Avoid computing patch_root in get_files_affected_by_patch.

recipe_modules/gclient/api.py

Index: recipe_modules/gclient/api.py
diff --git a/recipe_modules/gclient/api.py b/recipe_modules/gclient/api.py
index 6b44dab1d2bce72726b22b6552ef11de1abea020..f858b0231c33a28660779d5a9d621890ec1c3798 100644
--- a/recipe_modules/gclient/api.py
+++ b/recipe_modules/gclient/api.py
@@ -376,3 +376,23 @@ class GclientApi(recipe_api.RecipeApi):
     path, revision = cfg.patch_projects.get(patch_project, (None, None))
     if path and revision and path not in cfg.revisions:
       cfg.revisions[path] = revision
+
+  def get_files_affected_by_patch(self, patch_project, gclient_config=None):
+    """Returns list of paths to files affected by the patch."""
+    patch_root = self.calculate_patch_root(patch_project, gclient_config)

[Michael Achenbach, 2016/04/29 14:11:53]

Maybe patch_root should be a parameter to this method instead of patch_project,
gclient_config. Then the patch_root should be calculated elsewhere, using the
method from gclient.

[tandrii(chromium), 2016/04/29 15:09:41]

Good idea. Will do that.

+    step_result = self.m.git('diff', '--cached', '--name-only',
+                             cwd=self.m.path['root'].join(patch_root),
+                             name='git diff to analyze patch',
+                             stdout=self.m.raw_io.output(),
+                             step_test_data=lambda:
+                               self.m.raw_io.test_api.stream_output('foo.cc'))
+    paths = step_result.stdout.split()
+    if patch_root:
+      paths = [self.m.path.join(patch_root, path) for path in paths]
+    if self.m.platform.is_win:
+      # Looks like "analyze" wants POSIX slashes even on Windows (since git
+      # uses that format even on Windows).
+      paths = [path.replace('\\', '/') for path in paths]
+
+    step_result.presentation.logs['files'] = paths
+    return paths