Better handling of the color git configuration

If the user specified auto in the color configuration the script has to be
smart where it should force the colors out. If the user chose always as
the color configuration the scripts has to be smart were it forces the
colors out.

- Considers color configuration when printing git log
- Fix branch name parsing when the color configuration was set to
  'always'

Change-Id: Iaada6ab3265418f547350777f358e6a1794913a3

git-review

@@ -194,12 +194,18 @@ def parse_git_show(remote, verb):
     return (hostname, team, username, port, project_name)
 
 
+def git_config_get_value(section, option):
+    cmd = "git config --get %s.%s" % (section, option)
+    return run_command(cmd).strip()
+
+
 def check_remote(remote):
     """Check that a Gerrit Git remote repo exists, if not, set one."""
 
     if remote in run_command("git remote").split("\n"):
 
-        for current_remote in run_command("git branch -a").split("\n"):
+        remotes = run_command("git branch -a --color=never").split("\n")
+        for current_remote in remotes:
             if current_remote.strip() == "remotes/%s/master" % (remote) \
                 and not UPDATE:
                 return
@@ -266,7 +272,7 @@ def get_branch_name(target_branch):
     if _branch_name is not None:
         return _branch_name
     _branch_name = None
-    for branch in run_command("git branch").split("\n"):
+    for branch in run_command("git branch --color=never").split("\n"):
         if branch.startswith('*'):
             _branch_name = branch.split()[1].strip()
     if _branch_name == "(no":
@@ -275,10 +281,15 @@ def get_branch_name(target_branch):
 
 
 def assert_one_change(remote, branch, yes):
-
     branch_name = get_branch_name(branch)
-    cmd = "git log --oneline %s --not remotes/%s/%s" % (branch_name,
-                                                        remote, branch)
+    color = git_config_get_value("color", "ui")
+    if color == "":
+        color = "auto"
+    elif color == "auto":
+        # Python is not a tty, we have to force colors
+        color = "always"
+    cmd = "git log --color=%s --oneline %s --not remotes/%s/%s" % (color,
+                                              branch_name, remote, branch)
     (status, output) = run_command_status(cmd)
     if status != 0:
         print "Had trouble running %s" % cmd