Compute files-changed better in the face of merges
This finds the first unknown parent, instead of finding the oldest
commit that only exists on the branch
diff --git a/tools/wpt/testfiles.py b/tools/wpt/testfiles.py
index e6e673d..d7779fe 100644
--- a/tools/wpt/testfiles.py
+++ b/tools/wpt/testfiles.py
@@ -6,6 +6,8 @@
import subprocess
import sys
+from collections import OrderedDict
+
from ..manifest import manifest, update
here = os.path.dirname(__file__)
@@ -42,25 +44,45 @@
# This is a PR, so the base branch is in TRAVIS_BRANCH
travis_branch = os.environ.get("TRAVIS_BRANCH")
assert travis_branch, "TRAVIS_BRANCH environment variable is defined"
- branch_point = git("rev-parse", travis_branch)
+ branch_point = git("merge-base", "HEAD", travis_branch)
else:
# Otherwise we aren't on a PR, so we try to find commits that are only in the
# current branch c.f.
# http://stackoverflow.com/questions/13460152/find-first-ancestor-commit-in-another-branch
+
+ # parse HEAD into an object ref
head = git("rev-parse", "HEAD")
- not_heads = [item for item in git("rev-parse", "--not", "--all").split("\n")
- if item.strip() and head not in item]
- commits = git("rev-list", "HEAD", *not_heads).split("\n")
+
+ # get everything in refs/heads and refs/remotes that doesn't include HEAD
+ not_heads = [item for item in git("rev-parse", "--not", "--branches", "--remotes").split("\n")
+ if item != "^%s" % head]
+
+ # get all commits on HEAD but not reachable from anything in not_heads
+ commits = git("rev-list", "--topo-order", "--parents", "HEAD", *not_heads)
+ commit_parents = OrderedDict()
+ if commits:
+ for line in commits.split("\n"):
+ line_commits = line.split(" ")
+ commit_parents[line_commits[0]] = line_commits[1:]
+
branch_point = None
- if len(commits):
- first_commit = commits[-1]
- if first_commit:
- branch_point = git("rev-parse", first_commit + "^")
+
+ # if there are any commits, take the first parent that is not in commits
+ for commit, parents in commit_parents.iteritems():
+ for parent in parents:
+ if parent not in commit_parents:
+ branch_point = parent
+ break
+
+ if branch_point:
+ break
+
+ # if we had any commits, we should now have a branch point
+ assert branch_point or not commit_parents
# The above heuristic will fail in the following cases:
#
- # - The current branch has fallen behind the version retrieved via the above
- # `fetch` invocation
+ # - The current branch has fallen behind the remote version
# - Changes on the current branch were rebased and therefore do not exist on any
# other branch. This will result in the selection of a commit that is earlier
# in the history than desired (as determined by calculating the later of the
