2017145 - Switch the gtest harness to structured logging

Status: ASSIGNED

(Testing :: GTest, enhancement)

Description

[Florian Quèze [:florian]]

This will enable seeing much nicer data in resource usage profiles for the GTest jobs.

Example profile with the patch: https://share.firefox.dev/4roXvb9
Example profile without the patch: https://share.firefox.dev/4kBM1hK

The output when running ./mach gtest locally will also look a lot more like the output of running mach test for xpcshell tests.

Comment 1

[Florian Quèze [:florian]]

Attachment: Bug 2017145 - Switch the gtest harness to structured logging, r=ahal!,padenot!.

GTest was still using unstructured TBPL-format output.
This switches it to emit mozlog-compatible structured JSON from the C++ side
and properly consume it on the Python side, matching what mochitest and
xpcshell already do.

C++ (testing/gtest/mozilla/GTestRunner.cpp):

• MozillaPrinter now emits structured JSON actions (suite_start, group_start,
  test_start, test_status, test_end, group_end, suite_end) instead of
  TBPL-formatted text (TEST-START, TEST-PASS, TEST-UNEXPECTED-FAIL).
• Added group_start/group_end via OnTestSuiteStart/OnTestSuiteEnd for
  per-suite markers in resource-usage profiles.
• Added JsonEscape helper for safe JSON string encoding.
• Always installed (MOZ_TBPL_PARSER conditional removed since every caller
  set it).

mach gtest (python/mozbuild/mozbuild/mach_commands.py):

• Structured JSON lines from the gtest binary are parsed and routed through
  a StructuredLogger with MachFormatter (for human-readable terminal output)
  and ResourceHandler (for ./mach resource-usage profiles).
• Non-JSON output lines are logged as process_output actions so they also
  appear in resource profiles.
• Timestamps are continuous with build output.
• Removed the --tbpl-parser / -t flag (no longer needed).

CI harnesses (testing/gtest/rungtests.py, remotegtests.py):

• Switched from mozlog.unstructured to mozlog.commandline.setup_logging
  with {"raw": sys.stdout}, so mozharness StructuredOutputParser can
  parse the JSON directly.
• Added commandline.add_logging_group to argument parsers.

Mozharness configs:

• Removed gtest from unstructured_suites (android_common.py) and
  unstructured_flavors (linux/mac/win_unittest.py) so mozharness uses
  StructuredOutputParser instead of DesktopUnittestOutputParser.