[bisect] - Parse DEPS file manually if execfile fails.

tools/bisect-perf-regression.py

Index: tools/bisect-perf-regression.py
diff --git a/tools/bisect-perf-regression.py b/tools/bisect-perf-regression.py
index 6b98b4b40dcb34b7b2a7ce3f2b3f10b58fad4743..9359a67f50d2f9eb4bb882512e0c8d8296c24027 100755
--- a/tools/bisect-perf-regression.py
+++ b/tools/bisect-perf-regression.py
@@ -76,7 +76,7 @@ DEPOT_DEPS_NAME = {
     "depends" : None,
     "from" : ['cros', 'android-chrome'],
     'viewvc': 'http://src.chromium.org/viewvc/chrome?view=revision&revision=',
-    'deps_var': None
+    'deps_var': 'chromium_rev'
   },
   'webkit' : {
     "src" : "src/third_party/WebKit",
@@ -1367,23 +1367,22 @@ class BisectPerformanceMetrics(object):
 
     return bleeding_edge_revision
 
-  def Get3rdPartyRevisionsFromCurrentRevision(self, depot, revision):
-    """Parses the DEPS file to determine WebKit/v8/etc... versions.
+  def _ParseRevisionsFromDEPSFile(self, depot):
+    """Parses the local DEPS file to determine blink/skia/v8 revisions which may
+    be needed if the bisect recurses into those depots later.
+
+    Args:
+      depot: Depot being bisected.
 
     Returns:
       A dict in the format {depot:revision} if successful, otherwise None.
     """
-    cwd = os.getcwd()
-    self.ChangeToDepotWorkingDirectory(depot)
-
-    results = {}
-
-    if depot == 'chromium' or depot == 'android-chrome':
+    try:
       locals = {'Var': lambda _: locals["vars"][_],
                 'From': lambda *args: None}
       execfile(bisect_utils.FILE_DEPS_GIT, {}, locals)
-
-      os.chdir(cwd)
+      locals = locals['deps']
+      results = {}
 
       rxp = re.compile(".git@(?P<revision>[a-fA-F0-9]+)")
 
@@ -1394,28 +1393,65 @@ class BisectPerformanceMetrics(object):
 
         if (DEPOT_DEPS_NAME[d]['recurse'] and
             depot in DEPOT_DEPS_NAME[d]['from']):
-          if (locals['deps'].has_key(DEPOT_DEPS_NAME[d]['src']) or
-              locals['deps'].has_key(DEPOT_DEPS_NAME[d]['src_old'])):
-            if locals['deps'].has_key(DEPOT_DEPS_NAME[d]['src']):
-              re_results = rxp.search(locals['deps'][DEPOT_DEPS_NAME[d]['src']])
+          if (locals.has_key(DEPOT_DEPS_NAME[d]['src']) or
+              locals.has_key(DEPOT_DEPS_NAME[d]['src_old'])):
+            if locals.has_key(DEPOT_DEPS_NAME[d]['src']):
+              re_results = rxp.search(locals[DEPOT_DEPS_NAME[d]['src']])
               self.depot_cwd[d] = \
                   os.path.join(self.src_cwd, DEPOT_DEPS_NAME[d]['src'][4:])
-            elif locals['deps'].has_key(DEPOT_DEPS_NAME[d]['src_old']):
+            elif (DEPOT_DEPS_NAME[d].has_key('src_old') and
+                locals.has_key(DEPOT_DEPS_NAME[d]['src_old'])):
               re_results = \
-                  rxp.search(locals['deps'][DEPOT_DEPS_NAME[d]['src_old']])
+                  rxp.search(locals[DEPOT_DEPS_NAME[d]['src_old']])
               self.depot_cwd[d] = \
                   os.path.join(self.src_cwd, DEPOT_DEPS_NAME[d]['src_old'][4:])
 
             if re_results:
               results[d] = re_results.group('revision')
             else:
-              print 'Couldn\'t parse revision for %s.' % d
-              print
-              return None
+              warning_text = ('Couldn\'t parse revision for %s while bisecting '
+                  '%s' % (d, depot))
+              if not warningText in self.warnings:
+                self.warnings.append(warningText)
           else:
             print 'Couldn\'t find %s while parsing .DEPS.git.' % d
             print
             return None
+      return results
+    except ImportError:

[qyearsley, 2014/04/25 16:46:19]

This block (line 1422 to 1439) is a bit dense, and could perhaps be extracted to
be a separate function.

[shatch, 2014/04/25 17:17:14]

Done.

+      # We'll parse the "vars" section of the DEPS file.
+      rxp = re.compile("vars = {(?P<revision>[^}]+)", re.MULTILINE)

[qyearsley, 2014/04/25 16:46:19]

<revision> isn't a very clear name for "everything inside of the curly braces in
the vars section". Maybe vars_body?

[shatch, 2014/04/25 17:17:14]

Done.

+      re_results = rxp.search(ReadStringFromFile(bisect_utils.FILE_DEPS_GIT))
+      locals = {}
+      if re_results:

[qyearsley, 2014/04/25 16:46:19]

To avoid nesting one level here, maybe:

if not re_results:
  return {}
vars_body = re_results.group("revision")
for current_line in vars_body.splitlines():
  ...

[shatch, 2014/04/25 17:17:14]

Done.

+        for current_line in re_results.group("revision").splitlines():
+          try:
+            depot_name = current_line.split("'")[1].split("'")[0]
+            depot_revision = current_line.split(": '")[1].split("'")[0]

[qyearsley, 2014/04/25 16:46:19]

These two lines are particularly hard for me to understand. It may be clearer
with an example of what we're expecting current_line to look like?

[shatch, 2014/04/25 17:17:14]

Done.

+            for current_name, current_data in DEPOT_DEPS_NAME.iteritems():
+              if (current_data.has_key('deps_var') and
+                  current_data['deps_var'] == depot_name):
+                src_name = current_name
+                locals[src_name] = depot_revision
+                break
+          except IndexError:
+            pass
+      return locals
+
+  def Get3rdPartyRevisionsFromCurrentRevision(self, depot, revision):
+    """Parses the DEPS file to determine WebKit/v8/etc... versions.
+
+    Returns:
+      A dict in the format {depot:revision} if successful, otherwise None.
+    """
+    cwd = os.getcwd()
+    self.ChangeToDepotWorkingDirectory(depot)
+
+    results = {}
+
+    if depot == 'chromium' or depot == 'android-chrome':
+      results = self._ParseRevisionsFromDEPSFile(depot)
+      os.chdir(cwd)
     elif depot == 'cros':
       cmd = [CROS_SDK_PATH, '--', 'portageq-%s' % self.opts.cros_board,
              'best_visible', '/build/%s' % self.opts.cros_board, 'ebuild',