diffpkg: allow to set column width for side-by-side view

The magic values `columns` and `auto` allow to set specific aspects,
with 'auto' as the default value:

- auto: Set width to the maximum line length of all input files
- columns: Set width to the shell defined $COLUMNS env var

Furthermore any number can be passed to set a static width.

1 files changed, 1 insertions, 0 deletions

diff --git a/contrib/completion/zsh/_devtools.in b/contrib/completion/zsh/_devtools.in
index 46e04fb..b93e510 100644
--- a/contrib/completion/zsh/_devtools.in
+++ b/contrib/completion/zsh/_devtools.in
@@ -51,6 +51,7 @@ _diffpkg_args=(
 	'(-u -U --unified)'{-u,-U,--unified}'[Output 3 lines of unified context]'
 	'(-y --side-by-side)'{-y,--side-by-side}'[Output in two columns]'
 	'--color=[Color output]:when:($_colors[*])'
+	'(-W --width=)'{-W,--width=}'[Output at most NUM print columns]:num:(auto columns)'
 	'(-v --verbose)'{-v,--verbose}'[Provide more detailed/unfiltered output]'
 	'(-h --help)'{-h,--help}'[Display usage]'
 	'*:packages:_devtools_completions_all_packages'