@@ -634,7 +634,8 @@ Writing Documentation:
A few commented examples follow to provide reference when writing or
modifying command usage strings and synopsis sections in the manual
- pages:
+ pages. The two should match, see t/t0450-txt-doc-vs-help.sh for
+ (partial) regression testing.
Placeholders are spelled in lowercase and enclosed in angle brackets:
<file>
new file mode 100755
@@ -0,0 +1,184 @@
+#!/bin/sh
+
+test_description='compare (unbuilt) Documentation/*.txt to -h output
+
+Run this with --debug to see a summary of where we still fail to make
+the two versions consistent with one another.'
+
+. ./test-lib.sh
+
+test_expect_success 'setup: list of builtins' '
+ git --list-cmds=builtins >builtins
+'
+
+test_expect_success 'setup: list of txt v.s. help' '
+ cat >list <<-\EOF
+ add
+ am
+ apply
+ archive
+ bisect
+ blame
+ branch
+ check-ref-format
+ checkout
+ checkout-index
+ clone
+ column
+ config
+ credential
+ credential-cache
+ credential-store
+ fast-export
+ fast-import
+ fetch-pack
+ fmt-merge-msg
+ for-each-ref
+ format-patch
+ fsck-objects
+ fsmonitor--daemon
+ gc
+ grep
+ index-pack
+ init-db
+ log
+ ls-files
+ ls-tree
+ mailinfo
+ mailsplit
+ maintenance
+ merge
+ merge-file
+ merge-index
+ merge-one-file
+ multi-pack-index
+ name-rev
+ notes
+ pack-objects
+ push
+ range-diff
+ rebase
+ remote
+ remote-ext
+ remote-fd
+ repack
+ reset
+ restore
+ rev-parse
+ show
+ stage
+ switch
+ update-index
+ update-ref
+ whatchanged
+ EOF
+'
+
+test_expect_success 'setup: list of txt v.s. help is sorted' '
+ sort -u list >list.sorted &&
+ if ! test_cmp list list.sorted
+ then
+ BUG "please keep the command list sorted"
+ fi
+'
+
+builtin_to_synopsis () {
+ builtin="$1" &&
+ test_when_finished "rm -f out" &&
+ test_expect_code 129 git $builtin -h >out 2>&1 &&
+ sed -n \
+ -e '1,/^$/ {
+ /^$/d;
+ s/^usage: //;
+ s/^ *or: //;
+ p;
+ }' <out
+}
+
+builtin_to_txt () {
+ echo "$GIT_BUILD_DIR/Documentation/git-$1.txt"
+}
+
+txt_synopsis () {
+ sed -n \
+ -e '/^\[verse\]$/,/^$/ {
+ /^$/d;
+ /^\[verse\]$/d;
+ s/{litdd}/--/g;
+
+ s/'\''\(git[ a-z-]*\)'\''/\1/g;
+ p;
+ }' \
+ <"$1"
+}
+
+HT=" "
+align_after_nl () {
+ builtin="$1" &&
+ len=$(printf "git %s " "$builtin" | wc -c) &&
+ pad=$(printf "%${len}s" "") &&
+
+ sed "s/^[ $HT][ $HT]*/$pad/"
+}
+
+test_debug '>failing'
+while read builtin
+do
+ test_expect_success "$builtin -h output has no \t" '
+ builtin_to_synopsis "$builtin" >help.raw &&
+ ! grep "$HT" help.raw
+ '
+
+ txt="$(builtin_to_txt "$builtin")" &&
+ preq="$(echo BUILTIN_TXT_$builtin | tr '[:lower:]-' '[:upper:]_')" &&
+
+ if test -f "$txt"
+ then
+ test_set_prereq "$preq"
+ fi &&
+
+ result=
+ if grep -q "^$builtin$" list
+ then
+ result=failure
+ else
+ result=success
+ fi &&
+
+ test_expect_$result "$preq" "$builtin -h output and SYNOPSIS agree" '
+ txt_synopsis "$txt" >txt.raw &&
+ if test "$builtin" = "merge-tree"
+ then
+ sed -e '\''s/ (deprecated)$//g'\'' <txt.raw >txt.raw.new &&
+ mv txt.raw.new txt.raw
+ fi &&
+ builtin_to_synopsis "$builtin" >help.raw &&
+
+ # The *.txt and -h use different spacing for the
+ # alignment of continued usage output, normalize it.
+ align_after_nl "$builtin" <txt.raw >txt &&
+ align_after_nl "$builtin" <help.raw >help &&
+ test_cmp txt help
+ '
+
+ if test_have_prereq "$preq" && test -e txt && test -e help
+ then
+ test_debug '
+ if test_cmp txt help >cmp 2>/dev/null
+ then
+ echo "=== DONE: $builtin ==="
+ else
+ echo "=== TODO: $builtin ===" &&
+ cat cmp
+ fi >>failing
+ '
+
+ # Not in test_expect_success in case --run is being
+ # used with --debug
+ rm -f txt help tmp 2>/dev/null
+ fi
+done <builtins
+
+test_debug 'say "$(cat failing)"'
+
+test_done
There's been a lot of incremental effort to make the SYNOPSIS output in our documentation consistent with the -h output, e.g. cbe485298bf (git reflog [expire|delete]: make -h output consistent with SYNOPSIS, 2022-03-17) is one recent example, but that effort has been an uphill battle due to the lack of regression testing. This adds such regression testing, we can parse out the SYNOPSIS output with "sed", and is turns out it's relatively easy to normalize it and the "-h" output to match on another. We now ensure that we won't have regressions when it comes to the list of commands in "expect_help_to_match_txt" below, and in subsequent commits we'll make more of them consistent. The naïve parser here gets quite a few things wrong, but it doesn't need to be perfect, just good enough that we can compare /some/ of this help output. There's no cases where the output would match except for the parser's stupidity, it's all cases of e.g. comparing the *.txt to non-parse_options() output. Since that output is wildly different than the *.txt anyway let's leave this for now, we can fix the parser some other time, or it won't become necessary as we'll e.g. convert more things to using parse_options(). Having a special-case for "merge-tree"'s 1f0c3a29da3 (merge-tree: implement real merges, 2022-06-18) is a bit ugly, but preferred to blessing that " (deprecated)" pattern for other commands. We'd probably want to add some other way of marking deprecated commands in the SYNOPSIS syntax. Syntactically 1f0c3a29da3's way of doing it is indistinguishable from the command taking an optional literal "deprecated" string as an argument. Some of the issues that are left: * "git show -h", "git whatchanged -h" and "git reflog --oneline -h" all showing "git log" and "git show" usage output. I.e. the "builtin_log_usage" in builtin/log.c doesn't take into account what command we're running. * Likewise "git stage -h" shows "git add" usage, but should be aware of what command it's running. The same for "annotate" and "blame". * Commands which implement subcommands such as like "multi-pack-index", "notes", "remote" etc. having their subcommands in a very different order in the *.txt and *.c. Fixing it would require some verbose diffs, so it's been left alone for onw. * Commands such as "format-patch" have a very long argument list in the *.txt, but just "[<options>]" in the *.c. What to do about these has been left out of this series, except to the extent that preceding commits changed "[<options>]" (or equivalent) to the list of options in cases where that list of options was tiny, or we clearly meant to exhaustively list the options in both *.txt and *.c. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- Documentation/CodingGuidelines | 3 +- t/t0450-txt-doc-vs-help.sh | 184 +++++++++++++++++++++++++++++++++ 2 files changed, 186 insertions(+), 1 deletion(-) create mode 100755 t/t0450-txt-doc-vs-help.sh