fix: skip method scope for decorator expressions

babel · Mar 22, 2022 · 5717af3 · 5717af3
1 parent a3a8e10
commit 5717af3
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Showing 3 changed files with 36 additions and 5 deletions.
diff --git a/packages/babel-traverse/src/path/context.ts b/packages/babel-traverse/src/path/context.ts
@@ -132,8 +132,13 @@ export function setScope(this: NodePath) {
 
   let path = this.parentPath;
 
-  // Skip method scope if is computed method key
-  if (this.key === "key" && path.isMethod()) path = path.parentPath;
+  // Skip method scope if is computed method key or decorator expression
+  if (
+    (this.key === "key" || this.listKey === "decorators") &&
+    path.isMethod()
+  ) {
+    path = path.parentPath;
+  }
 
   let target;
   while (path && !target) {

diff --git a/packages/babel-traverse/src/scope/index.ts b/packages/babel-traverse/src/scope/index.ts
@@ -419,10 +419,10 @@ export default class Scope {
     let parent,
       path = this.path;
     do {
-      // Skip method scope if coming from inside computed key
-      const isKey = path.key === "key";
+      // Skip method scope if coming from inside computed key or decorator expression
+      const shouldSkip = path.key === "key" || path.listKey === "decorators";
       path = path.parentPath;
-      if (isKey && path.isMethod()) path = path.parentPath;
+      if (shouldSkip && path.isMethod()) path = path.parentPath;
       if (path && path.isScope()) parent = path;
     } while (path && !parent);
 

diff --git a/packages/babel-traverse/test/scope.js b/packages/babel-traverse/test/scope.js
@@ -256,6 +256,32 @@ describe("scope", () => {
       });
     });
 
+    describe("decorator", () => {
+      const parserOptions = {
+        plugins: [["decorators", { decoratorsBeforeExport: true }]],
+      };
+      it("should not have visibility of declarations inside method body", () => {
+        expect(
+          getPath(
+            `var a = "outside"; class foo { @(() => () => a) m() { let a = "inside"; } }`,
+            parserOptions,
+          )
+            .get("body.1.body.body.0.decorators.0.expression.body.body")
+            .scope.getBinding("a").path.node.init.value,
+        ).toBe("outside");
+      });
+      it("should not have visibility on parameter bindings", () => {
+        expect(
+          getPath(
+            `var a = "outside"; class foo { @(() => () => a) m(a = "inside") {} }`,
+            parserOptions,
+          )
+            .get("body.1.body.body.0.decorators.0.expression.body.body")
+            .scope.getBinding("a").path.node.init.value,
+        ).toBe("outside");
+      });
+    });
+
     it("variable declaration", function () {
       expect(getPath("var foo = null;").scope.getBinding("foo").path.type).toBe(
         "VariableDeclarator",