summary refs log tree commit diff
path: root/Misc/vcs_info-examples
blob: edb0760d113083df201c24953840f158217a8be1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
# A collection of vcs_info usage examples

### Running vcs_info #########################################################

# As always, there's more than one way to skin a cat. Running vcs_info is no
# exception. Here is a rundown of three common ways to get it into action.
#
# All three ways need vcs_info to be marked for autoloading first, so you'd
# do this somewhere in your setup:

autoload -Uz vcs_info

# Episode I: "The prompt_subst way"
# Also known as the Quick-Start-Way. Probably the simplest way to add
# vcs_info functionality to existing setups. You just drop a vcs_info call
# to your `precmd' (or into a `precmd_functions[]' entry) and include a
# single-quoted ${vcs_info_msg_0_} in your PS1 definition:

precmd() { vcs_info }
# This needs prompt_subst set, hence the name. So:
setopt prompt_subst
PS1='%!-%3~ ${vcs_info_msg_0_}%# '

# Episode II: "The way of the psvar"
# With $psvar you got a simple way to get user defined things into your
# prompt without having to set `prompt_subst', which requires extra
# attention to quoting if you like characters like ` in your prompt...
# As described in <http://xana.scru.org/xana2/quanks/vcsinfoprompt/>:

precmd() {
    psvar=()

    vcs_info
    [[ -n $vcs_info_msg_0_ ]] && print -v 'psvar[1]' -Pr -- "$vcs_info_msg_0_"
}

# You can now use `%1v' to drop the $vcs_info_msg_0_ contents in your prompt;
# like this:

PS1="%m%(1v.%F{red}%1v%f.)%# "

# Episode III: "The justsetitinprecmd way"
# This is the way I prefer. When you see it, you may think "Setting that
# variable in precmd() each time? What a waste..."; but let me assure you,
# you're running vcs_info already, setting one variable is not an issue.
#
# You're getting the benefit of being able to programmatically setting your
# prompt, which is nice especially when you're going to do weird things in
# there anyway. Here goes:

precmd() {
    # As always first run the system so everything is setup correctly.
    vcs_info
    # And then just set PS1, RPS1 and whatever you want to. This $PS1
    # is (as with the other examples above too) just an example of a very
    # basic single-line prompt. See "man zshmisc" for details on how to
    # make this less readable. :-)
    if [[ -z ${vcs_info_msg_0_} ]]; then
        # Oh hey, nothing from vcs_info, so we got more space.
        # Let's print a longer part of $PWD...
        PS1="%5~%# "
    else
        # vcs_info found something, that needs space. So a shorter $PWD
        # makes sense.
        PS1="%3~${vcs_info_msg_0_}%# "
    fi
}


### check-for-changes just in some places ####################################

# Some backends (git and mercurial at the time of writing) can tell you
# whether there are local changes in the current repository. While that's
# nice, the actions needed to obtain the information can be potentially
# expensive. So if you're working on something the size of the linux kernel
# or some corporate code monstrosity you may want to think twice about
# enabling the `check-for-changes' style unconditionally.
#
# Zsh's zstyle configuration system let's you do some magic to enable styles
# only depending on some code you're running.
#
# So, what I'm doing is this: I'm keeping my own projects in `~/src/code'.
# There are the projects I want the information for most. They are also
# a lot smaller than the linux kernel so the information can be retrieved
# instantaneously - even on my old laptop at 600MHz. And the following code
# enables `check-for-changes' only in that subtree:

zstyle -e ':vcs_info:git:*' \
    check-for-changes 'estyle-cfc && reply=( true ) || reply=( false )'

function estyle-cfc() {
    local d
    local -a cfc_dirs
    cfc_dirs=(
        ${HOME}/src/code/*(/)
    )

    for d in ${cfc_dirs}; do
        d=${d%/##}
        [[ $PWD == $d(|/*) ]] && return 0
    done
    return 1
}


### Hook Examples ############################################################

# A number of examples in this file revolve around the concept of `hooks'
# in vcs_info. Hooks are places in vcs_info where you may put in your
# own code to achieve something "totally awesome"[tm].
#
# Hooks can be confusing. It's hard to keep track of what's going on.
# In order to help you with that vcs_info can output some debugging
# information when it processes hooks. This will tell you which hooks
# are being run and which functions are attempted to run (and if the
# functions in question were found or not).
#
# If you feel like you need to see what's attempted and where, I suggest
# you use the following line and see for yourself.
zstyle ':vcs_info:*+*:*' debug true

# You can just comment it out (or disable it) again when you've seen enough.
# Debugging is off by default - of course.
zstyle ':vcs_info:*+*:*' debug false

# Further down, every example that uses a function named `+vi-*' uses a hook.


### Truncate Long Hashes

### Truncate a long hash to 12 characters (which is usually unique enough)
# Use zformat syntax (remember %i is the hash): %12.12i

# git:
zstyle ':vcs_info:git*' formats "(%s)-[%12.12i %b]-" # hash & branch


### Fetch the full 40-character Mercurial revision id
# There is no great way to obtain branch, local rev, and untracked changes in
# addition to the full 40-character global rev id with a single invocation of
# Mercurial. This hook obtains the full global rev id using xxd(1) (in the
# same way the use-simple flag does) while retaining all the other vcs_info
# default functionality and information.
zstyle ':vcs_info:hg*+set-message:*' hooks hg-fullglobalrev

# Output the full 40-char global rev id
function +vi-hg-fullglobalrev() {
    local dirstatefile="${hook_com[base]}/.hg/dirstate"
    local grevid="$(xxd -p -l 20 < ${dirstatefile})"
    # Omit %h from your hgrevformat since it will be included below
    hook_com[revision]="${hook_com[revision]} ${grevid}"
}


### Display the existence of files not yet known to VCS

### git: Show marker (T) if there are untracked files in repository
# Make sure you have added staged to your 'formats':  %c
zstyle ':vcs_info:git*+set-message:*' hooks git-untracked

+vi-git-untracked(){
    if [[ $(git rev-parse --is-inside-work-tree 2> /dev/null) == 'true' ]] && \
        git status --porcelain | grep '??' &> /dev/null ; then
        # This will show the marker if there are any untracked files in repo.
        # If instead you want to show the marker only if there are untracked
        # files in $PWD, use:
        #[[ -n $(git ls-files --others --exclude-standard) ]] ; then
        hook_com[staged]+='T'
    fi
}


### Compare local changes to remote changes

### git: Show +N/-N when your local branch is ahead-of or behind remote HEAD.
# Make sure you have added misc to your 'formats':  %m
zstyle ':vcs_info:git*+set-message:*' hooks git-st
function +vi-git-st() {
    local ahead behind
    local -a gitstatus

    # Exit early in case the worktree is on a detached HEAD
    git rev-parse ${hook_com[branch]}@{upstream} >/dev/null 2>&1 || return 0

    local -a ahead_and_behind=(
        $(git rev-list --left-right --count HEAD...${hook_com[branch]}@{upstream} 2>/dev/null)
    )

    ahead=${ahead_and_behind[1]}
    behind=${ahead_and_behind[2]}

    (( $ahead )) && gitstatus+=( "+${ahead}" )
    (( $behind )) && gitstatus+=( "-${behind}" )

    hook_com[misc]+=${(j:/:)gitstatus}
}

### git: Show remote branch name for remote-tracking branches
zstyle ':vcs_info:git*+set-message:*' hooks git-remotebranch

function +vi-git-remotebranch() {
    local remote

    # Are we on a remote-tracking branch?
    remote=${$(git rev-parse --verify ${hook_com[branch]}@{upstream} \
        --symbolic-full-name 2>/dev/null)/refs\/remotes\/}

    # The first test will show a tracking branch whenever there is one. The
    # second test, however, will only show the remote branch's name if it
    # differs from the local one.
    if [[ -n ${remote} ]] ; then
    #if [[ -n ${remote} && ${remote#*/} != ${hook_com[branch]} ]] ; then
        hook_com[branch]="${hook_com[branch]} [${remote}]"
    fi
}


### Derive hook names dynamically
# With the following line:
zstyle -e ':vcs_info:git+set-message:*' hooks 'reply=( ${${(k)functions[(I)[+]vi-git-set-message*]}#+vi-} )'
# Any function named `+vi-git-set-message-<anything>' would be automatically
# registered as a hook. For example:
+vi-git-set-message-foo() {}
+vi-git-set-message-bar() {}
# Both of these functions would be called, even if they are defined after the zstyle is set.


## git: Display pertinent environment variables
# If environment variables such as $GIT_DIR, $GIT_WORK_TREE, etc are set in the
# environment, they'll be shown in the value of the %m expando.
#
# Note that the %m expando is not used by default. To see a change, either change
# `[misc]' to `[branch]', or set the `formats` style to a value that includes `%m'.
zstyle ':vcs_info:git+post-backend:*' hooks git-post-backend-envvars
+vi-git-post-backend-envvars() {
  local param
  # This uses the ${parameters} special variable (provided by the zsh/parameter
  # module), in conjunction with the parameter expansion flags ${(k)foo} and
  # ${(M)foo:#pattern} (documented in "Parameter Expansion" in zshexpn(1))
  # and the (R) subscript flag (documented in "Subscript Flags" in zshparam(1)),
  # to iterate over the names of all environment variables named "GIT_*".  Then
  # it uses the ${(P)foo} parameter expansion flag to show the values of those
  # parameters.
  #
  # The value of ${hook_com[misc]} is substituted for %m in the values of the
  # 'formats' and 'actionformats' styles.
  for param in ${(Mk)parameters[(R)*export*]:#GIT_*}; do
    hook_com[misc]+=";%U${param//'%'/%%}%u=%F{white}${${(P)param}//'%'/%%}%f"
  done
}


### hg: Show marker when the working directory is not on a branch head
# This may indicate that running `hg up` will do something
# NOTE: the branchheads.cache file is not updated with every Mercurial
# operation, so it will sometimes give false positives. Think of this more as a
# hint that you might not be on a branch head instead of the final word.
zstyle ':vcs_info:hg+set-hgrev-format:*' hooks hg-storerev
zstyle ':vcs_info:hg+set-message:*' hooks hg-branchhead

# The hash is available in the hgrev-format hook, store a copy of it in the
# user_data array so we can access it in the second function
function +vi-hg-storerev() {
    user_data[hash]=${hook_com[hash]}
}

function +vi-hg-branchhead() {
    local branchheadsfile i_tiphash i_branchname
    local -a branchheads

    local branchheadsfile=${hook_com[base]}/.hg/branchheads.cache

    # Bail out if any mq patches are applied
    [[ -s ${hook_com[base]}/.hg/patches/status ]] && return 0

    if [[ -r ${branchheadsfile} ]] ; then
        while read -r i_tiphash i_branchname ; do
            branchheads+=( $i_tiphash )
        done < ${branchheadsfile}

        if [[ ! ${branchheads[(i)${user_data[hash]}]} -le ${#branchheads} ]] ; then
            hook_com[revision]="^ ${hook_com[revision]}"
        fi
    fi
}


### Show information about patch series
# This is used with with hg mq, quilt, and git rebases and conflicts.
#
# All these cases have a notion of a "series of patches/commits" that is being
# applied.  The following shows the information about the most recent patch to
# have been applied:
zstyle ':vcs_info:*+gen-applied-string:*' hooks gen-applied-string
function +vi-gen-applied-string() {
  # Separate the patch id from the patch log message.
  if [[ $1 == *\ * ]]; then
    local patch_name_or_filename="${1%% *}"
    local patch_description="${1#* }"
  else
    local patch_name_or_filename="$1"
    local patch_description=""
  fi

  # Apply escaping; see `Oddities' in the manual.
  patch_name_or_filename=${patch_name_or_filename//'%'/%%}
  patch_description=${patch_description//'%'/%%}

  # Apply different colouring to the patch description.
  if [[ -n ${patch_description} ]]; then
    patch_description="%F{yellow}${patch_description}%f"
  fi

  # Re-assemble $1, escaped and coloured.
  hook_com[applied-string]="${patch_name_or_filename} ${patch_description}"
  ret=1
}
# The value of hook_com[applied-string] is incorporated into the %m expando
# (see the 'patch-format' style for details), which is not included in the
# 'formats' and 'actionformats' style by default, so to actually use this,
# you'll need to add %m (or %Q under quilt in add-on mode) to your 'formats'
# and 'actionformats' styles, as in:
# 
#     zstyle ':vcs_info:*' actionformats ' (%s)-[%b|%a]%u%c- %m'
#     zstyle ':vcs_info:*' formats ' (%s)-[%b]%u%c- %m'
# 
# Or you could add it as a new word, as in:
#
#     zstyle ':vcs_info:*' actionformats ' (%s)-[%b|%a]%u%c-' '%m'
#     zstyle ':vcs_info:*' formats ' (%s)-[%b]%u%c-' '%m'
#
# In the latter case, you will need to arrange to print ${vcs_info_msg_1_} in
# addition to ${vcs_info_msg_0_}; see the top of this file for details.


### Run vcs_info selectively to increase speed in large repos ################

# The following example shows a possible setup for vcs_info which displays
# staged and unstaged changes in the vcs_info prompt and prevents running
# it too often for speed reasons.


# Allow substitutions and expansions in the prompt, necessary for
# using a single-quoted $vcs_info_msg_0_ in PS1, RPOMPT (as used here) and
# similar. Other ways of using the information are described above.
setopt promptsubst
# Load vcs_info to display information about version control repositories.
autoload -Uz vcs_info

# Check the repository for changes so they can be used in %u/%c (see
# below). This comes with a speed penalty for bigger repositories.
zstyle ':vcs_info:*' check-for-changes true
zstyle ':vcs_info:*' get-revision true

# Alternatively, the following would set only %c, but is faster:
#zstyle ':vcs_info:*' check-for-changes false
#zstyle ':vcs_info:*' check-for-staged-changes true


# Default to running vcs_info. If possible we prevent running it later for
# speed reasons. If set to a non empty value vcs_info is run.
FORCE_RUN_VCS_INFO=1

# Only run vcs_info when necessary to speed up the prompt and make using
# check-for-changes bearable in bigger repositories. This setup was
# inspired by Bart Trojanowski
# (http://jukie.net/~bart/blog/pimping-out-zsh-prompt).
#
# This setup is by no means perfect. It can only detect changes done
# through the VCS's commands run by the current shell. If you use your
# editor to commit changes to the VCS or if you run them in another shell
# this setup won't detect them. To fix this just run "cd ." which causes
# vcs_info to run and update the information. If you use aliases to run
# the VCS commands update the case check below.
zstyle ':vcs_info:*+pre-get-data:*' hooks pre-get-data
+vi-pre-get-data() {
    # Only Git and Mercurial support and need caching. Abort if any other
    # VCS is used.
    [[ "$vcs" != git && "$vcs" != hg ]] && return

    # If the shell just started up or we changed directories (or for other
    # custom reasons) we must run vcs_info.
    if [[ -n $FORCE_RUN_VCS_INFO ]]; then
        FORCE_RUN_VCS_INFO=
        return
    fi

    # If we got to this point, running vcs_info was not forced, so now we
    # default to not running it and selectively choose when we want to run
    # it (ret=0 means run it, ret=1 means don't).
    ret=1
    # If a git/hg command was run then run vcs_info as the status might
    # need to be updated.
    case "$(fc -ln $(($HISTCMD-1)))" in
        git*)
            ret=0
            ;;
        hg*)
            ret=0
            ;;
    esac
}

# Call vcs_info as precmd before every prompt.
prompt_precmd() {
    vcs_info
}
add-zsh-hook precmd prompt_precmd

# Must run vcs_info when changing directories.
prompt_chpwd() {
    FORCE_RUN_VCS_INFO=1
}
add-zsh-hook chpwd prompt_chpwd

# Display the VCS information in the right prompt. The {..:- } is a
# workaround for Zsh below 4.3.9.
RPROMPT='${vcs_info_msg_0_:- }'


### Quilt support ############################################################

# Vcs_info does its best to support the patch management system quilt
# <http://savannah.nongnu.org/projects/quilt>. The information gathered by
# the quilt support always (and I'm saying always, because there are two
# ways quilt support can be active - see "man zshcontrib" for details)
# ends up in the `%Q' replacement in formats.
#
# Quilt support is also disabled by default. To turn its `addon' mode
# on for all backends, do:
zstyle ':vcs_info:*' use-quilt true

# Then use `%Q' somewhere in the `formats' and `actionformats' styles:
zstyle ':vcs_info:*' formats " (%s)-[%b%Q]-"
zstyle ':vcs_info:*' actionformats " (%s)-[%b%Q|%a]-"

# In the quilt support code, the zstyle context changes a little, it's now:
#       :vcs_info:<vcs>.quilt-<quiltmode>:*:*
# "<vcs>" is the version-control-system string and "<quiltmode>" is either
# `addon' or `standalone'. So, if you'd use quilt on top of CVS, the
# context becomes ":vcs_info:cvs.quilt-addon:*:*".

# That's almost all you need to know. Almost.
#
# Quilt support has a standalone mode. Even though quilt is not really
# a version control system, it keeps track of patches. It can work on top
# of a real VCS (like subversion or CVS - which is covered by addon mode)
# or apply patches to a normal directory tree that's not under version
# control. The debian project does this for a large number of packages,
# during their automatic build process.
# The `use-quilt' style only enables addon-mode, because for standalone
# mode we'd have to try to detect whether quilt is "active" in a directory.
# You can fine-tune that "detection" using the `quilt-standalone' style.
# If the value of that style is a function name, that function is executed
# without arguments to determine whether quilt-detection should be attempted.
# It's the most powerful way of doing this and we'll give a simple
# example later.

# First let's assume you want standalone mode to be active only in
# /usr/src/debian, ~/src/debian and their subdirectories. That's simple:

typeset -a foobar
foobar=(
    /usr/src/debian
    ~/src/debian
)
zstyle ':vcs_info:*' quilt-standalone foobar

# As mentioned earlier, using a function in this style is more powerful:
function foobar() {
    # You can do any sort of wicked wizardry here. This example just
    # checks if we're in "/usr/src/debian" or a subdirectory and if so
    # enables standalone detection.
    [[ $PWD == /usr/src/debian(|/*) ]] && return 0

    # Returning non-zero means false, which means don't enable the
    # "detection".
    return 1
}

# In standalone-mode, vcs_info pretends as if quilt actually was a VCS.
# Well, kind of. The vcs string is set to '-quilt-.quilt-standalone'. So let's
# define a format just for that mode:
zstyle ':vcs_info:-quilt-.quilt-standalone:*' formats " [%s%Q]-"

# As with other format insertions, you got total control over what is being
# inserted. The `%Q' insertion is controlled by the `quiltformat' and
# `quilt-nopatch-format' styles.

# quiltformat (default: "%p (%n applied)")
# The `%p' replacement tells you which patches are applied. `%n' tells you
# How many patches are applied. `%u' and `%N' do the same for unapplied patches.
#
# Now you might say, that's way too much. That'll eat up my entire screen if I
# all my 1002 patches applied. Well, true.
# By default, `%p' contains the top-most applied patch. `%u' says contains the
# number of unapplied patches and is therefore the same as `%c'.
# There are two hooks you can use to setup what these contain. Those would be
# `gen-applied-string' and `gen-unapplied-string'. We'll go with the default
# here... ...no need to go into every insane detail.
zstyle ':vcs_info:*' patch-format '#%p [%n|%c]'

# quilt-nopatch-format (default: "no patch applied")
zstyle ':vcs_info:*' nopatch-format '#cleeaaaaan!1!!'

# To retrieve information about unapplied patches, vcs_info invokes `quilt'
# itself. Even though that's pretty quick, it's not needed for the default
# behaviour. If we want to have `%c' and `%u' to contain meaningful data,
# we have to enable retrieval of unapplied data:
zstyle ':vcs_info:*' get-unapplied true

# With quilt, the location of its patches are configurable. It's either
# $QUILT_PATCHES or `patches' if that's unset. Let's assume we're a debian
# developer and want $QUILT_PATCHES to always be `debian/patches' in stand-
# alone mode:
zstyle ':vcs_info:-quilt-.quilt-standalone:*:*' quilt-patch-dir debian/patches

# Since we're a debian developer, we also have some packages of our own,
# 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>'.
#
# 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
# used as the value for the `quilt-patch-dir' style. We'll define the thing
# as a function - as the name suggests:

function my-patches-func() {
    local p
    # As the tidy debian developer we are, we're keeping our packages
    # in VCSs and they are located in one place `~/src/mypkgs/'
    if [[ $PWD == ${HOME}/src/mypkgs(|/*) ]]; then
        reply=( debian/patches )
        return 0
    fi

    # Now the part about the dedicated directory is a little trickier.
    # 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' 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
    fi

    # If we're here, there's something in $rrn, so:
    p="${HOME}/patches/${rrn}"
    if [[ ! -d $p ]]; then
        # ...and while we're at it, make sure it exists...
        mkdir -p "$p"
    fi
    reply=( $p )
}

# And finally, let's use the `post-quilt' hook to let vcs_info help us
# with setting the $QUILT_PATCHES variable. Since vcs_info already knows
# which $QUILT_PATCHES value is correct, it should just export that variable
# for us. No need to configure something twice when it can work
# automatically. :-)

# Register the hook:
zstyle ':vcs_info:*+post-quilt:*:*' hooks set-quilt-patches

# Define the corresponding function:
function +vi-set-quilt-patches() {
    # The `post-quilt' hook functions are called with three arguments:
    #   $1      the mode (`addon' vs. `standalone').
    #   $2      the path-name of the detected patches directory.
    #   $3      the path-name of the `.pc' directory (or "-nopc-" if it
    #           could not be found).
    # So, what we're after is in $2 already, which makes this function
    # rather trivial:
    export QUILT_PATCHES="$2"
    return 0
}

# This would take care of all the dedicated-patches-directory-in-${HOME}
# from earlier examples, too.

# Finally, the "Show information about patch series" example above this section
# may also be useful.


### Using vcs_info from CVS ##################################################

# You've decided you desperately need a newer feature of vcs_info than
# there is in your installed version of zsh.  That's possible, but be aware
# that you are choosing not only the newest features but potentially also
# the newest bugs of vcs_info. Also note, that vcs_info from CVS *may* rely
# on features of zsh that are only available in a newer version than you
# got installed on your system.
#
# So, now that the warnings are out of the way - let's cut to the chase:
# First you'll need to decide where to put the files from CVS. Many people
# keep a directory for personal function files such as `~/.zfuncs' or
# similar. That's what we'll use here.
#
# Step one: "get the thing from CVS"
#  % mkdir -p ~/.zfuncs
#  % cd ~/.zfuncs
#  % cvs -z3 -d:pserver:anonymous@zsh.cvs.sourceforge.net:/cvsroot/zsh \
#        co -d VCS_Info -PA zsh/Functions/VCS_Info
#
# There, now you got a `~/.zfuncs/VCS_Info' directory that has all the files
# you need. Whenever you feel like updating the checkout, you can do:
#  % cd ~/.zfuncs/VCS_Info; cvs up; cd -
#
# Step two: "Tell zsh to use the checkout"
# Zsh looks for function files in the directories listed in $fpath. If
# you're already using `~/.zfuncs' you probably have something like this
# in your setup:

fpath=( ~/.zfuncs $fpath )

# Note, that the private directory is added in *front* of the default
# value, so that files from that directory supersede the ones from system
# directories. To add the VCS_Info subtree (excluding the CVS directories)
# in front, change that line to this:

fpath=( ~/.zfuncs ~/.zfuncs/VCS_Info/**/*~*/(CVS)#(/) $fpath )

# The weirdly looking pattern requires the `extended_glob' option to be
# active, so make sure it is.
#
# Step three: "Restart Z shell"
# A simple
#  % exec zsh
# gets you there. You should be all set now. Have fun.