Fix dce: don't remove fn param from setters (close #267) (#270)

babel · Nov 14, 2016 · be82668 · be82668
2 parents bd10724 + 2ec0e2f
commit be82668
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diff --git a/packages/babel-plugin-minify-dead-code-elimination/__tests__/dead-code-elimination-test.js b/packages/babel-plugin-minify-dead-code-elimination/__tests__/dead-code-elimination-test.js
@@ -2209,4 +2209,20 @@ describe("dce-plugin", () => {
     `);
     expect(transform(source)).toBe(expected);
   });
+  it("should NOT remove fn params for setters", () => {
+    const source = unpad(`
+      function foo() {
+        var x = {
+          set a(b) {}
+        };
+        class A {
+          set c(d) {
+            x.a = 5;
+          }
+        }
+        return new A();
+      }
+    `);
+    expect(transform(source)).toBe(source);
+  });
 });
diff --git a/packages/babel-plugin-minify-dead-code-elimination/src/index.js b/packages/babel-plugin-minify-dead-code-elimination/src/index.js
@@ -108,7 +108,8 @@ module.exports = ({ types: t, traverse }) => {
 
         // if the scope is created by a function, we obtain its
         // parameter list
-        const paramsList = path.isFunction() ? path.get("params") : [];
+        const canRemoveParams = path.isFunction() && path.node.kind !== "set";
+        const paramsList = canRemoveParams ? path.get("params") : [];
 
         for (let i = paramsList.length - 1; i >= 0; i--) {
           const param = paramsList[i];