Expand the unit tests for PathFinder in webkitpy

Bug: 710535
Change-Id: I6ce8350af1f1bad0ef1577b67b927381f1c4842f
Reviewed-on: https://chromium-review.googlesource.com/575031Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Quinten Yearsley <qyearsley@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487482}

third_party/WebKit/Tools/Scripts/webkitpy/common/path_finder.py

@@ -75,32 +75,33 @@ def get_webkitpy_thirdparty_dir():
 
 class PathFinder(object):
 
-    def __init__(self, filesystem):
+    def __init__(self, filesystem, sys_path=None, env_path=None):
         self._filesystem = filesystem
         self._dirsep = filesystem.sep
-        self._sys_path = sys.path
-        self._env_path = os.environ['PATH'].split(os.pathsep)
+        self._sys_path = sys_path or sys.path
+        self._env_path = env_path or os.environ['PATH'].split(os.pathsep)
 
     @memoized
-    def _webkit_base(self):
-        """Returns the absolute path to the top of the WebKit tree.
+    def chromium_base(self):
+        return self._filesystem.dirname(self._filesystem.dirname(self._webkit_base()))
 
-        Raises an AssertionError if the top dir can't be determined.
-        """
-        # TODO(qyearsley): This code somewhat duplicates the code in
-        # git.find_checkout_root().
-        module_path = self._filesystem.abspath(self._filesystem.path_to_module(self.__module__))
+    def layout_tests_dir(self):
+        return self._path_from_webkit_base('LayoutTests')
+
+    def perf_tests_dir(self):
+        return self._path_from_webkit_base('PerformanceTests')
+
+    @memoized
+    def _webkit_base(self):
+        """Returns the absolute path to the top of the Blink directory."""
+        module_path = self._filesystem.path_to_module(self.__module__)
         tools_index = module_path.rfind('Tools')
         assert tools_index != -1, 'could not find location of this checkout from %s' % module_path
         return self._filesystem.normpath(module_path[0:tools_index - 1])
 
-    @memoized
-    def chromium_base(self):
-        return self._filesystem.dirname(self._filesystem.dirname(self._webkit_base()))
-
-    # Do not expose this function in order to make the code robust against
-    # directory structure changes.
     def _path_from_webkit_base(self, *comps):
+        # This function is marked as protected in order to make the code
+        # more robust against directory structure changes.
         return self._filesystem.join(self._webkit_base(), *comps)
 
     def path_from_chromium_base(self, *comps):
@@ -112,21 +113,16 @@ class PathFinder(object):
     def path_from_tools_scripts(self, *comps):
         return self._filesystem.join(self._filesystem.join(self._webkit_base(), 'Tools', 'Scripts'), *comps)
 
-    def layout_tests_dir(self):
-        return self._path_from_webkit_base('LayoutTests')
-
     def path_from_layout_tests(self, *comps):
         return self._filesystem.join(self.layout_tests_dir(), *comps)
 
-    def perf_tests_dir(self):
-        return self._path_from_webkit_base('PerformanceTests')
-
     def layout_test_name(self, file_path):
         """Returns a layout test name, given the path from the repo root.
 
         Note: this appears to not work on Windows; see crbug.com/658795.
         Also, this function duplicates functionality that's in
         Port.relative_test_filename.
+
         TODO(qyearsley): De-duplicate this and Port.relative_test_filename,
         and ensure that it works properly with Windows paths.
 
@@ -145,8 +141,11 @@ class PathFinder(object):
 
     @memoized
     def depot_tools_base(self):
-        # This basically duplicates src/build/find_depot_tools.py without the side effects
-        # (adding the directory to sys.path and importing breakpad).
+        """Returns the path to depot_tools, or None if not found.
+
+        This basically duplicates src/build/find_depot_tools.py without the
+        side effects of adding the directory to sys.path or importing breakpad.
+        """
         return (self._check_paths_for_depot_tools(self._sys_path) or
                 self._check_paths_for_depot_tools(self._env_path) or
                 self._check_upward_for_depot_tools())
@@ -158,6 +157,8 @@ class PathFinder(object):
         return None
 
     def _check_upward_for_depot_tools(self):
+        # TODO(qyearsley): Remove this, since on Chromium developer machines
+        # we generally assume that depot_tools is in PATH.
         fs = self._filesystem
         prev_dir = ''
         current_dir = fs.dirname(self._webkit_base())

third_party/WebKit/Tools/Scripts/webkitpy/common/path_finder_unittest.py

@@ -10,30 +10,63 @@ from webkitpy.common.system.filesystem_mock import MockFileSystem
 
 class TestPathFinder(unittest.TestCase):
 
-    # TODO(qyearsley): Add tests for other methods in PathFinder.
-    # Including tests for cases when the separator character is backslash.
+    def test_chromium_base(self):
+        finder = PathFinder(MockFileSystem())
+        self.assertEqual(finder.chromium_base(), '/mock-checkout')
 
-    def test_layout_test_name(self):
+    def test_path_from_chromium_base(self):
         finder = PathFinder(MockFileSystem())
         self.assertEqual(
-            finder.layout_test_name('third_party/WebKit/LayoutTests/test/name.html'),
-            'test/name.html')
+            finder.path_from_chromium_base('foo', 'bar.baz'),
+            '/mock-checkout/foo/bar.baz')
 
-    def test_layout_test_name_not_in_layout_tests_dir(self):
+    def test_layout_tests_dir(self):
         finder = PathFinder(MockFileSystem())
-        self.assertIsNone(finder.layout_test_name('some/other/path/file.html'))
+        self.assertEqual(
+            finder.layout_tests_dir(),
+            '/mock-checkout/third_party/WebKit/LayoutTests')
 
-    # pylint: disable=protected-access
-    def test_webkit_base(self):
+    def test_layout_tests_dir_with_backslash_sep(self):
+        filesystem = MockFileSystem()
+        filesystem.sep = '\\'
+        filesystem.path_to_module = lambda _: (
+            'C:\\mock-checkout\\third_party\\WebKit\\Tools\\Scripts\\webkitpy\\foo.py')
+        finder = PathFinder(filesystem)
+        self.assertEqual(
+            finder.layout_tests_dir(),
+            'C:\\mock-checkout\\third_party\\WebKit\\LayoutTests')
+
+    def test_perf_tests_dir(self):
         finder = PathFinder(MockFileSystem())
-        self.assertEqual(finder._webkit_base(), '/mock-checkout/third_party/WebKit')
+        self.assertEqual(
+            finder.perf_tests_dir(),
+            '/mock-checkout/third_party/WebKit/PerformanceTests')
 
-    def test_chromium_base(self):
+    def test_path_from_layout_tests(self):
         finder = PathFinder(MockFileSystem())
-        self.assertEqual(finder.chromium_base(), '/mock-checkout')
+        self.assertEqual(
+            finder.path_from_layout_tests('external', 'wpt'),
+            '/mock-checkout/third_party/WebKit/LayoutTests/external/wpt')
 
-    def test_path_from_chromium_base(self):
+    def test_layout_test_name(self):
         finder = PathFinder(MockFileSystem())
         self.assertEqual(
-            finder.path_from_chromium_base('foo', 'bar.baz'),
-            '/mock-checkout/foo/bar.baz')
+            finder.layout_test_name('third_party/WebKit/LayoutTests/test/name.html'),
+            'test/name.html')
+
+    def test_layout_test_name_not_in_layout_tests_dir(self):
+        finder = PathFinder(MockFileSystem())
+        self.assertIsNone(
+            finder.layout_test_name('some/other/path/file.html'))
+
+    def test_depot_tools_base_not_found(self):
+        finder = PathFinder(MockFileSystem(), sys_path=['/foo'], env_path=['/bar'])
+        self.assertIsNone(finder.depot_tools_base())
+
+    def test_depot_tools_base_in_sys_path(self):
+        finder = PathFinder(MockFileSystem(), sys_path=['/foo/bar/depot_tools'], env_path=['/bar'])
+        self.assertEqual(finder.depot_tools_base(), '/foo/bar/depot_tools')
+
+    def test_depot_tools_base_in_env_path(self):
+        finder = PathFinder(MockFileSystem(), sys_path=['/foo'], env_path=['/baz/bin/depot_tools'])
+        self.assertEqual(finder.depot_tools_base(), '/baz/bin/depot_tools')