GITC: Add repo start support.

Add repo start support for GITC checkouts. If the user is in
the GITC FS view, they can now run repo start to check out
the sources and create a new working branch.

When "repo start" is called on a GITC project, the revision
tag is set to an empty string and saved in a new tag:
old-revision. This tells the GITC filesystem to display the
local copy of the sources when being viewed. The local copy
is created by pulling the project sources and the new branch
is created based off the original project revision.

Updated main.py to setup each command's gitc_manifest when
appropriate.

Updated repo sync's logic to sync opened projects and
updating the GITC manifest file for the rest.

Change-Id: I7e4809d1c4fc43c69b26f2f1bebe45aab0cae628

1 files changed, 12 insertions, 6 deletions

diff --git a/project.py b/project.py
index a8d012d2..f964b2fc 100644
--- a/project.py
+++ b/project.py
@@ -572,7 +572,8 @@ class Project(object):
                parent=None,
                is_derived=False,
                dest_branch=None,
-               optimized_fetch=False):
+               optimized_fetch=False,
+               old_revision=None):
     """Init a Project object.
 
     Args:
@@ -596,6 +597,7 @@ class Project(object):
       dest_branch: The branch to which to push changes for review by default.
       optimized_fetch: If True, when a project is set to a sha1 revision, only
                        fetch from the remote if the sha1 is not present locally.
+      old_revision: saved git commit id for open GITC projects.
     """
     self.manifest = manifest
     self.name = name
@@ -643,6 +645,7 @@ class Project(object):
     self.bare_ref = GitRefs(gitdir)
     self.bare_objdir = self._GitGetByExec(self, bare=True, gitdir=objdir)
     self.dest_branch = dest_branch
+    self.old_revision = old_revision
 
     # This will be filled in if a project is later identified to be the
     # project containing repo hooks.
@@ -1195,6 +1198,8 @@ class Project(object):
     self._InitHooks()
 
   def _CopyAndLinkFiles(self):
+    if self.manifest.isGitcClient:
+      return
     for copyfile in self.copyfiles:
       copyfile._Copy()
     for linkfile in self.linkfiles:
@@ -1425,9 +1430,11 @@ class Project(object):
 
 ## Branch Management ##
 
-  def StartBranch(self, name):
+  def StartBranch(self, name, branch_merge=''):
     """Create a new branch off the manifest's revision.
     """
+    if not branch_merge:
+      branch_merge = self.revisionExpr
     head = self.work_git.GetHead()
     if head == (R_HEADS + name):
       return True
@@ -1441,9 +1448,9 @@ class Project(object):
 
     branch = self.GetBranch(name)
     branch.remote = self.GetRemote(self.remote.name)
-    branch.merge = self.revisionExpr
-    if not branch.merge.startswith('refs/') and not ID_RE.match(self.revisionExpr):
-      branch.merge = R_HEADS + self.revisionExpr
+    branch.merge = branch_merge
+    if not branch.merge.startswith('refs/') and not ID_RE.match(branch_merge):
+      branch.merge = R_HEADS + branch_merge
     revid = self.GetRevisionId(all_refs)
 
     if head.startswith(R_HEADS):
@@ -1451,7 +1458,6 @@ class Project(object):
         head = all_refs[head]
       except KeyError:
         head = None
-
     if revid and head and revid == head:
       ref = os.path.join(self.gitdir, R_HEADS + name)
       try: