Don't require expectations file for DumpAccessibility tests.

content/browser/accessibility/dump_accessibility_browsertest_base.cc

Index: content/browser/accessibility/dump_accessibility_browsertest_base.cc
diff --git a/content/browser/accessibility/dump_accessibility_browsertest_base.cc b/content/browser/accessibility/dump_accessibility_browsertest_base.cc
index 60c5af63a0c9026b35f48f939bab2a17eebf1f1f..ae0f07641eecafe79074d353851af222f9663af1 100644
--- a/content/browser/accessibility/dump_accessibility_browsertest_base.cc
+++ b/content/browser/accessibility/dump_accessibility_browsertest_base.cc
@@ -8,6 +8,7 @@
 #include <string>
 #include <vector>
 
+#include "base/command_line.h"
 #include "base/path_service.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
@@ -20,6 +21,7 @@
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_paths.h"
+#include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
@@ -132,7 +134,7 @@ void DumpAccessibilityTestBase::RunTest(
 
   // Output the test path to help anyone who encounters a failure and needs
   // to know where to look.
-  printf("Testing: %s\n", file_path.MaybeAsASCII().c_str());
+  LOG(INFO) << "Testing: " << file_path.LossyDisplayName();

[Charlie Reis, 2015/12/08 22:52:05]

We're generally supposed to use DVLOG, right?
http://www.chromium.org/developers/coding-style#TOC-Logging

I don't feel strongly, though, since it's a test framework and this is intended
to be informational.

[dmazzoni, 2015/12/08 23:22:42]

Yeah, it makes it harder to figure out what happened if the test failed, without
this. This is especially important here because these tests have different
expectations on each platform so we often run a try job and look for failures on
bots, not locally - so DVLOG isn't helpful.

 
   std::string html_contents;
   base::ReadFileToString(file_path, &html_contents);
@@ -140,8 +142,18 @@ void DumpAccessibilityTestBase::RunTest(
   // Read the expected file.
   std::string expected_contents_raw;
   base::FilePath expected_file =
-    base::FilePath(file_path.RemoveExtension().value() +
-                   AccessibilityTreeFormatter::GetExpectedFileSuffix());
+      base::FilePath(file_path.RemoveExtension().value() +
+                     AccessibilityTreeFormatter::GetExpectedFileSuffix());
+  if (!base::PathExists(expected_file)) {
+    LOG(INFO) << "File not found: " << expected_file.LossyDisplayName();
+    LOG(INFO) << "No expectation file present, ignoring test on this platform."
+              << " To run this test anyway, create "
+              << expected_file.LossyDisplayName()
+              << " (it can be blank) and then run content_browsertests "

[Charlie Reis, 2015/12/08 22:52:05]

s/blank/empty/

[dmazzoni, 2015/12/09 22:23:19]

Done.

+              << "with the switch: --"
+              << switches::kGenerateAccessibilityTestExpectations;
+    return;
+  }
   base::ReadFileToString(expected_file, &expected_contents_raw);
 
   // Tolerate Windows-style line endings (\r\n) in the expected file:
@@ -150,7 +162,7 @@ void DumpAccessibilityTestBase::RunTest(
   base::RemoveChars(expected_contents_raw, "\r", &expected_contents);
 
   if (!expected_contents.compare(0, strlen(kMarkSkipFile), kMarkSkipFile)) {
-    printf("Skipping this test on this platform.\n");
+    LOG(INFO) << "Skipping this test on this platform.";
     return;
   }
 
@@ -229,19 +241,15 @@ void DumpAccessibilityTestBase::RunTest(
     printf("\nActual\n");
     printf("------\n");
     printf("%s\n", actual_contents.c_str());
-  }
-
-  if (!base::PathExists(expected_file)) {
-    base::FilePath actual_file =
-        base::FilePath(file_path.RemoveExtension().value() +
-                       AccessibilityTreeFormatter::GetActualFileSuffix());
-
-    EXPECT_TRUE(base::WriteFile(
-        actual_file, actual_contents.c_str(), actual_contents.size()));
-
-    ADD_FAILURE() << "No expectation found. Create it by doing:\n"
-                  << "mv " << actual_file.LossyDisplayName() << " "
-                  << expected_file.LossyDisplayName();
+    fflush(stdout);
+
+    if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+            switches::kGenerateAccessibilityTestExpectations)) {
+      EXPECT_TRUE(base::WriteFile(
+          expected_file, actual_contents.c_str(), actual_contents.size()));
+      LOG(ERROR) << "Wrote expectations to: "

[Charlie Reis, 2015/12/08 22:52:05]

Why ERROR in this case?

[dmazzoni, 2015/12/09 22:23:19]

This only happens if the test failed anyway, so I want to make sure it gets
printed even if someone set a different log level.

+                 << expected_file.LossyDisplayName();
+    }
   }
 }