util: Add a tool to list outgoing/incoming changes

Add a small Python script that uses Gerrit's Change-Id: tags to list
incoming and outgoing changes.

Change-Id: Iea1757b2d64a57a4c7b4e47718cfcaa725a99615
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2329
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

util/maint/list_changes.py

@@ -0,0 +1,206 @@
+#!/usr/bin/env python2
+#
+# Copyright (c) 2017 ARM Limited
+# All rights reserved
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Andreas Sandberg
+
+
+import subprocess
+import re
+from functools import wraps
+
+class Commit(object):
+    _re_tag = re.compile(r"^((?:\w|-)+): (.*)$")
+
+    def __init__(self, rev):
+        self.rev = rev
+        self._log = None
+        self._tags = None
+
+    def _git(self, args):
+        return subprocess.check_output([ "git", ] + args)
+
+    @property
+    def log(self):
+        """Log message belonging to a commit returned as a list with on line
+        per element.
+
+        """
+        if self._log is None:
+            self._log = self._git(
+                ["show", "--format=%B", "--no-patch", str(self.rev) ]
+            ).rstrip("\n").split("\n")
+        return self._log
+
+    @property
+    def tags(self):
+        """Get all commit message tags in the current commit.
+
+        Returns: { tag, [ value, ... ] }
+
+        """
+        if self._tags is None:
+            tags = {}
+            for l in self.log[1:]:
+                m = Commit._re_tag.match(l)
+                if m:
+                    key, value = m.group(1), m.group(2)
+                    try:
+                        tags[key].append(value)
+                    except KeyError:
+                        tags[key] = [ value ]
+            self._tags = tags
+
+        return self._tags
+
+    @property
+    def change_id(self):
+        """Get the Change-Id tag from the commit
+
+        Returns: A change ID or None if no change ID has been
+        specified.
+
+        """
+        try:
+            cids = self.tags["Change-Id"]
+        except KeyError:
+            return None
+
+        assert len(cids) == 1
+        return cids[0]
+
+    def __str__(self):
+        return "%s: %s" % (self.rev[0:8], self.log[0])
+
+def list_revs(upstream, branch):
+    """Get a generator that lists git revisions that exist in 'branch' but
+    not in 'upstream'.
+
+    Returns: Generator of Commit objects
+
+    """
+
+    changes = subprocess.check_output(
+        [ "git", "rev-list", "%s..%s" % (upstream, branch) ])
+
+    if changes == "":
+        return
+
+    for rev in changes.rstrip("\n").split("\n"):
+        assert rev != ""
+        yield Commit(rev)
+
+def list_changes(upstream, feature):
+    feature_revs = tuple(list_revs(upstream, feature))
+    upstream_revs = tuple(list_revs(feature, upstream))
+
+    feature_cids = dict([
+        (c.change_id, c) for c in feature_revs if c.change_id is not None ])
+    upstream_cids = dict([
+        (c.change_id, c) for c in upstream_revs if c.change_id is not None ])
+
+    incoming = filter(
+        lambda r: r.change_id and r.change_id not in feature_cids,
+        reversed(upstream_revs))
+    outgoing = filter(
+        lambda r: r.change_id and r.change_id not in upstream_cids,
+        reversed(feature_revs))
+    common = filter(
+        lambda r: r.change_id in upstream_cids,
+        reversed(feature_revs))
+    upstream_unknown = filter(
+        lambda r: r.change_id is None,
+        reversed(upstream_revs))
+    feature_unknown = filter(
+        lambda r: r.change_id is None,
+        reversed(feature_revs))
+
+    return incoming, outgoing, common, upstream_unknown, feature_unknown
+
+def _main():
+    import argparse
+    parser = argparse.ArgumentParser(
+        description="List incoming and outgoing changes in a feature branch")
+
+    parser.add_argument("--upstream", "-u", type=str, default="origin/master",
+                        help="Upstream branch for comparison. " \
+                        "Default: %(default)s")
+    parser.add_argument("--feature", "-f", type=str, default="HEAD",
+                        help="Feature branch for comparison. " \
+                        "Default: %(default)s")
+    parser.add_argument("--show-unknown", action="store_true",
+                        help="Print changes without Change-Id tags")
+    parser.add_argument("--show-common", action="store_true",
+                        help="Print common changes")
+
+    args = parser.parse_args()
+
+    incoming, outgoing, common, upstream_unknown, feature_unknown = \
+        list_changes(args.upstream, args.feature)
+
+    if incoming:
+        print "Incoming changes:"
+        for rev in incoming:
+            print rev
+        print
+
+    if args.show_unknown and upstream_unknown:
+        print "Upstream changes without change IDs:"
+        for rev in upstream_unknown:
+            print rev
+        print
+
+    if outgoing:
+        print "Outgoing changes:"
+        for rev in outgoing:
+            print rev
+        print
+
+    if args.show_common and common:
+        print "Common changes:"
+        for rev in common:
+            print rev
+        print
+
+    if args.show_unknown and feature_unknown:
+        print "Outgoing changes without change IDs:"
+        for rev in feature_unknown:
+            print rev
+
+
+
+if __name__ == "__main__":
+    _main()