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

joeldenning · Nov 22, 2018 · f3a3925 · f3a3925
1 parent 61c1c77
commit f3a3925
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Showing 3 changed files with 30 additions and 9 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 +15,12 @@ class Foo extends function () {} {
     };
 
     if (true) {
-      console.log(_this2 = super(), foo());
+      var _temp;
+
+      console.log((_temp = super(), _this2 = this, _temp), 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
@@ -461,8 +461,12 @@ function getThisBinding(thisEnvFn, inConstructor) {
         if (supers.has(child.node)) return;
         supers.add(child.node);
 
-        child.replaceWith(
-          t.assignmentExpression("=", t.identifier(thisBinding), child.node),
+        child.insertAfter(
+          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
@@ -82,7 +82,11 @@ describe("arrow function conversion", () => {
       () => this;
     `,
       `
-      var _supercall = (..._args) => _this = super(..._args),
+      var _supercall = (..._args) => {
+        var _temp;
+
+        return _temp = super(..._args), _this = this, _temp;
+      },
           _this;
 
       (function () {
@@ -115,9 +119,14 @@ describe("arrow function conversion", () => {
       (function () {
         _this;
       });
-      _this = super();
+      super();
+      _this = this;
       this;
-      () => _this = super();
+      () => {
+        var _temp;
+
+        return _temp = super(), _this = this, _temp;
+      }
       () => this;
     `,
       { methodName: "constructor", extend: true },
@@ -144,9 +153,14 @@ describe("arrow function conversion", () => {
 
         _this;
       }).bind(_arrowCheckId);
-      _this = super();
+      super();
+      _this = this;
       this;
-      () => _this = super();
+      () => {
+        var _temp;
+
+        return _temp = super(), _this = this, _temp;
+      }
       () => this;
     `,
       {