45115: vcs_info examples: Make the quilt-patch-dir example friendlier.

- Document that no code at all is necessary for Pareto correctness

- Remove a recommendation to rely on implementation details (${rrn});
  instead, rely only on ${context}, which is a documented API.
This commit is contained in:
Daniel Shahaf 2019-12-21 15:58:25 +00:00
parent fec98a13fd
commit 41e3518589
2 changed files with 21 additions and 12 deletions

View file

@ -1,5 +1,8 @@
2019-12-22 Daniel Shahaf <danielsh@apache.org>
* 45115: Misc/vcs_info-examples: vcs_info examples: Make the
quilt-patch-dir example friendlier.
* 45116: Misc/vcs_info-examples: vcs_info examples: Add an
example of showing Git environment variables.

View file

@ -468,8 +468,16 @@ zstyle ':vcs_info:-quilt-.quilt-standalone:*:*' quilt-patch-dir debian/patches
# and so we want addon mode to also use a $QUILT_PATCHES value of
# `debian/patches' in some directories. In the other directories we never
# want the default `patches' though but a dedicated place for them.
# Say `~/patches/<repository-name>'. Now we'll use some evaluated-style
# magic to achieve all that:
# Say `~/patches/<repository-name>'.
#
# First of all, even without any configuration, vcs_info will do the right
# thing most of the time. Whenever quilt has already run in a directory,
# vcs_info will figure out whether that directory uses `patches' or
# `debian/patches' by interrogating metadata in the `.pc/' subdirectory,
# which quilt creates. To make vcs_info find the patches dir correctly even
# when the `.pc/' directory doesn't exist, read on.
#
# We'll use some evaluated-style magic to achieve that:
zstyle -e ':vcs_info:*.quilt-addon:*:*' quilt-patch-dir 'my-patches-func'
# That runs something called `my-patches-func', and the value of $reply is
@ -486,19 +494,17 @@ function my-patches-func() {
fi
# Now the part about the dedicated directory is a little trickier.
# It requires some knowledge of vcs_info's internals. Not much though.
# Everything about this is described in the manual because this
# variable (plus a few others) may be of interest in hooks, where
# they are available, too.
#
# The variable in question here is `$rrn' which is an abbreviation
# of repository-root-name. if you're in
# The variable in question here is `$context', which is the zstyle
# context used for lookups. Its last component is the repository-root-name,
# or ${rrn} for short. If you're in
# /usr/src/zsh/Functions
# and the repository being
# /usr/src/zsh
# then the value of `$rrn' is `zsh'. Now in case the variable is
# empty (it shouldn't at this point, but you never know), let's
# drop back to quilt's default "patches".
# then the value of `$rrn' would be `zsh'.
local rrn=${context##*:}
# Now, in case the variable is empty (it shouldn't at this point, but you
# never know), let's drop back to quilt's default value, "patches".
if [[ -z ${rrn} ]]; then
reply=( patches )
return 0