Issue 2752 - Automate translation download

ensure_dependencies.py

Index: ensure_dependencies.py
===================================================================
--- a/ensure_dependencies.py
+++ b/ensure_dependencies.py
@@ -34,6 +34,10 @@
   buildtools = buildtools hg:016d16f7137b git:f3f8692f82e5
 """
 
+SKIP_DEPENDENCY_UPDATES = os.environ.get(
+  "SKIP_DEPENDENCY_UPDATES", ""
+).lower() not in ("", "0", "false")
+
 class Mercurial():
   def istype(self, repodir):
     return os.path.exists(os.path.join(repodir, ".hg"))
@@ -97,7 +101,20 @@
     return subprocess.check_output(command, cwd=repo).strip()
 
   def pull(self, repo):
+    # Fetch tracked branches, new tags and the list of available remote branches
     subprocess.check_call(["git", "fetch", "--quiet", "--all", "--tags"], cwd=repo)
+    # Next we need to ensure all remote branches are tracked
+    newly_tracked = False
+    remotes = subprocess.check_output(["git", "branch", "--remotes"], cwd=repo)
+    for match in re.finditer(r"^\s*(origin/(\S+))$", remotes, re.M):
+      remote, local = match.groups()
+      with open(os.devnull, "wb") as devnull:
+        if subprocess.call(["git", "branch", "--track", local, remote],
+                           cwd=repo, stdout=devnull, stderr=devnull) == 0:
+          newly_tracked = True
+    # Finally fetch any newly tracked remote branches
+    if newly_tracked:
+      subprocess.check_call(["git", "fetch", "--quiet", "origin"], cwd=repo)
 
   def update(self, repo, rev):
     subprocess.check_call(["git", "checkout", "--quiet", rev], cwd=repo)
@@ -167,7 +184,7 @@
 
 def safe_join(path, subpath):
   # This has been inspired by Flask's safe_join() function
-  forbidden = set([os.sep, os.altsep]) - set([posixpath.sep, None])
+  forbidden = {os.sep, os.altsep} - {posixpath.sep, None}
   if any(sep in subpath for sep in forbidden):
     raise Exception("Illegal directory separator in dependency path %s" % subpath)
 
@@ -188,6 +205,11 @@
   if os.path.exists(target):
     return
 
+  if SKIP_DEPENDENCY_UPDATES:
+    logging.warning("SKIP_DEPENDENCY_UPDATES environment variable set, "
+                    "%s not cloned", target)
+    return
+
   parenttype = get_repo_type(parentrepo)
   type = None
   for key in roots:
@@ -227,15 +249,21 @@
     return
 
   resolved_revision = repo_types[type].get_revision_id(target, revision)
-  if not resolved_revision:
-    logging.info("Revision %s is unknown, downloading remote changes" % revision)
-    repo_types[type].pull(target)
-    resolved_revision = repo_types[type].get_revision_id(target, revision)
+  current_revision = repo_types[type].get_revision_id(target)
+
+  if resolved_revision != current_revision:
+    if SKIP_DEPENDENCY_UPDATES:
+      logging.warning("SKIP_DEPENDENCY_UPDATES environment variable set, "
+                      "%s not checked out to %s", target, revision)
+      return
+
     if not resolved_revision:
-      raise Exception("Failed to resolve revision %s" % revision)
+      logging.info("Revision %s is unknown, downloading remote changes" % revision)
+      repo_types[type].pull(target)
+      resolved_revision = repo_types[type].get_revision_id(target, revision)
+      if not resolved_revision:
+        raise Exception("Failed to resolve revision %s" % revision)
 
-  current_revision = repo_types[type].get_revision_id(target)
-  if resolved_revision != current_revision:
     logging.info("Updating repository %s to revision %s" % (target, resolved_revision))
     repo_types[type].update(target, resolved_revision)
 
@@ -247,6 +275,7 @@
     return
   if level >= 10:
     logging.warning("Too much subrepository nesting, ignoring %s" % repo)
+    return
 
   if overrideroots is not None:
     config["_root"] = overrideroots