Revert of Allow MojoAsyncResourceHandler::OnWillRead to complete asyncronously

content/browser/loader/mojo_async_resource_handler_unittest.cc

Index: content/browser/loader/mojo_async_resource_handler_unittest.cc
diff --git a/content/browser/loader/mojo_async_resource_handler_unittest.cc b/content/browser/loader/mojo_async_resource_handler_unittest.cc
index 46c4cf05e278d5d7288fccdd2830dcfc85d56581..2a29d61f35740c778053c7a7be643e7cb5bccd49 100644
--- a/content/browser/loader/mojo_async_resource_handler_unittest.cc
+++ b/content/browser/loader/mojo_async_resource_handler_unittest.cc
@@ -585,7 +585,8 @@
     contents.append(buffer, read_size);
   }
   EXPECT_EQ(data, contents);
-  EXPECT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->status());
+  EXPECT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
+            mock_loader_->status());
 }
 
 TEST_F(MojoAsyncResourceHandlerTest,
@@ -722,10 +723,8 @@
 
   ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
   std::string data(mock_loader_->io_buffer_size(), 'a');
-  ASSERT_EQ(MockResourceLoader::Status::IDLE,
+  ASSERT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
             mock_loader_->OnReadCompleted(data));
-  ASSERT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
-            mock_loader_->OnWillRead());
   url_loader_client_.RunUntilResponseBodyArrived();
   ASSERT_TRUE(url_loader_client_.response_body().is_valid());
 
@@ -765,122 +764,45 @@
 
 TEST_F(MojoAsyncResourceHandlerTest, BeginWriteReturnsShouldWaitOnWillRead) {
   handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
-
-  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
-  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
-
-  // Bytes are read one-at-a-time, and each OnWillRead() call completes
-  // asynchronously. Note that this loop runs 4 times (once for the terminal
-  // '\0').
-  const char kReadData[] = "ABC";
-  for (const char read_char : kReadData) {
-    handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
-    ASSERT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
-              mock_loader_->OnWillRead());
-    EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
-
-    handler_->ResetBeginWriteExpectation();
-    handler_->OnWritableForTesting();
-    EXPECT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->status());
-
-    ASSERT_EQ(MockResourceLoader::Status::IDLE,
-              mock_loader_->OnReadCompleted(std::string(1, read_char)));
-    url_loader_client_.RunUntilResponseBodyArrived();
-
-    // Keep on trying to read the data until it succeeds.
-    while (true) {
-      char buffer[16];
-      uint32_t read_size = sizeof(buffer);
-      MojoResult result =
-          mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
-                            &read_size, MOJO_READ_DATA_FLAG_NONE);
-      if (result != MOJO_RESULT_SHOULD_WAIT) {
-        ASSERT_EQ(MOJO_RESULT_OK, result);
-        ASSERT_EQ(1u, read_size);
-        EXPECT_EQ(read_char, buffer[0]);
-        break;
-      }
-
-      base::RunLoop().RunUntilIdle();
-    }
-  }
-
-  // Should only count as one in-flight request.
-  EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
-
-  ASSERT_EQ(MockResourceLoader::Status::IDLE,
-            mock_loader_->OnResponseCompleted(
-                net::URLRequestStatus::FromError(net::OK)));
-
-  url_loader_client_.RunUntilComplete();
-  EXPECT_TRUE(url_loader_client_.has_received_completion());
-
-  handler_.reset();
-  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
-}
-
-// Same as above, but after the first OnWriteable() call, BeginWrite() indicates
-// should wait again. Unclear if this can happen in practice, but seems best to
-// support it.
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
+}
+
 TEST_F(MojoAsyncResourceHandlerTest,
-       BeginWriteReturnsShouldWaitTwiceOnWillRead) {
+       BeginWriteReturnsShouldWaitOnWillReadAndThenReturnsOK) {
   handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
-
-  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
-  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
-
-  // Bytes are read one-at-a-time, and each OnWillRead() call completes
-  // asynchronously. Note that this loop runs 4 times (once for the terminal
-  // '\0').
-  const char kReadData[] = "ABC";
-  for (const char read_char : kReadData) {
-    handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
-    ASSERT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
-              mock_loader_->OnWillRead());
-    EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
-
-    handler_->OnWritableForTesting();
-    EXPECT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
-              mock_loader_->status());
-
-    handler_->ResetBeginWriteExpectation();
-    handler_->OnWritableForTesting();
-    EXPECT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->status());
-
-    ASSERT_EQ(MockResourceLoader::Status::IDLE,
-              mock_loader_->OnReadCompleted(std::string(1, read_char)));
-    url_loader_client_.RunUntilResponseBodyArrived();
-
-    // Keep on trying to read the data until it succeeds.
-    while (true) {
-      char buffer[16];
-      uint32_t read_size = sizeof(buffer);
-      MojoResult result =
-          mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
-                            &read_size, MOJO_READ_DATA_FLAG_NONE);
-      if (result != MOJO_RESULT_SHOULD_WAIT) {
-        ASSERT_EQ(MOJO_RESULT_OK, result);
-        ASSERT_EQ(1u, read_size);
-        EXPECT_EQ(read_char, buffer[0]);
-        break;
-      }
-
-      base::RunLoop().RunUntilIdle();
-    }
-  }
-
-  // Should only count as one in-flight request.
-  EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
-
-  ASSERT_EQ(MockResourceLoader::Status::IDLE,
-            mock_loader_->OnResponseCompleted(
-                net::URLRequestStatus::FromError(net::OK)));
-
-  url_loader_client_.RunUntilComplete();
-  EXPECT_TRUE(url_loader_client_.has_received_completion());
-
-  handler_.reset();
-  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  size_t written = 0;
+  while (true) {
+    ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
+    MockResourceLoader::Status result = mock_loader_->OnReadCompleted(
+        std::string(mock_loader_->io_buffer_size(), 'X'));
+    written += mock_loader_->io_buffer_size();
+    if (result == MockResourceLoader::Status::CALLBACK_PENDING)
+      break;
+    ASSERT_EQ(MockResourceLoader::Status::IDLE, result);
+  }
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+  handler_->ResetBeginWriteExpectation();
+  handler_->OnWritableForTesting();
+
+  std::string actual;
+  while (actual.size() < written) {
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    ASSERT_TRUE(result == MOJO_RESULT_OK || result == MOJO_RESULT_SHOULD_WAIT);
+    if (result == MOJO_RESULT_OK)
+      actual.append(buf, read_size);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_EQ(std::string(written, 'X'), actual);
+  EXPECT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->status());
 }
 
 TEST_F(MojoAsyncResourceHandlerTest,
@@ -947,7 +869,7 @@
   mock_loader_->WaitUntilIdleOrCanceled();
   EXPECT_FALSE(url_loader_client_.has_received_completion());
   EXPECT_EQ(MockResourceLoader::Status::CANCELED, mock_loader_->status());
-  EXPECT_EQ(net::ERR_INSUFFICIENT_RESOURCES, mock_loader_->error_code());
+  EXPECT_EQ(net::ERR_FAILED, mock_loader_->error_code());
 }
 
 TEST_F(MojoAsyncResourceHandlerUploadTest, UploadProgressHandling) {
@@ -1020,10 +942,12 @@
 TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
        OnWillReadWithLongContents) {
   ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
-
+  ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
   std::string expected;
   for (int i = 0; i < 3 * mock_loader_->io_buffer_size() + 2; ++i)
     expected += ('A' + i % 26);
+
+  ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnReadCompleted(0));
 
   size_t written = 0;
   std::string actual;
@@ -1031,7 +955,7 @@
     while (written < expected.size() &&
            mock_loader_->status() == MockResourceLoader::Status::IDLE) {
       ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
-      size_t to_be_written =
+      const size_t to_be_written =
           std::min(static_cast<size_t>(mock_loader_->io_buffer_size()),
                    expected.size() - written);
 
@@ -1069,16 +993,10 @@
   ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
   ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
 
-  // Whether the next OnReadCompleted call or OnWillRead returns the error
-  // depends on whether or not an intermediary buffer is being used by the
-  // MojoAsyncResourceHandler.
   handler_->set_begin_write_expectation(MOJO_RESULT_UNKNOWN);
-  MockResourceLoader::Status result = mock_loader_->OnReadCompleted(
-      std::string(mock_loader_->io_buffer_size(), 'A'));
-  if (result == MockResourceLoader::Status::CANCELED)
-    return;
-  ASSERT_EQ(MockResourceLoader::Status::IDLE, result);
-  ASSERT_EQ(MockResourceLoader::Status::CANCELED, mock_loader_->OnWillRead());
+  ASSERT_EQ(MockResourceLoader::Status::CANCELED,
+            mock_loader_->OnReadCompleted(
+                std::string(mock_loader_->io_buffer_size(), 'A')));
 }
 
 TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
@@ -1086,32 +1004,21 @@
   ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
   ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
 
-  // Whether the next OnReadCompleted call or OnWillRead call completes
-  // asynchronously depends on whether or not an intermediary buffer is being
-  // used by the MojoAsyncResourceHandler.
   handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
-  MockResourceLoader::Status result = mock_loader_->OnReadCompleted(
-      std::string(mock_loader_->io_buffer_size() - 1, 'A'));
-  if (result == MockResourceLoader::Status::CALLBACK_PENDING)
-    return;
-
   ASSERT_EQ(MockResourceLoader::Status::CALLBACK_PENDING,
-            mock_loader_->OnWillRead());
+            mock_loader_->OnReadCompleted(
+                std::string(mock_loader_->io_buffer_size(), 'A')));
 }
 
 TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
        BeginWriteFailsOnResume) {
   ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
+  ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnReadCompleted(0));
 
   while (true) {
-    // Whether the next OnReadCompleted call or OnWillRead call completes
-    // asynchronously depends on whether or not an intermediary buffer is being
-    // used by the MojoAsyncResourceHandler.
-    MockResourceLoader::Status result = mock_loader_->OnWillRead();
-    if (result == MockResourceLoader::Status::CALLBACK_PENDING)
-      break;
-    ASSERT_EQ(MockResourceLoader::Status::IDLE, result);
-    result = mock_loader_->OnReadCompleted(
+    ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
+    MockResourceLoader::Status result = mock_loader_->OnReadCompleted(
         std::string(mock_loader_->io_buffer_size(), 'A'));
     if (result == MockResourceLoader::Status::CALLBACK_PENDING)
       break;
@@ -1132,25 +1039,16 @@
     base::RunLoop().RunUntilIdle();
   }
 
-  if (mock_loader_->status() == MockResourceLoader::Status::IDLE)
-    EXPECT_EQ(MockResourceLoader::Status::CANCELED, mock_loader_->OnWillRead());
-
   EXPECT_FALSE(url_loader_client_.has_received_completion());
-  EXPECT_EQ(net::ERR_INSUFFICIENT_RESOURCES, mock_loader_->error_code());
+  EXPECT_EQ(net::ERR_FAILED, mock_loader_->error_code());
 }
 
 TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest, CancelWhileWaiting) {
   ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
 
   while (true) {
-    // Whether the next OnReadCompleted call or OnWillRead call completes
-    // asynchronously depends on whether or not an intermediary buffer is being
-    // used by the MojoAsyncResourceHandler.
-    MockResourceLoader::Status result = mock_loader_->OnWillRead();
-    if (result == MockResourceLoader::Status::CALLBACK_PENDING)
-      break;
-    ASSERT_EQ(MockResourceLoader::Status::IDLE, result);
-    result = mock_loader_->OnReadCompleted(
+    ASSERT_EQ(MockResourceLoader::Status::IDLE, mock_loader_->OnWillRead());
+    MockResourceLoader::Status result = mock_loader_->OnReadCompleted(
         std::string(mock_loader_->io_buffer_size(), 'A'));
     if (result == MockResourceLoader::Status::CALLBACK_PENDING)
       break;