v3gitk: Add a "Copy commit summary" command

> When referring to earlier commits in commit messages or other text, one
> of the established formats is
>
>     <abbrev-sha> ("<summary>", <author-date>)
>
> Add a "Copy commit summary" command to the context menu that puts this
> text for the currently selected commit on the clipboard. This makes it
> easy for our users to create well-formatted commit references.
>
> The <abbrev-sha> is produced with the %h format specifier to make it
> unique. Its minimum length can be controlled with the config setting
> core.abbrev.
>
> Signed-off-by: Beat Bolli <dev+git@drbeat.li>
> Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
> Reviewed-by: Johannes Sixt <j6t@kdbg.org>

> Cc: Paul Mackerras <paulus@samba.org>
>
> ---
> Changes since v2:
> - call git log to produce a unique <abbrev-sha>
> - use the short date format
>
> Changes since v1:
> - drop the "commit " literal in front of the <abbrev-sha>
> ---
>  gitk-git/gitk | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/gitk-git/gitk b/gitk-git/gitk
> index 9a2daf3..4915f53 100755
> --- a/gitk-git/gitk
> +++ b/gitk-git/gitk
> @@ -2617,6 +2617,7 @@ proc makewindow {} {
>         {mc "Diff selected -> this" command {diffvssel 1}}
>         {mc "Make patch" command mkpatch}
>         {mc "Create tag" command mktag}
> +       {mc "Copy commit summary" command copysummary}
>         {mc "Write commit to file" command writecommit}
>         {mc "Create new branch" command mkbranch}
>         {mc "Cherry-pick this commit" command cherrypick}
> @@ -9341,6 +9342,17 @@ proc mktaggo {} {
>      mktagcan
>  }
>
> +proc copysummary {} {
> +    global rowmenuid
> +
> +    set format "%h (\"%s\", %ad)"
> +    set summary [exec git show -s --pretty=format:$format --date=short \
> +                 $rowmenuid]
> +
> +    clipboard clear
> +    clipboard append $summary
> +}
> +
>  proc writecommit {} {
>      global rowmenuid wrcomtop commitinfo wrcomcmd NS
>
> --
> 2.4.0

>> Signed-off-by: Beat Bolli <dev+git@drbeat.li>
>> Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
>> Reviewed-by: Johannes Sixt <j6t@kdbg.org>
>
> You should drop these Reviewed-by: footers, as they imply that the
> code was thoroughly digested and the implementation deemed correct.

>> +proc copysummary {} {
>> +    global rowmenuid
>> +
>> +    set format "%h (\"%s\", %ad)"
>> +    set summary [exec git show -s --pretty=format:$format --date=short \
>> +                 $rowmenuid]
>> +
>> +    clipboard clear
>> +    clipboard append $summary
>> +}
>> +

> Eric Sunshine <sunshine@sunshineco.com> writes:
> 
>>> Signed-off-by: Beat Bolli <dev+git@drbeat.li>
>>> Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
>>> Reviewed-by: Johannes Sixt <j6t@kdbg.org>
>>
>> You should drop these Reviewed-by: footers, as they imply that the
>> code was thoroughly digested and the implementation deemed correct.
> 
> ... and the most importantly, the named people said that themselves.
> 
> I do not think that happened here (yet).
> 
>>> +proc copysummary {} {
>>> +    global rowmenuid
>>> +
>>> +    set format "%h (\"%s\", %ad)"
>>> +    set summary [exec git show -s --pretty=format:$format --date=short \
>>> +                 $rowmenuid]
>>> +
>>> +    clipboard clear
>>> +    clipboard append $summary
>>> +}
>>> +
> 
> I think this is a reasonable implementation.  The usual "spawning a
> process for each commit is too expensive" would not apply, because
> it is done on demand only for the single commit that the end-user
> specified.