1 files changed, 57 insertions, 43 deletions

diff --git a/git-p4.py b/git-p4.py
index 212ef2b..13f1240 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -203,14 +203,16 @@ def p4_has_move_command():
     # assume it failed because @... was invalid changelist
     return True
 
-def system(cmd):
+def system(cmd, ignore_error=False):
     expand = isinstance(cmd,basestring)
     if verbose:
         sys.stderr.write("executing %s\n" % str(cmd))
     retcode = subprocess.call(cmd, shell=expand)
-    if retcode:
+    if retcode and not ignore_error:
         raise CalledProcessError(retcode, cmd)
 
+    return retcode
+
 def p4_system(cmd):
     """Specifically invoke p4 as the system command. """
     real_cmd = p4_build_cmd(cmd)
@@ -553,7 +555,12 @@ def p4Where(depotPath):
     return clientPath
 
 def currentGitBranch():
-    return read_pipe("git name-rev HEAD").split(" ")[1].strip()
+    retcode = system(["git", "symbolic-ref", "-q", "HEAD"], ignore_error=True)
+    if retcode != 0:
+        # on a detached head
+        return None
+    else:
+        return read_pipe(["git", "name-rev", "HEAD"]).split(" ")[1].strip()
 
 def isValidGitDir(path):
     if (os.path.exists(path + "/HEAD")
@@ -1741,44 +1748,47 @@ class P4Submit(Command, P4UserMap):
         #
         # Let the user edit the change description, then submit it.
         #
-        if self.edit_template(fileName):
-            # read the edited message and submit
-            ret = True
-            tmpFile = open(fileName, "rb")
-            message = tmpFile.read()
-            tmpFile.close()
-            if self.isWindows:
-                message = message.replace("\r\n", "\n")
-            submitTemplate = message[:message.index(separatorLine)]
-            p4_write_pipe(['submit', '-i'], submitTemplate)
-
-            if self.preserveUser:
-                if p4User:
-                    # Get last changelist number. Cannot easily get it from
-                    # the submit command output as the output is
-                    # unmarshalled.
-                    changelist = self.lastP4Changelist()
-                    self.modifyChangelistUser(changelist, p4User)
-
-            # The rename/copy happened by applying a patch that created a
-            # new file.  This leaves it writable, which confuses p4.
-            for f in pureRenameCopy:
-                p4_sync(f, "-f")
+        submitted = False
 
-        else:
+        try:
+            if self.edit_template(fileName):
+                # read the edited message and submit
+                tmpFile = open(fileName, "rb")
+                message = tmpFile.read()
+                tmpFile.close()
+                if self.isWindows:
+                    message = message.replace("\r\n", "\n")
+                submitTemplate = message[:message.index(separatorLine)]
+                p4_write_pipe(['submit', '-i'], submitTemplate)
+
+                if self.preserveUser:
+                    if p4User:
+                        # Get last changelist number. Cannot easily get it from
+                        # the submit command output as the output is
+                        # unmarshalled.
+                        changelist = self.lastP4Changelist()
+                        self.modifyChangelistUser(changelist, p4User)
+
+                # The rename/copy happened by applying a patch that created a
+                # new file.  This leaves it writable, which confuses p4.
+                for f in pureRenameCopy:
+                    p4_sync(f, "-f")
+                submitted = True
+
+        finally:
             # skip this patch
-            ret = False
-            print "Submission cancelled, undoing p4 changes."
-            for f in editedFiles:
-                p4_revert(f)
-            for f in filesToAdd:
-                p4_revert(f)
-                os.remove(f)
-            for f in filesToDelete:
-                p4_revert(f)
+            if not submitted:
+                print "Submission cancelled, undoing p4 changes."
+                for f in editedFiles:
+                    p4_revert(f)
+                for f in filesToAdd:
+                    p4_revert(f)
+                    os.remove(f)
+                for f in filesToDelete:
+                    p4_revert(f)
 
         os.remove(fileName)
-        return ret
+        return submitted
 
     # Export git tags as p4 labels. Create a p4 label and then tag
     # with that.
@@ -1854,8 +1864,6 @@ class P4Submit(Command, P4UserMap):
     def run(self, args):
         if len(args) == 0:
             self.master = currentGitBranch()
-            if len(self.master) == 0 or not gitBranchExists("refs/heads/%s" % self.master):
-                die("Detecting current git branch failed!")
         elif len(args) == 1:
             self.master = args[0]
             if not branchExists(self.master):
@@ -1863,9 +1871,10 @@ class P4Submit(Command, P4UserMap):
         else:
             return False
 
-        allowSubmit = gitConfig("git-p4.allowSubmit")
-        if len(allowSubmit) > 0 and not self.master in allowSubmit.split(","):
-            die("%s is not in git-p4.allowSubmit" % self.master)
+        if self.master:
+            allowSubmit = gitConfig("git-p4.allowSubmit")
+            if len(allowSubmit) > 0 and not self.master in allowSubmit.split(","):
+                die("%s is not in git-p4.allowSubmit" % self.master)
 
         [upstream, settings] = findUpstreamBranchPoint()
         self.depotPath = settings['depot-paths'][0]
@@ -1933,7 +1942,12 @@ class P4Submit(Command, P4UserMap):
         self.check()
 
         commits = []
-        for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (self.origin, self.master)]):
+        if self.master:
+            commitish = self.master
+        else:
+            commitish = 'HEAD'
+
+        for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (self.origin, commitish)]):
             commits.append(line.strip())
         commits.reverse()