Not depending on return value of super(). Fixes #9020. (#9060)

* Not depending on return value of super(). Fixes #9020. * Feedback from nicolo-ribaudo * Feedback -- fixing bad call to replaceWithMultiple
babel · Dec 4, 2018 · d305419 · d305419
1 parent 8b132c0
commit d305419
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Showing 3 changed files with 19 additions and 11 deletions.
diff --git a/packages/babel-plugin-transform-arrow-functions/test/fixtures/arrow-functions/this/output.js b/packages/babel-plugin-transform-arrow-functions/test/fixtures/arrow-functions/this/output.js
@@ -15,9 +15,10 @@ class Foo extends function () {} {
     };
 
     if (true) {
-      console.log(_this2 = super(), foo());
+      console.log((super(), _this2 = this), foo());
     } else {
-      _this2 = super();
+      super();
+      _this2 = this;
       console.log(foo());
     }
   }

diff --git a/packages/babel-traverse/src/path/conversion.js b/packages/babel-traverse/src/path/conversion.js
@@ -461,9 +461,14 @@ function getThisBinding(thisEnvFn, inConstructor) {
         if (supers.has(child.node)) return;
         supers.add(child.node);
 
-        child.replaceWith(
-          t.assignmentExpression("=", t.identifier(thisBinding), child.node),
-        );
+        child.replaceWithMultiple([
+          child.node,
+          t.assignmentExpression(
+            "=",
+            t.identifier(thisBinding),
+            t.identifier("this"),
+          ),
+        ]);
       },
     });
   });

diff --git a/packages/babel-traverse/test/arrow-transform.js b/packages/babel-traverse/test/arrow-transform.js
@@ -82,8 +82,8 @@ describe("arrow function conversion", () => {
       () => this;
     `,
       `
-      var _supercall = (..._args) => _this = super(..._args),
-          _this;
+      var _supercall = (..._args) => (super(..._args), _this = this),
+        _this;
 
       (function () {
         _supercall(345);
@@ -115,9 +115,10 @@ describe("arrow function conversion", () => {
       (function () {
         _this;
       });
-      _this = super();
+      super();
+      _this = this;
       this;
-      () => _this = super();
+      () => (super(), _this = this);
       () => this;
     `,
       { methodName: "constructor", extend: true },
@@ -144,9 +145,10 @@ describe("arrow function conversion", () => {
 
         _this;
       }).bind(_arrowCheckId);
-      _this = super();
+      super();
+      _this = this;
       this;
-      () => _this = super();
+      () => (super(), _this = this);
       () => this;
     `,
       {