Pull out a base class from DumpAccessibilityTree

content/browser/accessibility/dump_accessibility_browsertest_base.cc

+// 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.
+
+#include "content/browser/accessibility/dump_accessibility_browsertest_base.h"
+
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/path_service.h"
+#include "base/strings/string16.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "content/browser/accessibility/accessibility_tree_formatter.h"
+#include "content/browser/accessibility/browser_accessibility.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+#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/url_constants.h"
+#include "content/public/test/content_browser_test.h"
+#include "content/public/test/content_browser_test_utils.h"
+#include "content/shell/browser/shell.h"
+#include "content/test/accessibility_browser_test_utils.h"
+
+namespace content {
+
+namespace {
+
+const char kCommentToken = '#';
+const char kMarkSkipFile[] = "#<skip";
+const char kMarkEndOfFile[] = "<-- End-of-file -->";
+const char kSignalDiff[] = "*";
+
+}  // namespace
+
+typedef AccessibilityTreeFormatter::Filter Filter;
+
+DumpAccessibilityTestBase::DumpAccessibilityTestBase() {
+}
+
+DumpAccessibilityTestBase::~DumpAccessibilityTestBase() {
+}
+
+base::string16
+DumpAccessibilityTestBase::DumpUnfilteredAccessibilityTreeAsString() {
+  WebContentsImpl* web_contents = static_cast<WebContentsImpl*>(
+      shell()->web_contents());
+  AccessibilityTreeFormatter formatter(
+      web_contents->GetRootBrowserAccessibilityManager()->GetRoot());
+  std::vector<Filter> filters;
+  filters.push_back(Filter(base::ASCIIToUTF16("*"), Filter::ALLOW));
+  formatter.SetFilters(filters);
+  base::string16 ax_tree_dump;
+  formatter.FormatAccessibilityTree(&ax_tree_dump);
+  return ax_tree_dump;
+}
+
+std::vector<int> DumpAccessibilityTestBase::DiffLines(
+    const std::vector<std::string>& expected_lines,
+    const std::vector<std::string>& actual_lines) {
+  int actual_lines_count = actual_lines.size();
+  int expected_lines_count = expected_lines.size();
+  std::vector<int> diff_lines;
+  int i = 0, j = 0;
+  while (i < actual_lines_count && j < expected_lines_count) {
+    if (expected_lines[j].size() == 0 ||
+        expected_lines[j][0] == kCommentToken) {
+      // Skip comment lines and blank lines in expected output.
+      ++j;
+      continue;
+    }
+
+    if (actual_lines[i] != expected_lines[j])
+      diff_lines.push_back(j);
+    ++i;
+    ++j;
+  }
+
+  // Actual file has been fully checked.
+  return diff_lines;
+}
+
+void DumpAccessibilityTestBase::ParseHtmlForExtraDirectives(
+    const std::string& test_html,
+    std::vector<Filter>* filters,
+    std::string* wait_for) {
+  std::vector<std::string> lines;
+  base::SplitString(test_html, '\n', &lines);
+  for (std::vector<std::string>::const_iterator iter = lines.begin();
+       iter != lines.end();
+       ++iter) {
+    const std::string& line = *iter;
+    const std::string& allow_empty_str =
+        AccessibilityTreeFormatter::GetAllowEmptyString();
+    const std::string& allow_str =
+        AccessibilityTreeFormatter::GetAllowString();
+    const std::string& deny_str =
+        AccessibilityTreeFormatter::GetDenyString();
+    const std::string& wait_str = "@WAIT-FOR:";
+    if (StartsWithASCII(line, allow_empty_str, true)) {
+      filters->push_back(
+          Filter(base::UTF8ToUTF16(line.substr(allow_empty_str.size())),
+                 Filter::ALLOW_EMPTY));
+    } else if (StartsWithASCII(line, allow_str, true)) {
+      filters->push_back(Filter(base::UTF8ToUTF16(
+          line.substr(allow_str.size())),
+                                Filter::ALLOW));
+    } else if (StartsWithASCII(line, deny_str, true)) {
+      filters->push_back(Filter(base::UTF8ToUTF16(
+          line.substr(deny_str.size())),
+                                Filter::DENY));
+    } else if (StartsWithASCII(line, wait_str, true)) {
+      *wait_for = line.substr(wait_str.size());
+    }
+  }
+}
+
+void DumpAccessibilityTestBase::RunTest(
+    const base::FilePath::CharType* file_path) {
+  NavigateToURL(shell(), GURL(url::kAboutBlankURL));
+
+  // Setup test paths.
+  base::FilePath dir_test_data;
+  ASSERT_TRUE(PathService::Get(DIR_TEST_DATA, &dir_test_data));
+  base::FilePath test_path(
+      dir_test_data.Append(FILE_PATH_LITERAL("accessibility")));
+  ASSERT_TRUE(base::PathExists(test_path))
+      << test_path.LossyDisplayName();
+
+  base::FilePath html_file = test_path.Append(base::FilePath(file_path));
+  // Output the test path to help anyone who encounters a failure and needs
+  // to know where to look.
+  printf("Testing: %s\n", html_file.MaybeAsASCII().c_str());
+
+  std::string html_contents;
+  base::ReadFileToString(html_file, &html_contents);
+
+  // Read the expected file.
+  std::string expected_contents_raw;
+  base::FilePath expected_file =
+    base::FilePath(html_file.RemoveExtension().value() +
+                   AccessibilityTreeFormatter::GetExpectedFileSuffix());
+  base::ReadFileToString(expected_file, &expected_contents_raw);
+
+  // Tolerate Windows-style line endings (\r\n) in the expected file:
+  // normalize by deleting all \r from the file (if any) to leave only \n.
+  std::string expected_contents;
+  base::RemoveChars(expected_contents_raw, "\r", &expected_contents);
+
+  if (!expected_contents.compare(0, strlen(kMarkSkipFile), kMarkSkipFile)) {
+    printf("Skipping this test on this platform.\n");
+    return;
+  }
+
+  // Parse filters and other directives in the test file.
+  std::string wait_for;
+  AddDefaultFilters(&filters_);
+  ParseHtmlForExtraDirectives(html_contents, &filters_, &wait_for);
+
+  // Load the page.
+  base::string16 html_contents16;
+  html_contents16 = base::UTF8ToUTF16(html_contents);
+  GURL url = GetTestUrl("accessibility",
+                        html_file.BaseName().MaybeAsASCII().c_str());
+
+  // If there's a @WAIT-FOR directive, set up an accessibility notification
+  // waiter that returns on any event; we'll stop when we get the text we're
+  // waiting for, or time out. Otherwise just wait specifically for
+  // the "load complete" event.
+  scoped_ptr<AccessibilityNotificationWaiter> waiter;
+  if (!wait_for.empty()) {
+    waiter.reset(new AccessibilityNotificationWaiter(
+        shell(), AccessibilityModeComplete, ui::AX_EVENT_NONE));
+  } else {
+    waiter.reset(new AccessibilityNotificationWaiter(
+        shell(), AccessibilityModeComplete, ui::AX_EVENT_LOAD_COMPLETE));
+  }
+
+  // Load the test html.
+  NavigateToURL(shell(), url);
+
+  // Wait for notifications. If there's a @WAIT-FOR directive, break when
+  // the text we're waiting for appears in the dump, otherwise break after
+  // the first notification, which will be a load complete.
+  do {
+    waiter->WaitForNotification();
+    if (!wait_for.empty()) {
+      base::string16 tree_dump = DumpUnfilteredAccessibilityTreeAsString();
+      if (base::UTF16ToUTF8(tree_dump).find(wait_for) != std::string::npos)
+        wait_for.clear();
+    }
+  } while (!wait_for.empty());
+
+  // Call the subclass to dump the output.
+  std::vector<std::string> actual_lines = Dump();
+
+  // Perform a diff (or write the initial baseline).
+  std::vector<std::string> expected_lines;
+  Tokenize(expected_contents, "\n", &expected_lines);
+  // Marking the end of the file with a line of text ensures that
+  // file length differences are found.
+  expected_lines.push_back(kMarkEndOfFile);
+  actual_lines.push_back(kMarkEndOfFile);
+  std::string actual_contents = JoinString(actual_lines, "\n");
+
+  std::vector<int> diff_lines = DiffLines(expected_lines, actual_lines);
+  bool is_different = diff_lines.size() > 0;
+  EXPECT_FALSE(is_different);
+  if (is_different) {
+    OnDiffFailed();
+
+    // Mark the expected lines which did not match actual output with a *.
+    printf("* Line Expected\n");
+    printf("- ---- --------\n");
+    for (int line = 0, diff_index = 0;
+         line < static_cast<int>(expected_lines.size());
+         ++line) {
+      bool is_diff = false;
+      if (diff_index < static_cast<int>(diff_lines.size()) &&
+          diff_lines[diff_index] == line) {
+        is_diff = true;
+        ++diff_index;
+      }
+      printf("%1s %4d %s\n", is_diff? kSignalDiff : "", line + 1,
+             expected_lines[line].c_str());
+    }
+    printf("\nActual\n");
+    printf("------\n");
+    printf("%s\n", actual_contents.c_str());
+  }
+
+  if (!base::PathExists(expected_file)) {
+    base::FilePath actual_file =
+        base::FilePath(html_file.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();
+  }
+}
+
+}  // namespace content