Subject: Re: [PATCH 8/8] ci: use Meson's new `--slice` option

From: Junio C Hamano <[email-masked]>
Date: Mon, 07 Jul 2025 17:16:03 -0700

Patrick Steinhardt <[email-masked]> writes:

> As executing our test suite is notoriously slow on Windows we use matrix
> jobs in our CI systems to slice up tests and run them via multiple jobs.
> On Meson this is done with a comparatively complex PowerShell invocation
> as Meson didn't yet have a native way to slice tests like this.
>
> I have upstreamed a new `--slice` option [1] that addresses this use
> case though, which has been merged and released with Meson 1.8. Both
> GitLab and GitHub CI have Meson 1.8.2 available by now, so let's update
> the jobs to use that new option.
>
> [1]: https://github.com/mesonbuild/meson/pull/14092
>
> Signed-off-by: Patrick Steinhardt <[email-masked]>
> ---
>  .github/workflows/main.yml | 2 +-
>  .gitlab-ci.yml             | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)

https://github.com/git/git/actions/runs/16129796573/job/45515034049#step:6:17

unfortunately ends like this:

Run meson test -C build --no-rebuild --print-errorlogs --slice 0/10
  meson test -C build --no-rebuild --print-errorlogs --slice 0/10
  shell: C:\Program Files\PowerShell\7\pwsh.EXE -command ". '{0}'"
  env:
    DEVELOPER: 1
usage: meson test [-h] [--maxfail MAXFAIL] [--repeat REPEAT] [--no-rebuild]
                  [--gdb] [--gdb-path GDB_PATH] [-i] [--list]
                  [--wrapper WRAPPER] [-C WD] [--suite SUITE] [--no-suite SUITE]
                  [--no-stdsplit] [--print-errorlogs] [--benchmark]
                  [--logbase LOGBASE] [-j NUM_PROCESSES] [-v] [-q]
                  [-t TIMEOUT_MULTIPLIER] [--setup SETUP]
                  [--test-args TEST_ARGS] [--max-lines MAX_LINES]
                  [--slice SLICE/NUM_SLICES]
                  [args ...]
meson test: error: argument --slice: SLICE is not a positive integer
Error: Process completed with exit code 1.

> diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
> index 7dbf9f7f123..f0f653bd853 100644
> --- a/.github/workflows/main.yml
> +++ b/.github/workflows/main.yml
> @@ -298,7 +298,7 @@ jobs:
>          path: build
>      - name: Test
>        shell: pwsh
> -      run: meson test -C build --list | Select-Object -Skip 1 | Select-String .* | Group-Object -Property { $_.LineNumber % 10 } | Where-Object Name -EQ ${{ matrix.nr }} | ForEach-Object { meson test -C build --no-rebuild --print-errorlogs $_.Group }
> +      run: meson test -C build --no-rebuild --print-errorlogs --slice ${{ matrix.nr }}/10
>  
>    regular:
>      name: ${{matrix.vector.jobname}} (${{matrix.vector.pool}})
> diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
> index bb6d5b976cd..af10ebb59a3 100644
> --- a/.gitlab-ci.yml
> +++ b/.gitlab-ci.yml
> @@ -178,7 +178,7 @@ test:msvc-meson:
>      - job: "build:msvc-meson"
>        artifacts: true
>    script:
> -    - meson test -C build --list | Select-Object -Skip 1 | Select-String .* | Group-Object -Property { $_.LineNumber % $Env:CI_NODE_TOTAL + 1 } | Where-Object Name -EQ $Env:CI_NODE_INDEX | ForEach-Object { meson test -C build --no-rebuild --print-errorlogs $_.Group; if (!$?) { exit $LASTEXITCODE } }
> +    - meson test -C build --no-rebuild --print-errorlogs --slice $Env:CI_NODE_INDEX/$Env:CI_NODE_TOTAL
>    parallel: 10
>  
>  test:fuzz-smoke-tests: