patman: Allow creating patches for another branch

Add a -b option to allow patches to be created from a branch other than
the current one.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/patman/control.py

@@ -20,7 +20,7 @@ def setup():
     """Do required setup before doing anything"""
     gitutil.Setup()
 
-def prepare_patches(col, count, start, ignore_binary):
+def prepare_patches(col, branch, count, start, ignore_binary):
     """Figure out what patches to generate, then generate them
 
     The patch files are written to the current directory, e.g. 0001_xxx.patch
@@ -28,6 +28,7 @@ def prepare_patches(col, count, start, ignore_binary):
 
     Args:
         col (terminal.Color): Colour output object
+        branch (str): Branch to create patches from (None = current)
         count (int): Number of patches to produce, or -1 to produce patches for
             the current branch back to the upstream commit
         start (int): Start partch to use (0=first / top of branch)
@@ -42,7 +43,7 @@ def prepare_patches(col, count, start, ignore_binary):
     """
     if count == -1:
         # Work out how many patches to send if we can
-        count = (gitutil.CountCommitsToBranch() - start)
+        count = (gitutil.CountCommitsToBranch(branch) - start)
 
     if not count:
         sys.exit(col.Color(col.RED,
@@ -50,9 +51,9 @@ def prepare_patches(col, count, start, ignore_binary):
 
     # Read the metadata from the commits
     to_do = count
-    series = patchstream.GetMetaData(start, to_do)
+    series = patchstream.GetMetaData(branch, start, to_do)
     cover_fname, patch_files = gitutil.CreatePatches(
-        start, to_do, ignore_binary, series)
+        branch, start, to_do, ignore_binary, series)
 
     # Fix up the patch files to our liking, and insert the cover letter
     patchstream.FixPatches(series, patch_files)
@@ -158,9 +159,11 @@ def send(options):
     setup()
     col = terminal.Color()
     series, cover_fname, patch_files = prepare_patches(
-        col, options.count, options.start, options.ignore_binary)
+        col, options.branch, options.count, options.start,
+        options.ignore_binary)
     ok = check_patches(series, patch_files, options.check_patch,
                        options.verbose)
+
     its_a_go = ok or options.ignore_errors
     if its_a_go:
         email_patches(

tools/patman/func_test.py

@@ -426,12 +426,21 @@ complicated as possible''')
             os.chdir(self.gitdir)
 
             # Check that it can detect the current branch
-            self.assertEqual(2, gitutil.CountCommitsToBranch())
+            self.assertEqual(2, gitutil.CountCommitsToBranch(None))
             col = terminal.Color()
             with capture_sys_output() as _:
                 _, cover_fname, patch_files = control.prepare_patches(
-                    col, count=-1, start=0, ignore_binary=False)
+                    col, branch=None, count=-1, start=0, ignore_binary=False)
             self.assertIsNone(cover_fname)
             self.assertEqual(2, len(patch_files))
+
+            # Check that it can detect a different branch
+            self.assertEqual(3, gitutil.CountCommitsToBranch('second'))
+            with capture_sys_output() as _:
+                _, cover_fname, patch_files = control.prepare_patches(
+                    col, branch='second', count=-1, start=0,
+                    ignore_binary=False)
+            self.assertIsNotNone(cover_fname)
+            self.assertEqual(3, len(patch_files))
         finally:
             os.chdir(orig_dir)

tools/patman/gitutil.py

@@ -49,17 +49,24 @@ def LogCmd(commit_range, git_dir=None, oneline=False, reverse=False,
     cmd.append('--')
     return cmd
 
-def CountCommitsToBranch():
+def CountCommitsToBranch(branch):
     """Returns number of commits between HEAD and the tracking branch.
 
     This looks back to the tracking branch and works out the number of commits
     since then.
 
+    Args:
+        branch: Branch to count from (None for current branch)
+
     Return:
         Number of patches that exist on top of the branch
     """
-    pipe = [LogCmd('@{upstream}..', oneline=True),
-            ['wc', '-l']]
+    if branch:
+        us, msg = GetUpstream('.git', branch)
+        rev_range = '%s..%s' % (us, branch)
+    else:
+        rev_range = '@{upstream}..'
+    pipe = [LogCmd(rev_range, oneline=True), ['wc', '-l']]
     stdout = command.RunPipe(pipe, capture=True, oneline=True).stdout
     patch_count = int(stdout)
     return patch_count
@@ -252,13 +259,14 @@ def Fetch(git_dir=None, work_tree=None):
     if result.return_code != 0:
         raise OSError('git fetch: %s' % result.stderr)
 
-def CreatePatches(start, count, ignore_binary, series):
+def CreatePatches(branch, start, count, ignore_binary, series):
     """Create a series of patches from the top of the current branch.
 
     The patch files are written to the current directory using
     git format-patch.
 
     Args:
+        branch: Branch to create patches from (None for current branch)
         start: Commit to start from: 0=HEAD, 1=next one, etc.
         count: number of commits to include
         ignore_binary: Don't generate patches for binary files
@@ -277,7 +285,8 @@ def CreatePatches(start, count, ignore_binary, series):
     prefix = series.GetPatchPrefix()
     if prefix:
         cmd += ['--subject-prefix=%s' % prefix]
-    cmd += ['HEAD~%d..HEAD~%d' % (start + count, start)]
+    brname = branch or 'HEAD'
+    cmd += ['%s~%d..%s~%d' % (brname, start + count, brname, start)]
 
     stdout = command.RunList(cmd)
     files = stdout.splitlines()

tools/patman/main.py

@@ -31,6 +31,8 @@ from patman import test_checkpatch
 parser = OptionParser()
 parser.add_option('-H', '--full-help', action='store_true', dest='full_help',
        default=False, help='Display the README file')
+parser.add_option('-b', '--branch', type='str',
+                  help="Branch to process (by default, the current branch)")
 parser.add_option('-c', '--count', dest='count', type='int',
        default=-1, help='Automatically create patches from top n commits')
 parser.add_option('-i', '--ignore-errors', action='store_true',

tools/patman/patchstream.py

@@ -512,17 +512,19 @@ def GetMetaDataForList(commit_range, git_dir=None, count=None,
     ps.Finalize()
     return series
 
-def GetMetaData(start, count):
+def GetMetaData(branch, start, count):
     """Reads out patch series metadata from the commits
 
     This does a 'git log' on the relevant commits and pulls out the tags we
     are interested in.
 
     Args:
-        start: Commit to start from: 0=HEAD, 1=next one, etc.
+        branch: Branch to use (None for current branch)
+        start: Commit to start from: 0=branch HEAD, 1=next one, etc.
         count: Number of commits to list
     """
-    return GetMetaDataForList('HEAD~%d' % start, None, count)
+    return GetMetaDataForList('%s~%d' % (branch if branch else 'HEAD', start),
+                              None, count)
 
 def GetMetaDataForTest(text):
     """Process metadata from a file containing a git log. Used for tests