1 files changed, 89 insertions, 0 deletions
diff --git a/testing/web-platform/manifestupdate.py b/testing/web-platform/manifestupdate.py
new file mode 100644
index 000000000..7b15a55eb
--- /dev/null
+++ b/testing/web-platform/manifestupdate.py
@@ -0,0 +1,89 @@
+import argparse
+import imp
+import os
+import sys
+
+from mozlog.structured import commandline
+from wptrunner.wptcommandline import get_test_paths, set_from_config
+from wptrunner.testloader import ManifestLoader
+
+def create_parser():
+    p = argparse.ArgumentParser()
+    p.add_argument("--check-clean", action="store_true",
+                   help="Check that updating the manifest doesn't lead to any changes")
+    commandline.add_logging_group(p)
+
+    return p
+
+
+def update(logger, wpt_dir, check_clean=True):
+    localpaths = imp.load_source("localpaths",
+                                 os.path.join(wpt_dir, "tests", "tools", "localpaths.py"))
+    kwargs = {"config": os.path.join(wpt_dir, "wptrunner.ini"),
+              "tests_root": None,
+              "metadata_root": None}
+
+    set_from_config(kwargs)
+    config = kwargs["config"]
+    test_paths = get_test_paths(config)
+
+    if check_clean:
+        old_manifests = {}
+        for data in test_paths.itervalues():
+            path = os.path.join(data["metadata_path"], "MANIFEST.json")
+            with open(path) as f:
+                old_manifests[path] = f.readlines()
+
+    try:
+        ManifestLoader(test_paths, force_manifest_update=True).load()
+
+        rv = 0
+
+        if check_clean:
+            clean = diff_manifests(logger, old_manifests)
+            if not clean:
+                rv = 1
+    finally:
+        if check_clean:
+            for path, data in old_manifests.iteritems():
+                logger.info("Restoring manifest %s" % path)
+                with open(path, "w") as f:
+                    f.writelines(data)
+
+    return rv
+
+def diff_manifests(logger, old_manifests):
+    logger.info("Diffing old and new manifests")
+    import difflib
+
+    clean = True
+    for path, old in old_manifests.iteritems():
+        with open(path) as f:
+            new = f.readlines()
+
+        if old != new:
+            clean = False
+            sm = difflib.SequenceMatcher(a=old, b=new)
+            for group in sm.get_grouped_opcodes():
+                logged = False
+                message = []
+                for op, old_0, old_1, new_0, new_1 in group:
+                    if op != "equal" and not logged:
+                        logged = True
+                        logger.lint_error(path=path,
+                                          message="Manifest changed",
+                                          lineno=(old_0 + 1),
+                                          source="\n".join(old[old_0:old_1]),
+                                          linter="wpt-manifest")
+                    if op == "equal":
+                        message.extend(' ' + line for line in old[old_0:old_1])
+                    if op in ('replace', 'delete'):
+                        message.extend('-' + line for line in old[old_0:old_1])
+                    if op in ('replace', 'insert'):
+                        message.extend('+' + line for line in new[new_0:new_1])
+                logger.info("".join(message))
+    if clean:
+        logger.info("No differences found")
+
+    return clean
+