Add mojo bindings backpointer tests.

Simple bit-flipping won't generate negative offsets (e.g. large
positive offsets that overflow), so we add a test where we specifically
create the possibility of such.

Also simplify argument passing in the cpp -> js direction, since there isn't
a need to build lists here.  We're only interested in the other direction.

Remove some stray "explicit" keywords and reduce the echo
test iterations since it doesn't prove much.

Review URL: https://codereview.chromium.org/292243002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@271806 0039d316-1c4b-4281-b951-d872f2087c98

mojo/apps/js/test/js_to_cpp.mojom

@@ -30,17 +30,19 @@ struct EchoArgsList {
 
 interface CppSide {
   StartTest();  // Sent for all tests to notify that the JS side is now ready.
-  TestFinished();  // Sent in echo / bit-flip tests to indicate end.
+  TestFinished();  // Indicates end for echo, bit-flip, and back-pointer tests.
   PingResponse();
   EchoResponse(EchoArgsList list);
-  BitFlipResponse(EchoArgs arg);
+  BitFlipResponse(EchoArgsList arg);
+  BackPointerResponse(EchoArgsList arg);
 };
 
 [Client=CppSide]
 interface JsSide {
   Ping();
-  Echo(int32 numIterations, EchoArgsList list);
+  Echo(int32 numIterations, EchoArgs arg);
   BitFlip(EchoArgs arg);
+  BackPointer(EchoArgs arg);
 };
 
 }

mojo/apps/js/test/js_to_cpp_unittest.cc

@@ -126,12 +126,6 @@ void CheckSampleEchoArgs(const js_to_cpp::EchoArgs& arg) {
   CheckDataPipe(arg.data_handle().get().value());
 }
 
-js_to_cpp::EchoArgsList BuildSampleEchoArgsList() {
-  js_to_cpp::EchoArgsList::Builder builder;
-  builder.set_item(BuildSampleEchoArgs());
-  return builder.Finish();
-}
-
 void CheckSampleEchoArgsList(const js_to_cpp::EchoArgsList& list) {
   if (list.is_null())
     return;
@@ -154,6 +148,22 @@ void CheckCorruptedStringArray(const mojo::Array<mojo::String>& string_array) {
     CheckCorruptedString(string_array[i]);
 }
 
+void CheckCorruptedEchoArgs(const js_to_cpp::EchoArgs& arg) {
+  if (arg.is_null())
+    return;
+  CheckCorruptedString(arg.name());
+  CheckCorruptedStringArray(arg.string_array());
+  if (arg.data_handle().is_valid())
+    CheckDataPipe(arg.data_handle().get().value());
+}
+
+void CheckCorruptedEchoArgsList(const js_to_cpp::EchoArgsList& list) {
+  if (list.is_null())
+    return;
+  CheckCorruptedEchoArgs(list.item());
+  CheckCorruptedEchoArgsList(list.next());
+}
+
 // Base Provider implementation class. It's expected that tests subclass and
 // override the appropriate Provider functions. When test is done quit the
 // run_loop().
@@ -186,10 +196,14 @@ class CppSideConnection : public js_to_cpp::CppSide {
     NOTREACHED();
   }
 
-  virtual void BitFlipResponse(const js_to_cpp::EchoArgs& arg1) OVERRIDE {
+  virtual void BitFlipResponse(const js_to_cpp::EchoArgsList& list) OVERRIDE {
     NOTREACHED();
   }
 
+  virtual void BackPointerResponse(
+      const js_to_cpp::EchoArgsList& list) OVERRIDE {
+    NOTREACHED();
+  }
  protected:
   base::RunLoop* run_loop_;
   js_to_cpp::JsSide* js_side_;
@@ -201,7 +215,7 @@ class CppSideConnection : public js_to_cpp::CppSide {
 // Trivial test to verify a message sent from JS is received.
 class PingCppSideConnection : public CppSideConnection {
  public:
-  explicit PingCppSideConnection() : got_message_(false) {}
+  PingCppSideConnection() : got_message_(false) {}
   virtual ~PingCppSideConnection() {}
 
   // js_to_cpp::CppSide:
@@ -226,7 +240,7 @@ class PingCppSideConnection : public CppSideConnection {
 // Test that parameters are passed with correct values.
 class EchoCppSideConnection : public CppSideConnection {
  public:
-  explicit EchoCppSideConnection() :
+  EchoCppSideConnection() :
       message_count_(0),
       termination_seen_(false) {
   }
@@ -235,7 +249,7 @@ class EchoCppSideConnection : public CppSideConnection {
   // js_to_cpp::CppSide:
   virtual void StartTest() OVERRIDE {
     AllocationScope scope;
-    js_side_->Echo(kExpectedMessageCount, BuildSampleEchoArgsList());
+    js_side_->Echo(kExpectedMessageCount, BuildSampleEchoArgs());
   }
 
   virtual void EchoResponse(const js_to_cpp::EchoArgsList& list) OVERRIDE {
@@ -259,7 +273,7 @@ class EchoCppSideConnection : public CppSideConnection {
   }
 
  private:
-  static const int kExpectedMessageCount = 100;
+  static const int kExpectedMessageCount = 10;
   int message_count_;
   bool termination_seen_;
   DISALLOW_COPY_AND_ASSIGN(EchoCppSideConnection);
@@ -268,7 +282,7 @@ class EchoCppSideConnection : public CppSideConnection {
 // Test that corrupted messages don't wreak havoc.
 class BitFlipCppSideConnection : public CppSideConnection {
  public:
-  explicit BitFlipCppSideConnection() : termination_seen_(false) {}
+  BitFlipCppSideConnection() : termination_seen_(false) {}
   virtual ~BitFlipCppSideConnection() {}
 
   // js_to_cpp::CppSide:
@@ -277,13 +291,8 @@ class BitFlipCppSideConnection : public CppSideConnection {
     js_side_->BitFlip(BuildSampleEchoArgs());
   }
 
-  virtual void BitFlipResponse(const js_to_cpp::EchoArgs& arg) OVERRIDE {
-    if (arg.is_null())
-      return;
-    CheckCorruptedString(arg.name());
-    CheckCorruptedStringArray(arg.string_array());
-    if (arg.data_handle().is_valid())
-      CheckDataPipe(arg.data_handle().get().value());
+  virtual void BitFlipResponse(const js_to_cpp::EchoArgsList& list) OVERRIDE {
+    CheckCorruptedEchoArgsList(list);
   }
 
   virtual void TestFinished() OVERRIDE {
@@ -300,6 +309,37 @@ class BitFlipCppSideConnection : public CppSideConnection {
   DISALLOW_COPY_AND_ASSIGN(BitFlipCppSideConnection);
 };
 
+// Test that severely random messages don't wreak havoc.
+class BackPointerCppSideConnection : public CppSideConnection {
+ public:
+  BackPointerCppSideConnection() : termination_seen_(false) {}
+  virtual ~BackPointerCppSideConnection() {}
+
+  // js_to_cpp::CppSide:
+  virtual void StartTest() OVERRIDE {
+    AllocationScope scope;
+    js_side_->BackPointer(BuildSampleEchoArgs());
+  }
+
+  virtual void BackPointerResponse(
+      const js_to_cpp::EchoArgsList& list) OVERRIDE {
+    CheckCorruptedEchoArgsList(list);
+  }
+
+  virtual void TestFinished() OVERRIDE {
+    termination_seen_ = true;
+    run_loop()->Quit();
+  }
+
+  bool DidSucceed() {
+    return termination_seen_;
+  }
+
+ private:
+  bool termination_seen_;
+  DISALLOW_COPY_AND_ASSIGN(BackPointerCppSideConnection);
+};
+
 }  // namespace
 
 class JsToCppTest : public testing::Test {
@@ -363,5 +403,15 @@ TEST_F(JsToCppTest, DISABLED_BitFlip) {
   EXPECT_TRUE(cpp_side_connection.DidSucceed());
 }
 
+// TODO(tsepez): Disabled due to http://crbug.com/366797.
+TEST_F(JsToCppTest, DISABLED_BackPointer) {
+  if (IsRunningOnIsolatedBot())
+    return;
+
+  BackPointerCppSideConnection cpp_side_connection;
+  RunTest("mojo/apps/js/test/js_to_cpp_unittest", &cpp_side_connection);
+  EXPECT_TRUE(cpp_side_connection.DidSucceed());
+}
+
 }  // namespace js
 }  // namespace mojo

mojo/apps/js/test/js_to_cpp_unittest.js

@@ -29,14 +29,12 @@ define('mojo/apps/js/test/js_to_cpp_unittest', [
     this.cppSide_.pingResponse();
   };
 
-  JsSideConnection.prototype.echo = function (numIterations, list) {
-    var arg = list.item;
+  JsSideConnection.prototype.echo = function (numIterations, arg) {
     var dataPipe1;
     var dataPipe2;
     var i;
     var messagePipe1;
     var messagePipe2;
-    var resultList;
     var specialArg;
 
     // Ensure expected negative values are negative.
@@ -73,12 +71,7 @@ define('mojo/apps/js/test/js_to_cpp_unittest', [
       writeDataPipe(dataPipe1, senderData);
       writeDataPipe(dataPipe2, senderData);
 
-      resultList = new jsToCpp.EchoArgsList();
-      resultList.next = new jsToCpp.EchoArgsList();
-      resultList.item = specialArg;
-      resultList.next.item = arg;
-
-      this.cppSide_.echoResponse(resultList);
+      this.cppSide_.echoResponse(createEchoArgsList(specialArg, arg));
 
       core.close(dataPipe1.producerHandle);
       core.close(dataPipe2.producerHandle);
@@ -92,8 +85,9 @@ define('mojo/apps/js/test/js_to_cpp_unittest', [
     var iteration = 0;
     var dataPipe;
     var messagePipe;
-    var stopSignalled = false;
     var proto = connector.Connector.prototype;
+    var resultList;
+    var stopSignalled = false;
 
     proto.realAccept = proto.accept;
     proto.accept = function (message) {
@@ -116,7 +110,46 @@ define('mojo/apps/js/test/js_to_cpp_unittest', [
       writeDataPipe(dataPipe, senderData);
       arg.data_handle = dataPipe.consumerHandle;
       arg.message_handle = messagePipe.handle1;
-      this.cppSide_.bitFlipResponse(arg);
+      resultList = createEchoArgsList(arg);
+      this.cppSide_.bitFlipResponse(resultList);
+      core.close(dataPipe.producerHandle);
+      core.close(messagePipe.handle0);
+      iteration += 1;
+    }
+
+    proto.accept = proto.realAccept;
+    proto.realAccept = null;
+    this.cppSide_.testFinished();
+  };
+
+  JsSideConnection.prototype.backPointer = function (arg) {
+    var iteration = 0;
+    var dataPipe;
+    var messagePipe;
+    var proto = connector.Connector.prototype;
+    var resultList = createEchoArgsList(arg);
+    var stopSignalled = false;
+
+    proto.realAccept = proto.accept;
+    proto.accept = function (message) {
+      var delta = 8 * (1 + iteration % 32);
+      var offset = 8 * ((iteration / 32) | 0);
+      if (offset < message.buffer.arrayBuffer.byteLength - 4) {
+        message.buffer.dataView.setUint32(offset, 0x100000000 - delta, true);
+        message.buffer.dataView.setUint32(offset + 4, 0xffffffff, true);
+        return this.realAccept(message);
+      }
+      stopSignalled = true;
+      return false;
+    };
+
+    while (!stopSignalled) {
+      dataPipe = core.createDataPipe(DATA_PIPE_PARAMS);
+      messagePipe = core.createMessagePipe();
+      writeDataPipe(dataPipe, senderData);
+      arg.data_handle = dataPipe.consumerHandle;
+      arg.message_handle = messagePipe.handle1;
+      this.cppSide_.backPointerResponse(resultList);
       core.close(dataPipe.producerHandle);
       core.close(messagePipe.handle0);
       iteration += 1;
@@ -142,6 +175,20 @@ define('mojo/apps/js/test/js_to_cpp_unittest', [
     return true;
   }
 
+  function createEchoArgsListElement(item, next) {
+    var list = new jsToCpp.EchoArgsList();
+    list.item = item;
+    list.next = next;
+    return list;
+  }
+
+  function createEchoArgsList() {
+    var genuineArray = Array.prototype.slice.call(arguments);
+    return genuineArray.reduceRight(function (previous, current) {
+      return createEchoArgsListElement(current, previous);
+    }, null);
+  }
+
   return function(handle) {
     var i;
     senderData = new Uint8Array(DATA_PIPE_PARAMS.capacityNumBytes);