Override the manifest for the entire command

When a manifest file is overridden, remember that and keep using the
override for the remainder of the process.  If we need to revert it,
make the override name evaluate False.

Change-Id: I1eee05fec6988c1ee4a3c751c4b540d5b5d11797
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/335136
Tested-by: LaMont Jones <lamontjones@google.com>
Reviewed-by: Mike Frysinger <vapier@google.com>

main.py

@@ -310,7 +310,7 @@ class _Repo(object):
         # (sub)manifest, and then any child submanifests.
         result = cmd.Execute(copts, cargs)
         for submanifest in repo_client.manifest.submanifests.values():
-          spec = submanifest.ToSubmanifestSpec(root=repo_client.outer_client)
+          spec = submanifest.ToSubmanifestSpec()
           gopts.submanifest_path = submanifest.repo_client.path_prefix
           child_argv = argv[:]
           child_argv.append('--no-outer-manifest')

manifest_xml.py

@@ -215,8 +215,9 @@ class _XmlSubmanifest:
     manifestName: a string, the submanifest file name.
     groups: a list of strings, the groups to add to all projects in the submanifest.
     path: a string, the relative path for the submanifest checkout.
+    parent: an XmlManifest, the parent manifest.
     annotations: (derived) a list of annotations.
-    present: (derived) a boolean, whether the submanifest's manifest file is present.
+    present: (derived) a boolean, whether the sub manifest file is present.
   """
   def __init__(self,
                name,
@@ -234,6 +235,7 @@ class _XmlSubmanifest:
     self.manifestName = manifestName
     self.groups = groups
     self.path = path
+    self.parent = parent
     self.annotations = []
     outer_client = parent._outer_client or parent
     if self.remote and not self.project:
@@ -268,10 +270,10 @@ class _XmlSubmanifest:
   def __ne__(self, other):
     return not self.__eq__(other)
 
-  def ToSubmanifestSpec(self, root):
+  def ToSubmanifestSpec(self):
     """Return a SubmanifestSpec object, populating attributes"""
-    mp = root.manifestProject
-    remote = root.remotes[self.remote or root.default.remote.name]
+    mp = self.parent.manifestProject
+    remote = self.parent.remotes[self.remote or self.parent.default.remote.name]
     # If a project was given, generate the url from the remote and project.
     # If not, use this manifestProject's url.
     if self.project:
@@ -348,6 +350,11 @@ class XmlManifest(object):
     if manifest_file != os.path.abspath(manifest_file):
       raise ManifestParseError('manifest_file must be abspath')
     self.manifestFile = manifest_file
+    if not outer_client or outer_client == self:
+      # manifestFileOverrides only exists in the outer_client's manifest, since
+      # that is the only instance left when Unload() is called on the outer
+      # manifest.
+      self.manifestFileOverrides = {}
     self.local_manifests = local_manifests
     self._load_local_manifests = True
     self.parent_groups = parent_groups
@@ -396,14 +403,10 @@ class XmlManifest(object):
       if not os.path.isfile(path):
         raise ManifestParseError('manifest %s not found' % name)
 
-    old = self.manifestFile
-    try:
     self._load_local_manifests = load_local_manifests
-      self.manifestFile = path
+    self._outer_client.manifestFileOverrides[self.path_prefix] = path
     self.Unload()
     self._Load()
-    finally:
-      self.manifestFile = old
 
   def Link(self, name):
     """Update the repo metadata to use a different manifest.
@@ -880,6 +883,10 @@ https://gerrit.googlesource.com/git-repo/+/HEAD/docs/manifest-format.md
     exclude = self.manifest.manifestProject.partial_clone_exclude or ''
     return set(x.strip() for x in exclude.split(','))
 
+  def SetManifestOverride(self, path):
+    """Override manifestFile.  The caller must call Unload()"""
+    self._outer_client.manifest.manifestFileOverrides[self.path_prefix] = path
+
   @property
   def UseLocalManifests(self):
     return self._load_local_manifests
@@ -1005,6 +1012,12 @@ https://gerrit.googlesource.com/git-repo/+/HEAD/docs/manifest-format.md
         # This will load all clients.
         self._outer_client._Load(initial_client=self)
 
+      savedManifestFile = self.manifestFile
+      override = self._outer_client.manifestFileOverrides.get(self.path_prefix)
+      if override:
+        self.manifestFile = override
+
+      try:
         m = self.manifestProject
         b = m.GetBranch(m.CurrentBranch).merge
         if b is not None and b.startswith(R_HEADS):
@@ -1050,12 +1063,15 @@ https://gerrit.googlesource.com/git-repo/+/HEAD/docs/manifest-format.md
           self._AddMetaProjectMirror(self.manifestProject)
 
         self._loaded = True
+      finally:
+        if override:
+          self.manifestFile = savedManifestFile
 
       # Now that we have loaded this manifest, load any submanifest  manifests
       # as well.  We need to do this after self._loaded is set to avoid looping.
       for name in self._submanifests:
         tree = self._submanifests[name]
-        spec = tree.ToSubmanifestSpec(self)
+        spec = tree.ToSubmanifestSpec()
         present = os.path.exists(os.path.join(self.subdir, MANIFEST_FILE_NAME))
         if present and tree.present and not tree.repo_client:
           if initial_client and initial_client.topdir == self.topdir:

project.py

@@ -3760,7 +3760,7 @@ class ManifestProject(MetaProject):
 
     if not this_manifest_only:
       for submanifest in self.manifest.submanifests.values():
-        spec = submanifest.ToSubmanifestSpec(root=self.manifest.outer_client)
+        spec = submanifest.ToSubmanifestSpec()
         submanifest.repo_client.manifestProject.Sync(
             manifest_url=spec.manifestUrl,
             manifest_branch=spec.revision,