From c178beec283ea5815767082cfe5a6dca4dc54b91 Mon Sep 17 00:00:00 2001
From: Timothy Nikkel <tnikkel@gmail.com>
Date: Wed, 16 Sep 2026 23:20:10 -0500
Subject: [PATCH] Don't drop most of the commit date from ./mach vendor
 --check-for-update for some hosts

`check_for_update` splits mach's "<revision> <timestamp>" output on every
space and keeps the second field. For a github-hosted library that second
field is the whole timestamp:

    3f3735e3f39c68d33104add994bfe5d055b32e17 2026-09-09T17:56:48Z

googlesource reports commit dates with spaces in them, so there the second
field is only the weekday and the rest of the date is thrown away:

    3f3735e3f39c68d33104add994bfe5d055b32e17 Wed Sep 09 17:56:48 2026

dateutil resolves a bare "Wed" against today's date, which is how
https://bugzilla.mozilla.org/show_bug.cgi?id=2070891, filed on 2026-09-10 for
a commit made on 2026-09-09, ended up titled "from 2026-09-16 00:00:00": the
next Wednesday, at midnight. libvpx, aom, irregexp and chromium-cdm are
affected the same way.

host_git.py has the same problem more quietly: `git show --format=%ci` gives
"2026-09-16 23:20:10 -0500", so there we kept the date and threw away the
time. Rather than make every host agree on one format, parse whatever the
host reports; dateutil already copes with all of them.
---
 components/mach_vendor.py |  6 +++--
 test.py                   |  3 ++-
 tests/mach_vendor.py      | 53 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 59 insertions(+), 3 deletions(-)
 create mode 100644 tests/mach_vendor.py

diff --git a/components/mach_vendor.py b/components/mach_vendor.py
index 88493dd0..77ca5a6b 100644
--- a/components/mach_vendor.py
+++ b/components/mach_vendor.py
@@ -35,8 +35,10 @@ def check_for_update(self, library):
         if not result:
             return (None, None)
 
-        parts = result.split(" ")
-        return (parts[0], string_date_to_uniform_string_date(parts[1]))
+        # ./mach vendor prints "<revision> <timestamp>", and the timestamp is not
+        # space-free on every host (googlesource: "Wed Sep 09 17:56:48 2026").
+        revision, timestamp = result.split(" ", 1)
+        return (revision, string_date_to_uniform_string_date(timestamp))
 
     @logEntryExit
     def vendor(self, library, revision):
diff --git a/test.py b/test.py
index ed608d16..34c463ac 100755
--- a/test.py
+++ b/test.py
@@ -21,7 +21,8 @@
     "library",
     "lambda_capture",
     "class_passing",
-    "frequency"
+    "frequency",
+    "mach_vendor"
 ]
 
 modules = []
diff --git a/tests/mach_vendor.py b/tests/mach_vendor.py
new file mode 100644
index 00000000..3c014235
--- /dev/null
+++ b/tests/mach_vendor.py
@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import sys
+import unittest
+
+sys.path.append(".")
+sys.path.append("..")
+
+from components.logging import SimpleLoggerConfig
+from components.mach_vendor import VendorProvider
+from components.utilities import Struct
+from tests.mock_commandprovider import TestCommandProvider
+
+LIBRARY = Struct(**{'yaml_path': 'media/libyuv/moz.yaml'})
+REVISION = "3f3735e3f39c68d33104add994bfe5d055b32e17"
+
+
+class TestVendorProvider(unittest.TestCase):
+    def _check_for_update(self, mach_output):
+        """Run check_for_update against a mocked `./mach vendor` stdout."""
+        commandProvider = TestCommandProvider({
+            'test_mappings': {
+                "./mach vendor --check-for-update": lambda: mach_output
+            }
+        })
+        commandProvider.update_config(SimpleLoggerConfig)
+
+        vendorProvider = VendorProvider({})
+        vendorProvider.update_config(dict(SimpleLoggerConfig, CommandProvider=commandProvider))
+        return vendorProvider.check_for_update(LIBRARY)
+
+    def testGooglesourceTimestamp(self):
+        # googlesource reports commit dates in git's default format, so the
+        # timestamp field contains spaces and must not be split on them.
+        self.assertEqual(
+            self._check_for_update(REVISION + " Wed Sep 09 17:56:48 2026"),
+            (REVISION, "2026-09-09 17:56:48"))
+
+    def testISO8601Timestamp(self):
+        self.assertEqual(
+            self._check_for_update(REVISION + " 2026-09-09T17:56:48Z"),
+            (REVISION, "2026-09-09 17:56:48"))
+
+    def testNoUpdateAvailable(self):
+        self.assertEqual(self._check_for_update(""), (None, None))
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=0)