If we're running in nohooks mode, don't bother to accumulate file_list in gclient.

This enables significant time savings, especially since file_list only exists to
enable file-specific hooks (which, AFAIK, nothing actually uses). On a z620
(linux) using the cached git repos, a first-time `gclient sync --nohooks` takes:
  * (with)    131.06s user 14.10s  system 117% cpu 2:03.89 total
  * (without) 482.13s user 189.35s system 144% cpu 7:45.63 total

This change makes nohooks cause file_list to be None if we don't need to
accumulate it, and updates GitWrapper and SvnWrapper appropriately.

R=szager@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/18541006

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@210026 0039d316-1c4b-4281-b951-d872f2087c98

gclient.py

@@ -591,7 +591,7 @@ class Dependency(gclient_utils.WorkItem, DependencySettings):
     # copy state, so skip the SCM status check.
     run_scm = command not in ('runhooks', 'recurse', None)
     parsed_url = self.LateOverride(self.url)
-    file_list = []
+    file_list = [] if not options.nohooks else None
     if run_scm and parsed_url:
       if isinstance(parsed_url, self.FileImpl):
         # Special support for single-file checkout.
@@ -612,11 +612,12 @@ class Dependency(gclient_utils.WorkItem, DependencySettings):
         self._used_scm = gclient_scm.CreateSCM(
             parsed_url, self.root.root_dir, self.name)
         self._used_scm.RunCommand(command, options, args, file_list)
+        if file_list:
           file_list = [os.path.join(self.name, f.strip()) for f in file_list]
 
       # TODO(phajdan.jr): We should know exactly when the paths are absolute.
       # Convert all absolute paths to relative.
-      for i in range(len(file_list)):
+      for i in range(len(file_list or [])):
         # It depends on the command being executed (like runhooks vs sync).
         if not os.path.isabs(file_list[i]):
           continue
@@ -630,7 +631,7 @@ class Dependency(gclient_utils.WorkItem, DependencySettings):
     # Always parse the DEPS file.
     self.ParseDepsFile()
 
-    self._run_is_done(file_list, parsed_url)
+    self._run_is_done(file_list or [], parsed_url)
 
     if self.recursion_limit:
       # Parse the dependencies of this dependency.

gclient_scm.py

@@ -137,10 +137,6 @@ class SCMWrapper(object):
       self.checkout_path = os.path.join(self._root_dir, self.relpath)
 
   def RunCommand(self, command, options, args, file_list=None):
-    # file_list will have all files that are modified appended to it.
-    if file_list is None:
-      file_list = []
-
     commands = ['cleanup', 'update', 'updatesingle', 'revert',
                 'revinfo', 'status', 'diff', 'pack', 'runhooks']
 
@@ -220,7 +216,7 @@ class GitWrapper(SCMWrapper):
   def GetCheckoutRoot(self):
     return scm.GIT.GetCheckoutRoot(self.checkout_path)
 
-  def GetRevisionDate(self, revision):
+  def GetRevisionDate(self, _revision):
     """Returns the given revision's date in ISO-8601 format (which contains the
     time zone)."""
     # TODO(floitsch): get the time-stamp of the given revision and not just the
@@ -234,11 +230,11 @@ class GitWrapper(SCMWrapper):
     There's no real git equivalent for the svn cleanup command, do a no-op.
     """
 
-  def diff(self, options, args, file_list):
+  def diff(self, options, _args, _file_list):
     merge_base = self._Capture(['merge-base', 'HEAD', 'origin'])
     self._Run(['diff', merge_base], options)
 
-  def pack(self, options, args, file_list):
+  def pack(self, _options, _args, _file_list):
     """Generates a patch file which can be applied to the root of the
     repository.
 
@@ -293,6 +289,7 @@ class GitWrapper(SCMWrapper):
     self._Run(fetch_cmd + quiet, options)
     self._Run(['reset', '--hard', revision] + quiet, options)
     self.UpdateSubmoduleConfig()
+    if file_list is not None:
       files = self._Capture(['ls-files']).splitlines()
       file_list.extend([os.path.join(self.checkout_path, f) for f in files])
 
@@ -332,7 +329,7 @@ class GitWrapper(SCMWrapper):
         revision = default_rev
 
     rev_str = ' at %s' % revision
-    files = []
+    files = [] if file_list is not None else None
 
     printed_path = False
     verbose = []
@@ -359,6 +356,7 @@ class GitWrapper(SCMWrapper):
       gclient_utils.safe_makedirs(os.path.dirname(self.checkout_path))
       self._Clone(revision, url, options)
       self.UpdateSubmoduleConfig()
+      if file_list is not None:
         files = self._Capture(['ls-files']).splitlines()
         file_list.extend([os.path.join(self.checkout_path, f) for f in files])
       if not verbose:
@@ -510,6 +508,7 @@ class GitWrapper(SCMWrapper):
       raise gclient_utils.Error(switch_error)
     else:
       # case 3 - the default case
+      if files is not None:
         files = self._Capture(['diff', upstream_branch, '--name-only']).split()
       if verbose:
         print('Trying fast-forward merge to branch : %s' % upstream_branch)
@@ -572,6 +571,7 @@ class GitWrapper(SCMWrapper):
             print('')
 
     self.UpdateSubmoduleConfig()
+    if file_list is not None:
       file_list.extend([os.path.join(self.checkout_path, f) for f in files])
 
     # If the rebase generated a conflict, abort and ask user to fix
@@ -601,7 +601,7 @@ class GitWrapper(SCMWrapper):
           gclient_utils.rmtree(full_path)
 
 
-  def revert(self, options, args, file_list):
+  def revert(self, options, _args, file_list):
     """Reverts local modifications.
 
     All reverted files will be appended to file_list.
@@ -624,19 +624,23 @@ class GitWrapper(SCMWrapper):
     if deps_revision.startswith('refs/heads/'):
       deps_revision = deps_revision.replace('refs/heads/', 'origin/')
 
+    if file_list is not None:
       files = self._Capture(['diff', deps_revision, '--name-only']).split()
+
     self._Run(['reset', '--hard', deps_revision], options)
     self._Run(['clean', '-f', '-d'], options)
+
+    if file_list is not None:
       file_list.extend([os.path.join(self.checkout_path, f) for f in files])
 
-  def revinfo(self, options, args, file_list):
+  def revinfo(self, _options, _args, _file_list):
     """Returns revision"""
     return self._Capture(['rev-parse', 'HEAD'])
 
   def runhooks(self, options, args, file_list):
     self.status(options, args, file_list)
 
-  def status(self, options, args, file_list):
+  def status(self, options, _args, file_list):
     """Display status information."""
     if not os.path.isdir(self.checkout_path):
       print(('\n________ couldn\'t run status in %s:\n'
@@ -644,6 +648,7 @@ class GitWrapper(SCMWrapper):
     else:
       merge_base = self._Capture(['merge-base', 'HEAD', 'origin'])
       self._Run(['diff', '--name-status', merge_base], options)
+      if file_list is not None:
         files = self._Capture(['diff', '--name-only', merge_base]).split()
         file_list.extend([os.path.join(self.checkout_path, f) for f in files])
 
@@ -830,6 +835,7 @@ class GitWrapper(SCMWrapper):
   def _AttemptRebase(self, upstream, files, options, newbase=None,
                      branch=None, printed_path=False):
     """Attempt to rebase onto either upstream or, if specified, newbase."""
+    if files is not None:
       files.extend(self._Capture(['diff', upstream, '--name-only']).split())
     revision = upstream
     if newbase:
@@ -955,7 +961,7 @@ class GitWrapper(SCMWrapper):
                                 '\tPlease commit, stash, or reset.\n'
                                   % (self.relpath, rev_str))
 
-  def _CheckDetachedHead(self, rev_str, options):
+  def _CheckDetachedHead(self, rev_str, _options):
     # HEAD is detached. Make sure it is safe to move away from (i.e., it is
     # reference by a commit). If not, error out -- most likely a rebase is
     # in progress, try to detect so we can give a better error.
@@ -1057,18 +1063,18 @@ class SVNWrapper(SCMWrapper):
         os.path.join(self.checkout_path, '.'))
     return date.strip()
 
-  def cleanup(self, options, args, file_list):
+  def cleanup(self, options, args, _file_list):
     """Cleanup working copy."""
     self._Run(['cleanup'] + args, options)
 
-  def diff(self, options, args, file_list):
+  def diff(self, options, args, _file_list):
     # NOTE: This function does not currently modify file_list.
     if not os.path.isdir(self.checkout_path):
       raise gclient_utils.Error('Directory %s is not present.' %
           self.checkout_path)
     self._Run(['diff'] + args, options)
 
-  def pack(self, options, args, file_list):
+  def pack(self, _options, args, _file_list):
     """Generates a patch file which can be applied to the root of the
     repository."""
     if not os.path.isdir(self.checkout_path):
@@ -1286,7 +1292,7 @@ class SVNWrapper(SCMWrapper):
           options.revision)
       self._Run(command, options, cwd=self._root_dir)
 
-  def revert(self, options, args, file_list):
+  def revert(self, options, _args, file_list):
     """Reverts local modifications. Subversion specific.
 
     All reverted files will be appended to file_list, even if Subversion
@@ -1318,6 +1324,7 @@ class SVNWrapper(SCMWrapper):
       return self.update(options, [], file_list)
 
     def printcb(file_status):
+      if file_list is not None:
         file_list.append(file_status[1])
       if logging.getLogger().isEnabledFor(logging.INFO):
         logging.info('%s%s' % (file_status[0], file_status[1]))
@@ -1340,7 +1347,7 @@ class SVNWrapper(SCMWrapper):
       # Maybe the directory disapeared meanwhile. Do not throw an exception.
       logging.error('Failed to update:\n%s' % str(e))
 
-  def revinfo(self, options, args, file_list):
+  def revinfo(self, _options, _args, _file_list):
     """Display revision"""
     try:
       return scm.SVN.CaptureRevision(self.checkout_path)
@@ -1362,7 +1369,7 @@ class SVNWrapper(SCMWrapper):
     else:
       self._RunAndGetFileList(command, options, file_list)
 
-  def GetUsableRev(self, rev, options):
+  def GetUsableRev(self, rev, _options):
     """Verifies the validity of the revision for this repository."""
     if not scm.SVN.IsValidRevision(url='%s@%s' % (self.url, rev)):
       raise gclient_utils.Error(

scm.py

@@ -512,6 +512,9 @@ class SVN(object):
       Error: An error occurred while running the svn command.
     """
     stdout = stdout or sys.stdout
+    if file_list is None:
+      # Even if our caller doesn't care about file_list, we use it internally.
+      file_list = []
 
     # svn update and svn checkout use the same pattern: the first three columns
     # are for file status, property status, and lock status.  This is followed