[RFC] dim: Add warncheck subcommand

[Jani Nikula]

On Thu, 24 May 2018, Arkadiusz Hiler <arkadiusz.hiler at intel.com> wrote:
> This subcommand runs 'make W=1' on the provided range.
>
> Signed-off-by: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
> ---
>  dim     | 38 ++++++++++++++++++++++++++++++++++++++
>  dim.rst |  7 +++++++
>  2 files changed, 45 insertions(+)
>
> diff --git a/dim b/dim
> index ed26033f5aba..988e83e691c6 100755
> --- a/dim
> +++ b/dim
> @@ -1506,6 +1506,44 @@ function dim_sparse
>  	return $rv
>  }
>  
> +function dim_warncheck
> +{
> +    _restore_head_on_exit

Please use tabs for indentation throughout.

> +
> +	local range make_output make_rc commits
> +
> +	range=$(rangeish "${1:-}")
> +    commits=( $(git rev-list --reverse $range) )
> +
> +    git checkout --detach  ${commits[0]}~ > /dev/null 2>&1
> +
> +    if ! make -j$(nproc) W=1 > /dev/null 2>&1; then
> +        echo "The base for the provided range does not build cleanly."
> +        echo "Commit: $(git log -n1 --format='%s' HEAD)"
> +        echo "Bailing out to cut on the noise."
> +        return 1
> +    fi
> +
> +	for commit in "${commits[@]}"; do

How about doing

	baseline="${commits[0]}~"

	for commit in $baseline "${commits[@]}"; do

and handling the baseline in the same loop? In the error case, you can
check if [[ "$commit" = "$baseline" ]] and output a different error
message.

> +        git checkout --detach $commit >/dev/null 2>&1
> +
> +        set +e
> +        make_output="$(make W=1 2>&1)"
> +        make_rc=$?
> +        set -e
> +
> +        if [ "$make_rc" -ne 0 ]; then
> +            echo "Commit: $(git log -n1 --format='%s' $commit)"

We have dim_cite function to pretty format commits.

> +            echo "$make_output"

Please use echoerr for error messages throughout.

> +
> +            # error will probably propagate, let's cut the noise
> +            echo

I'm not fond of superfluous whitespace in output.

> +            echo "Quitting early. Please fix and check the other commits as well."
> +            return 1
> +        fi
> +	done
> +}
> +
>  function dim_checker
>  {
>  	rm -f drivers/gpu/drm/i915/*.o drivers/gpu/drm/i915/*.ko
> diff --git a/dim.rst b/dim.rst
> index e2c5fd6e6d0a..c73af992243f 100644
> --- a/dim.rst
> +++ b/dim.rst
> @@ -144,6 +144,13 @@ Run sparse on the files changed by the given commit range.
>  If no commit-ish is passed, defaults to HEAD^..HEAD. If one commit-ish is passed
>  instead of a range, the range commit-ish..HEAD is used.
>  
> +warncheck [*commit-ish* [.. *commit-ish*]]
> +---------------------------------------

Doesn't make check complain about this? Underline should be the same
length as the heading.

> +Runs incremental make W=1 on the given commit range.
> +
> +If no commit-ish is passed, defaults to HEAD^..HEAD. If one commit-ish is passed
> +instead of a range, the range commit-ish..HEAD is used.
> +
>  checker
>  -------
>  Run sparse on drm/i915.

-- 
Jani Nikula, Intel Open Source Graphics Center