Add more type validation to codec.js

mojo/public/js/codec_unittests.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 define([
     "gin/test/expect",
     "mojo/public/js/codec",
     "mojo/public/interfaces/bindings/tests/rect.mojom",
     "mojo/public/interfaces/bindings/tests/sample_service.mojom",
     "mojo/public/interfaces/bindings/tests/test_structs.mojom",
   ], function(expect, codec, rect, sample, structs) {
   testBar();
   testFoo();
   testNamedRegion();
   testTypes();
   testAlign();
   testUtf8();
-  testArrayPointerValidation();
+  testTypedPointerValidation();
   this.result = "PASS";
 
   function testBar() {
     var bar = new sample.Bar();
     bar.alpha = 1;
     bar.beta = 2;
     bar.gamma = 3;
     bar.type = 0x08070605;
     bar.extraProperty = "banana";
 
@@ skipping 221 matching lines @@
     expect(actualMemory.length).toEqual(expectedMemory.length);
     expect(actualMemory).toEqual(expectedMemory);
 
     var reader = new codec.MessageReader(message);
     expect(reader.payloadSize).toBe(payloadSize);
     expect(reader.messageName).toBe(messageName);
     var str2 = reader.decoder.decodeStringPointer();
     expect(str2).toEqual(str);
   }
 
-  function testArrayPointerValidation() {
+  function testTypedPointerValidation() {
+    var encoder = new codec.MessageBuilder(42, 24).createEncoder(8);
     function DummyClass() {};
-    var builder = new codec.MessageBuilder(42, 24);
-    var encoder = builder.createEncoder(8);
-    expect(function() {
-      // Pass something that is not an array it should throw.
-      encoder.encodeArrayPointer(DummyClass, 75);
-    }).toThrow();
+    var testCases = [
+      // method, args, invalid examples, valid examples
+      [encoder.encodeArrayPointer, [DummyClass], [75], [[], null, undefined]],
+      [encoder.encodeStringPointer, [], [75, new String("foo")],
+          ["", "bar", null, undefined]],
+      [encoder.encodeMapPointer, [DummyClass, DummyClass], [75],
+          [new Map(), null, undefined]],
+    ];
 
-    // An empty array or null should do nothing and be fine.
-    encoder.encodeArrayPointer(DummyClass, []);
-    encoder.encodeArrayPointer(DummyClass, null);
+    testCases.forEach(function(test) {
+      var method = test[0];
+      var baseArgs = test[1];
+      var invalidExamples = test[2];
+      var validExamples = test[3];
+
+      var encoder = new codec.MessageBuilder(42, 24).createEncoder(8);
+      invalidExamples.forEach(function(invalid) {
+        expect(function() {
+          method.apply(encoder, baseArgs.concat(invalid));
+        }).toThrow();
+      });
+
+      validExamples.forEach(function(valid) {
+        var encoder = new codec.MessageBuilder(42, 24).createEncoder(8);
+        method.apply(encoder, baseArgs.concat(valid));
+      });
+    });
   }
 });