fix(cfg): double resolution of labeled statements. (#4177)

rzvxa · rzvxa · commit 7a059ab53ac0 · 2024-07-11T01:39:28.000Z
Fixes #4173
diff --git a/crates/oxc_cfg/src/builder/context.rs b/crates/oxc_cfg/src/builder/context.rs
@@ -130,9 +130,12 @@ impl<'a, 'c> QueryCtx<'a, 'c> {
 
         self.resolve_ctx(ctx);
 
-        // mark the upper label continue jump point the same as ours,
+        // mark the upper label continue jump point the same as ours if it isn't already assigned,
+        // NOTE: if it is already assigned there's a resolution before this context.
         if let Some(jmp) = continue_jmp {
-            if let Some(label_ctx) = self.0.immediate_labeled_ctx() {
+            if let Some(label_ctx @ RefCtxCursor(Ctx { continue_jmp: None, .. })) =
+                self.0.immediate_labeled_ctx()
+            {
                 label_ctx.mark_continue(jmp);
             }
         }
diff --git a/crates/oxc_cfg/tests/builder.rs b/crates/oxc_cfg/tests/builder.rs
@@ -0,0 +1,38 @@
+use oxc_cfg::{ControlFlowGraphBuilder, CtxCursor};
+use oxc_syntax::node::AstNodeId;
+/// same as but just the skeleton
+/// ```js
+/// A: {
+///   do {} while (a);
+///   do {} while (b);
+///   break A;
+/// }
+/// ```
+#[test]
+fn labeled_statement_with_multiple_loops_continue_and_break() {
+    const A: Option<&str> = Some("A");
+
+    let mut cfg = ControlFlowGraphBuilder::default();
+    cfg.attach_error_harness(oxc_cfg::ErrorEdgeKind::Implicit);
+
+    // labeled block start
+    let labeled = cfg.new_basic_block_normal();
+    cfg.ctx(A).default().allow_break().allow_continue();
+
+    // loop context 1
+    let c1 = cfg.new_basic_block_normal();
+    cfg.ctx(None).default().allow_break().allow_continue();
+    cfg.ctx(None).mark_break(c1).mark_continue(c1).resolve_with_upper_label();
+
+    // loop context 2
+    let c2 = cfg.new_basic_block_normal();
+    cfg.ctx(None).default().allow_break().allow_continue();
+    cfg.ctx(None).mark_break(c2).mark_continue(c2).resolve_with_upper_label();
+
+    cfg.append_break(AstNodeId::dummy(), A);
+
+    // labeled block end
+    cfg.ctx(A).mark_break(labeled).resolve();
+
+    cfg.build();
+}

Original file line number	Diff line number	Diff line change
`@@ -130,9 +130,12 @@ impl<'a, 'c> QueryCtx<'a, 'c> {`
`130`	`130`
`131`	`131`	`self.resolve_ctx(ctx);`
`132`	`132`
`133`		`- // mark the upper label continue jump point the same as ours,`
	`133`	`+ // mark the upper label continue jump point the same as ours if it isn't already assigned,`
	`134`	`+ // NOTE: if it is already assigned there's a resolution before this context.`
`134`	`135`	`if let Some(jmp) = continue_jmp {`
`135`		`- if let Some(label_ctx) = self.0.immediate_labeled_ctx() {`
	`136`	`+ if let Some(label_ctx @ RefCtxCursor(Ctx { continue_jmp: None, .. })) =`
	`137`	`+ self.0.immediate_labeled_ctx()`
	`138`	`+ {`
`136`	`139`	`label_ctx.mark_continue(jmp);`
`137`	`140`	`}`
`138`	`141`	`}`