5 files changed, 90 insertions, 15 deletions

diff --git a/docs/manifest-format.md b/docs/manifest-format.md
index 854e5e1b..ed297ae7 100644
--- a/docs/manifest-format.md
+++ b/docs/manifest-format.md
@@ -103,8 +103,9 @@ following DTD:
   <!ATTLIST repo-hooks enabled-list CDATA #REQUIRED>
 
   <!ELEMENT superproject EMPTY>
-  <!ATTLIST superproject name    CDATA #REQUIRED>
-  <!ATTLIST superproject remote  IDREF #IMPLIED>
+  <!ATTLIST superproject name     CDATA #REQUIRED>
+  <!ATTLIST superproject remote   IDREF #IMPLIED>
+  <!ATTLIST superproject revision CDATA #IMPLIED>
 
   <!ELEMENT contactinfo EMPTY>
   <!ATTLIST contactinfo bugurl  CDATA #REQUIRED>
@@ -432,6 +433,11 @@ same meaning as project's name attribute. See the
 Attribute `remote`: Name of a previously defined remote element.
 If not supplied the remote given by the default element is used.
 
+Attribute `revision`: Name of the Git branch the manifest wants
+to track for this superproject. If not supplied the revision given
+by the remote element is used if applicable, else the default
+element is used.
+
 ### Element contactinfo
 
 ***
diff --git a/git_superproject.py b/git_superproject.py
index 935e1250..ce68690f 100644
--- a/git_superproject.py
+++ b/git_superproject.py
@@ -90,7 +90,7 @@ class Superproject(object):
     self._git_event_log = git_event_log
     self._quiet = quiet
     self._print_messages = print_messages
-    self._branch = self._GetBranch()
+    self._branch = manifest.branch
     self._repodir = os.path.abspath(repodir)
     self._superproject_dir = superproject_dir
     self._superproject_path = os.path.join(self._repodir, superproject_dir)
@@ -100,6 +100,7 @@ class Superproject(object):
     if self._manifest.superproject:
       remote = self._manifest.superproject['remote']
       git_name = hashlib.md5(remote.name.encode('utf8')).hexdigest() + '-'
+      self._branch = self._manifest.superproject['revision']
       self._remote_url = remote.url
     else:
       self._remote_url = None
@@ -116,17 +117,6 @@ class Superproject(object):
     """Returns the manifest path if the path exists or None."""
     return self._manifest_path if os.path.exists(self._manifest_path) else None
 
-  def _GetBranch(self):
-    """Returns the branch name for getting the approved manifest."""
-    p = self._manifest.manifestProject
-    b = p.GetBranch(p.CurrentBranch)
-    if not b:
-      return None
-    branch = b.merge
-    if branch and branch.startswith(R_HEADS):
-      branch = branch[len(R_HEADS):]
-    return branch
-
   def _LogMessage(self, message):
     """Logs message to stderr and _git_event_log."""
     if self._print_messages:
diff --git a/manifest_xml.py b/manifest_xml.py
index 7099d5fe..135c91fb 100644
--- a/manifest_xml.py
+++ b/manifest_xml.py
@@ -507,6 +507,9 @@ https://gerrit.googlesource.com/git-repo/+/HEAD/docs/manifest-format.md
       if not d.remote or remote.orig_name != remoteName:
         remoteName = remote.orig_name
         e.setAttribute('remote', remoteName)
+      revision = remote.revision or d.revisionExpr
+      if not revision or revision != self._superproject['revision']:
+        e.setAttribute('revision', self._superproject['revision'])
       root.appendChild(e)
 
     if self._contactinfo.bugurl != Wrapper().BUG_URL:
@@ -914,6 +917,13 @@ https://gerrit.googlesource.com/git-repo/+/HEAD/docs/manifest-format.md
           raise ManifestParseError("no remote for superproject %s within %s" %
                                    (name, self.manifestFile))
         self._superproject['remote'] = remote.ToRemoteSpec(name)
+        revision = node.getAttribute('revision') or remote.revision
+        if not revision:
+          revision = self._default.revisionExpr
+        if not revision:
+          raise ManifestParseError('no revision for superproject %s within %s' %
+                                   (name, self.manifestFile))
+        self._superproject['revision'] = revision
       if node.nodeName == 'contactinfo':
         bugurl = self._reqatt(node, 'bugurl')
         # This element can be repeated, later entries will clobber earlier ones.
diff --git a/tests/test_git_superproject.py b/tests/test_git_superproject.py
index e9b824d6..a24fc7f0 100644
--- a/tests/test_git_superproject.py
+++ b/tests/test_git_superproject.py
@@ -157,7 +157,7 @@ class SuperprojectTestCase(unittest.TestCase):
 """)
     self._superproject = git_superproject.Superproject(manifest, self.repodir,
                                                        self.git_event_log)
-    with mock.patch.object(self._superproject, '_GetBranch', return_value='junk'):
+    with mock.patch.object(self._superproject, '_branch', 'junk'):
       sync_result = self._superproject.Sync()
       self.assertFalse(sync_result.success)
       self.assertTrue(sync_result.fatal)
diff --git a/tests/test_manifest_xml.py b/tests/test_manifest_xml.py
index 20459d1d..ce422536 100644
--- a/tests/test_manifest_xml.py
+++ b/tests/test_manifest_xml.py
@@ -572,6 +572,7 @@ class SuperProjectElementTests(ManifestParseTestCase):
     self.assertEqual(manifest.superproject['name'], 'superproject')
     self.assertEqual(manifest.superproject['remote'].name, 'test-remote')
     self.assertEqual(manifest.superproject['remote'].url, 'http://localhost/superproject')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/main')
     self.assertEqual(
         sort_attributes(manifest.ToXml().toxml()),
         '<?xml version="1.0" ?><manifest>'
@@ -580,6 +581,72 @@ class SuperProjectElementTests(ManifestParseTestCase):
         '<superproject name="superproject"/>'
         '</manifest>')
 
+  def test_superproject_revision(self):
+    """Check superproject settings with a different revision attribute"""
+    self.maxDiff = None
+    manifest = self.getXmlManifest("""
+<manifest>
+  <remote name="test-remote" fetch="http://localhost" />
+  <default remote="test-remote" revision="refs/heads/main" />
+  <superproject name="superproject" revision="refs/heads/stable" />
+</manifest>
+""")
+    self.assertEqual(manifest.superproject['name'], 'superproject')
+    self.assertEqual(manifest.superproject['remote'].name, 'test-remote')
+    self.assertEqual(manifest.superproject['remote'].url, 'http://localhost/superproject')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/stable')
+    self.assertEqual(
+        sort_attributes(manifest.ToXml().toxml()),
+        '<?xml version="1.0" ?><manifest>'
+        '<remote fetch="http://localhost" name="test-remote"/>'
+        '<default remote="test-remote" revision="refs/heads/main"/>'
+        '<superproject name="superproject" revision="refs/heads/stable"/>'
+        '</manifest>')
+
+  def test_superproject_revision_default_negative(self):
+    """Check superproject settings with a same revision attribute"""
+    self.maxDiff = None
+    manifest = self.getXmlManifest("""
+<manifest>
+  <remote name="test-remote" fetch="http://localhost" />
+  <default remote="test-remote" revision="refs/heads/stable" />
+  <superproject name="superproject" revision="refs/heads/stable" />
+</manifest>
+""")
+    self.assertEqual(manifest.superproject['name'], 'superproject')
+    self.assertEqual(manifest.superproject['remote'].name, 'test-remote')
+    self.assertEqual(manifest.superproject['remote'].url, 'http://localhost/superproject')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/stable')
+    self.assertEqual(
+        sort_attributes(manifest.ToXml().toxml()),
+        '<?xml version="1.0" ?><manifest>'
+        '<remote fetch="http://localhost" name="test-remote"/>'
+        '<default remote="test-remote" revision="refs/heads/stable"/>'
+        '<superproject name="superproject"/>'
+        '</manifest>')
+
+  def test_superproject_revision_remote(self):
+    """Check superproject settings with a same revision attribute"""
+    self.maxDiff = None
+    manifest = self.getXmlManifest("""
+<manifest>
+  <remote name="test-remote" fetch="http://localhost" revision="refs/heads/main" />
+  <default remote="test-remote" />
+  <superproject name="superproject" revision="refs/heads/stable" />
+</manifest>
+""")
+    self.assertEqual(manifest.superproject['name'], 'superproject')
+    self.assertEqual(manifest.superproject['remote'].name, 'test-remote')
+    self.assertEqual(manifest.superproject['remote'].url, 'http://localhost/superproject')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/stable')
+    self.assertEqual(
+        sort_attributes(manifest.ToXml().toxml()),
+        '<?xml version="1.0" ?><manifest>'
+        '<remote fetch="http://localhost" name="test-remote" revision="refs/heads/main"/>'
+        '<default remote="test-remote"/>'
+        '<superproject name="superproject" revision="refs/heads/stable"/>'
+        '</manifest>')
+
   def test_remote(self):
     """Check superproject settings with a remote."""
     manifest = self.getXmlManifest("""
@@ -593,6 +660,7 @@ class SuperProjectElementTests(ManifestParseTestCase):
     self.assertEqual(manifest.superproject['name'], 'platform/superproject')
     self.assertEqual(manifest.superproject['remote'].name, 'superproject-remote')
     self.assertEqual(manifest.superproject['remote'].url, 'http://localhost/platform/superproject')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/main')
     self.assertEqual(
         sort_attributes(manifest.ToXml().toxml()),
         '<?xml version="1.0" ?><manifest>'
@@ -613,6 +681,7 @@ class SuperProjectElementTests(ManifestParseTestCase):
 """)
     self.assertEqual(manifest.superproject['name'], 'superproject')
     self.assertEqual(manifest.superproject['remote'].name, 'default-remote')
+    self.assertEqual(manifest.superproject['revision'], 'refs/heads/main')
     self.assertEqual(
         sort_attributes(manifest.ToXml().toxml()),
         '<?xml version="1.0" ?><manifest>'