Classes: Add more tests for prototype edge cases

test/mjsunit/harmony/classes.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --harmony
 
 (function TestBasics() {
   var C = class C {}
   assertEquals(typeof C, 'function');
   assertEquals(C.__proto__, Function.prototype);
@@ skipping 156 matching lines @@
 
 
 function assertMethodDescriptor(object, name) {
   var descr = Object.getOwnPropertyDescriptor(object, name);
   assertTrue(descr.configurable);
   assertTrue(descr.enumerable);
   assertTrue(descr.writable);
   assertEquals('function', typeof descr.value);
 }
 
+
 function assertGetterDescriptor(object, name) {
   var descr = Object.getOwnPropertyDescriptor(object, name);
   assertTrue(descr.configurable);
   assertTrue(descr.enumerable);
   assertEquals('function', typeof descr.get);
   assertEquals(undefined, descr.set);
 }
 
 
 function assertSetterDescriptor(object, name) {
@@ skipping 193 matching lines @@
     }
     static staticM() {
       return 2;
     }
   }
 
   assertEquals(1, new C().m());
   assertEquals(2, C.staticM());
 })();
 
+
+(function TestConstructableButNoPrototype() {
+  var Base = function() {}.bind();
+  assertThrows(function() {
+    class C extends Base {}
+  }, TypeError);
+})();
+
+
+(function TestPrototypeGetter() {
+  var calls = 0;
+  var Base = function() {}.bind();
+  Object.defineProperty(Base, 'prototype', {
+    get: function() {
+      calls++;
+      return null;
+    },
+    configurable: true
+  });
+  class C extends Base {}
+  assertEquals(1, calls);
+
+  calls = 0;
+  Object.defineProperty(Base, 'prototype', {
+    get: function() {
+      calls++;
+      return 42;
+    },
+    configurable: true
+  });
+  assertThrows(function() {
+    class C extends Base {}
+  }, TypeError);
+  assertEquals(1, calls);
+})();
+
+
+(function TestPrototypeSetter() {
+  var Base = function() {}.bind();
+  Object.defineProperty(Base, 'prototype', {
+    set: function() {
+      assertUnreachable();
+    }
+  });
+  assertThrows(function() {
+    class C extends Base {}
+  }, TypeError);
+})();
+
+
 /* TODO(arv): Implement
 (function TestNameBindingInConstructor() {
   class C {
     constructor() {
       assertThrows(function() {
         C = 42;
       }, ReferenceError);
     }
   }
   new C();
 })();
 */