Bug 1166950 - Only give constructor functions a prototype. r=efaust

js/src/jsfun.cpp

@@ -443,16 +443,19 @@ fun_resolve(JSContext* cx, HandleObject obj, HandleId id, bool* resolvedp)
          * or (Object.prototype, Function.prototype, etc.) have that property
          * created eagerly.
          *
-         * ES5 15.3.4: the non-native function object named Function.prototype
-         * does not have a .prototype property.
-         *
          * ES5 15.3.4.5: bound functions don't have a prototype property. The
          * isBuiltin() test covers this case because bound functions are native
          * (and thus built-in) functions by definition/construction.
          *
-         * ES6 19.2.4.3: arrow functions also don't have a prototype property.
+         * In ES6 9.2.8 MakeConstructor the .prototype property is only assigned
+         * to constructors.
+         *
+         * Thus all of the following don't get a .prototype property:
+         * - Methods (that are not class-constructors or generators)
+         * - Arrow functions
+         * - Function.prototype
          */
-        if (fun->isBuiltin() || fun->isArrow() || fun->isFunctionPrototype())
+        if (fun->isBuiltin() || !fun->isConstructor())
             return true;
 
         if (!ResolveInterpretedFunctionPrototype(cx, fun))

js/src/tests/ecma_6/Class/methDefn.js

@@ -118,6 +118,10 @@ assertEq(b.enumerable, true);
 assertEq(b.writable, true);
 assertEq(b.value(), 4);
 
+// prototype property
+assertEq(a.b.prototype, undefined);
+assertEq(a.b.hasOwnProperty("prototype"), false);
+
 // Defining several methods using eval.
 var code = "({";
 for (i = 0; i < 1000; i++)

js/src/tests/ecma_6/Class/methDefnGen.js

@@ -66,6 +66,9 @@ assertEq(next.done, true);
 assertEq(next.value.hello, 2);
 assertEq(next.value.world, 3);
 
+// prototype property
+assertEq(b.g.hasOwnProperty("prototype"), true);
+
 // Strict mode
 a = {*b(c){"use strict";yield c;}};
 assertEq(a.b(1).next().value, 1);

js/src/tests/ecma_6/Class/methodsPrototype.js

@@ -0,0 +1,45 @@
+var test = `
+class TestClass {
+    constructor() { }
+    method() { }
+    get getter() { }
+    set setter(x) { }
+    *generator() { }
+    static staticMethod() { }
+    static get staticGetter() { }
+    static set staticSetter(x) { }
+    static *staticGenerator() { }
+}
+
+var test = new TestClass();
+
+var hasPrototype = [
+    test.constructor,
+    test.generator,
+    TestClass.staticGenerator
+]
+
+for (var fun of hasPrototype) {
+    assertEq(fun.hasOwnProperty('prototype'), true);
+}
+
+var hasNoPrototype = [
+    test.method,
+    Object.getOwnPropertyDescriptor(test.__proto__, 'getter').get,
+    Object.getOwnPropertyDescriptor(test.__proto__, 'setter').set,
+    TestClass.staticMethod,
+    Object.getOwnPropertyDescriptor(TestClass, 'staticGetter').get,
+    Object.getOwnPropertyDescriptor(TestClass, 'staticSetter').set,
+]
+
+for (var fun of hasNoPrototype) {
+    assertEq(fun.hasOwnProperty('prototype'), false);
+}
+
+`;
+
+if (classesEnabled())
+    eval(test);
+
+if (typeof reportCompare === "function")
+    reportCompare(0, 0, "OK");