Add --no-merges to roll_dep.py

roll_dep.py

Index: roll_dep.py
diff --git a/roll_dep.py b/roll_dep.py
index 9097b832176dc8df357ef939ad1b7803fc2c7959..cead95dcb163bc7ac1424a0940c8de1f3c478028 100755
--- a/roll_dep.py
+++ b/roll_dep.py
@@ -115,8 +115,11 @@ def roll(root, deps_dir, roll_to, key, reviewers, bug, no_log, log_limit):
   upstream_url = check_output(
       ['git', 'config', 'remote.origin.url'], cwd=full_dir).strip()
   log_url = get_log_url(upstream_url, head, roll_to)
+  cmd = [
+    'git', 'log', commit_range, '--date=short', '--no-merges',
+  ]
   logs = check_output(
-      ['git', 'log', commit_range, '--date=short', '--format=%ad %ae %s'],
+      cmd + ['--format=%ad %ae %s'], # Args with '=' are automatically quoted.

[Johann, 2015/10/07 18:20:11]

so this is kind of messy because for --arg=<string> check_output automatically
quotes <string>. if it's quoted in the cmd definition above, then the output
looks like this:
'2015-10-01 marpan@chromium.org Add first_spatial_layer_to_encode to SVC.'

with the extra '' around the entire string (and breaking the regex below to
strip the @ part of the email)

[M-A Ruel, 2015/10/07 18:43:11]

IIRC, it works with "" but not ''. Please confirm.

       cwd=full_dir)
   logs = re.sub(r'(?m)^(\d\d\d\d-\d\d-\d\d [^@]+)@[^ ]+( .*)$', r'\1\2', logs)

[Johann, 2015/10/07 18:20:11]

a potential fix is to rework the regex to remove the outside quotes in addition
to stripping the @ part of the email.

   nb_commits = logs.count('\n')
@@ -130,8 +133,8 @@ def roll(root, deps_dir, roll_to, key, reviewers, bug, no_log, log_limit):
   log_section = ''
   if log_url:
     log_section = log_url + '\n\n'
-  log_section += '$ git log %s --date=short --format=\'%%ad %%ae %%s\'\n' % (
-      commit_range)
+  log_section += '$ %s ' % ' '.join(cmd)
+  log_section += '--format=\'%ad %ae %s\'\n'

[Johann, 2015/10/07 18:20:11]

without the quotes above, the command printed is $ git log 7d28d12ef..ce3f4ade6
--date=short --no-merges --format=%ad %ae %s

and copy-pasting it breaks before the --format= string is not quoted.

   if not no_log and should_show_log(upstream_url):
     if logs.count('\n') > log_limit:
       # Keep the first N log entries.