Fix for initial or detached status branch info

Author: wkentaro

gitstatus.py

@@ -5,9 +5,22 @@
 prehash = ':'
 
 import sys
+import re
+import subprocess
 from subprocess import Popen, PIPE
 
 
+def get_detached_status_name():
+    cmd = ['git', 'describe', '--all']
+    output = subprocess.check_output(cmd).strip()
+    tag_hash = output.split('-g')
+    if len(tag_hash) == 1:
+        return tag_hash[0]  # tag
+    elif len(tag_hash) == 2:
+        return tag_hash[1]  # hash
+    return output  # unexpected status
+
+
 # `git status --porcelain -b` can collect all information
 # branch, remote_branch, untracked, staged, changed, conflicts, ahead, behind
 po = Popen(['git', 'status', '--porcelain', '-b'], stdout=PIPE, stderr=PIPE)
@@ -21,8 +34,12 @@
 status = [(line[0], line[1], line[2:]) for line in stdout.decode('utf-8').splitlines()]
 for st in status:
     if st[0] == '#' and st[1] == '#':
-        if len(st[2].strip().split('...')) == 1:
+        if re.search('Initial commit on', st[2]):
+            branch = st[2].split(' ')[-1]
+        elif len(st[2].strip().split('...')) == 1:
             branch = st[2].strip()
+            if branch == 'HEAD (no branch)':
+                branch = get_detached_status_name()
         else:
             # current and remote branch info
             branch, rest = st[2].strip().split('...')