Auto merge of servo#19062 - jdm:updatewpt6, r=jdm

Update web-platform-tests

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tests/wpt/css-tests/tools/manifest/download.py

@@ -0,0 +1,130 @@
+import argparse
+import gzip
+import json
+import io
+import log
+import os
+from datetime import datetime, timedelta
+
+import urllib2
+
+from vcs import Git
+
+here = os.path.dirname(__file__)
+
+wpt_root = os.path.abspath(os.path.join(here, os.pardir, os.pardir))
+logger = log.get_logger()
+
+
+def abs_path(path):
+    return os.path.abspath(os.path.expanduser(path))
+
+
+def should_download(manifest_path, rebuild_time=timedelta(days=5)):
+    if not os.path.exists(manifest_path):
+        return True
+    mtime = datetime.fromtimestamp(os.path.getmtime(manifest_path))
+    if mtime < datetime.now() - rebuild_time:
+        return True
+    logger.info("Skipping manifest download because existing file is recent")
+    return False
+
+
+def git_commits(repo_root):
+    git = Git.get_func(repo_root)
+    return [item for item in git("log", "--format=%H", "-n50").split("\n") if item]
+
+
+def github_url(commits):
+    try:
+        resp = urllib2.urlopen("https://api.github.com/repos/w3c/web-platform-tests/releases")
+    except Exception:
+        return None
+
+    if resp.code != 200:
+        return None
+
+    try:
+        releases = json.load(resp.fp)
+    except ValueError:
+        logger.warning("Response was not valid JSON")
+        return None
+
+    fallback = None
+    for release in releases:
+        for commit in commits:
+            for item in release["assets"]:
+                if item["name"] == "MANIFEST-%s.json.gz" % commit:
+                    return item["browser_download_url"]
+                elif item["name"] == "MANIFEST.json.gz" and not fallback:
+                    fallback = item["browser_download_url"]
+    if fallback:
+        logger.info("Can't find a commit-specific manifest so just using the most recent one")
+        return fallback
+
+
+def download_manifest(manifest_path, commits_func, url_func, force=False):
+    if not force and not should_download(manifest_path):
+        return False
+
+    commits = commits_func()
+
+    url = url_func(commits)
+    if not url:
+        logger.warning("No generated manifest found")
+        return False
+
+    logger.info("Downloading manifest from %s" % url)
+    try:
+        resp = urllib2.urlopen(url)
+    except Exception:
+        logger.warning("Downloading pregenerated manifest failed")
+        return False
+
+    if resp.code != 200:
+        logger.warning("Downloading pregenerated manifest failed; got HTTP status %d" %
+                       resp.code)
+        return False
+
+    gzf = gzip.GzipFile(fileobj=io.BytesIO(resp.read()))
+
+    try:
+        decompressed = gzf.read()
+    except IOError:
+        logger.warning("Failed to decompress downloaded file")
+        return False
+
+    try:
+        with open(manifest_path, "w") as f:
+            f.write(decompressed)
+    except Exception:
+        logger.warning("Failed to write manifest")
+        return False
+    logger.info("Manifest downloaded")
+    return True
+
+
+def create_parser():
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "-p", "--path", type=abs_path, help="Path to manifest file.")
+    parser.add_argument(
+        "--tests-root", type=abs_path, default=wpt_root, help="Path to root of tests.")
+    parser.add_argument(
+        "--force", action="store_true",
+        help="Always download, even if the existing manifest is recent")
+    return parser
+
+
+def download_from_github(path, tests_root, force=False):
+    return download_manifest(path, lambda: git_commits(tests_root), github_url,
+                             force=force)
+
+
+def run(**kwargs):
+    if kwargs["path"] is None:
+        path = os.path.join(kwargs["tests_root"], "MANIFEST.json")
+    else:
+        path = kwargs["path"]
+    success = download_from_github(path, kwargs["tests_root"], kwargs["force"])
+    return 0 if success else 1