         let function_graph_ix = self.cfg.new_basic_block_function();
         self.cfg.ctx(None).new_function();
@@ -1391,6 +1392,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
         /* cfg */
         self.cfg.ctx(None).resolve_expect(CtxFlags::FUNCTION);
         self.cfg.release_error_harness(error_harness);
+        self.cfg.pop_finalization_stack();
         let after_function_graph_ix = self.cfg.new_basic_block_normal();
         self.cfg.add_edge(before_function_graph_ix, after_function_graph_ix, EdgeType::Normal);
         /* cfg */
@@ -1463,6 +1465,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
 
         /* cfg */
         let current_node_ix = self.cfg.current_node_ix;
+        self.cfg.push_finalization_stack();
         let error_harness = self.cfg.attach_error_harness(ErrorEdgeKind::Implicit);
         let function_graph_ix = self.cfg.new_basic_block_function();
         self.cfg.ctx(None).new_function();
@@ -1483,6 +1486,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
         /* cfg */
         self.cfg.ctx(None).resolve_expect(CtxFlags::FUNCTION);
         self.cfg.release_error_harness(error_harness);
+        self.cfg.pop_finalization_stack();
         self.cfg.current_node_ix = current_node_ix;
         /* cfg */
         if let Some(parameters) = &expr.type_parameters {

crates/oxc_semantic/src/control_flow/builder/mod.rs

@@ -23,7 +23,7 @@ pub struct ControlFlowGraphBuilder<'a> {
     /// Contains the error unwinding path represented as a stack of `ErrorHarness`es
     error_path: Vec<ErrorHarness>,
     /// Stack of finalizers, the top most element is always the appropriate one for current node.
-    finalizers: Vec<BasicBlockId>,
+    finalizers: Vec<Option<BasicBlockId>>,
 }
 
 impl<'a> ControlFlowGraphBuilder<'a> {
@@ -81,7 +81,7 @@ impl<'a> ControlFlowGraphBuilder<'a> {
             self.error_path.last().expect("normal basic blocks need an error harness to attach to");
         self.add_edge(graph_ix, *error_graph_ix, EdgeType::Error(*error_edge_kind));
 
-        if let Some(finalizer) = self.finalizers.last() {
+        if let Some(Some(finalizer)) = self.finalizers.last() {
             self.add_edge(graph_ix, *finalizer, EdgeType::Finalize);
         }
 
@@ -139,16 +139,26 @@ impl<'a> ControlFlowGraphBuilder<'a> {
     /// Returns the `BasicBlockId` of the created finalizer block.
     pub fn attach_finalizer(&mut self) -> BasicBlockId {
         let graph_ix = self.new_basic_block();
-        self.finalizers.push(graph_ix);
+        self.finalizers.push(Some(graph_ix));
         graph_ix
     }
 
+    pub fn push_finalization_stack(&mut self) {
+        self.finalizers.push(None);
+    }
+
+    pub fn pop_finalization_stack(&mut self) {
+        let result = self.finalizers.pop();
+        debug_assert!(result.as_ref().is_some_and(Option::is_none));
+    }
+
     /// # Panics if last finalizer doesn't match the expected `BasicBlockId`.
     pub fn release_finalizer(&mut self, expect: BasicBlockId) {
         // return early if there is no finalizer.
         let Some(finalizer) = self.finalizers.pop() else { return };
         assert_eq!(
-            finalizer, expect,
+            finalizer,
+            Some(expect),
             "expected finalizer doesn't match the last finalizer pushed onto the stack."
         );
     }