Re: [PATCH 1/1] check-docs: fix for setups where executables have an extension

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
> > Sharp eyes, and a *very* good point. The double space is actually required
> > for this patch to work as intended. I added the following explanation to
> > the commit message:
> >
> >     Note that `$(ALL_COMMANDS)` starts with a space, and that is rather
> >     crucial for the `while read how cmd` loop: some of the input lines do
> >     not actually have the form `<how> <cmd>`, but only `<cmd>`, therefore
> >     `$cmd` evaluates to the empty string, and when we are looking for
> >     `* $cmd *` in ` $(ALL_COMMANDS)`, we do find it because the latter
> >     starts with a double space.
> >     In other words, the double space helps us skip the lines that list
> >     only a command.
>
> That sounds more like a bug in the existing set-up even before your
> patch (in fact, these lines are probably from 2007 or so, long
> before you started touching our top-level Makefile heavily).  If we
> want to ignore lines with only one token, I'd rather see it
> explicitly done, e.g.
>
> 	... generate data ... |
> 	while read how cmd
> 	do
> 		# skip a line with a single token
> 		case "$cmd" in "") continue ;; esac
>
> 		# is $cmd part of the known command list?
> 		case " $(ALL_COMMANDS) " in
> 		*" $cmd "*)	;; # skip
> 		*)	echo ... warning ... ;;
> 		esac
> 	done
>
> instead of relying on "if $cmd is empty, then SP + $cmd + SP makes
> double space, so let's have double space somewhere in the list of
> known commands" cuteness.