summaryrefslogtreecommitdiff
path: root/Documentation/doc-diff
diff options
context:
space:
mode:
authorLibravatar Jeff King <peff@peff.net>2018-08-06 13:37:20 -0400
committerLibravatar Junio C Hamano <gitster@pobox.com>2018-08-06 12:30:23 -0700
commitbeb188e22ad0ca4287984c316c7e0b0f9aa895e6 (patch)
tree3e9673591b2e7dd27cd1392345ab6bc7ab261163 /Documentation/doc-diff
parentFifth batch for 2.19 cycle (diff)
downloadtgif-beb188e22ad0ca4287984c316c7e0b0f9aa895e6.tar.xz
add a script to diff rendered documentation
After making a change to the documentation, it's easy to forget to check the rendered version to make sure it was formatted as you intended. And simply doing a diff between the two built versions is less trivial than you might hope: - diffing the roff or html output isn't particularly readable; what we really care about is what the end user will see - you have to tweak a few build variables to avoid spurious differences (e.g., version numbers, build times) Let's provide a script that builds and installs the manpages for two commits, renders the results using "man", and diffs the result. Since this is time-consuming, we'll also do our best to avoid repeated work, keeping intermediate results between runs. Some of this could probably be made a little less ugly if we built support into Documentation/Makefile. But by relying only on "make install-man" working, this script should work for generating a diff between any two versions, whether they include this script or not. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'Documentation/doc-diff')
-rwxr-xr-xDocumentation/doc-diff109
1 files changed, 109 insertions, 0 deletions
diff --git a/Documentation/doc-diff b/Documentation/doc-diff
new file mode 100755
index 0000000000..f483fe427c
--- /dev/null
+++ b/Documentation/doc-diff
@@ -0,0 +1,109 @@
+#!/bin/sh
+
+OPTIONS_SPEC="\
+doc-diff [options] <from> <to> [-- <diff-options>]
+--
+j=n parallel argument to pass to make
+f force rebuild; do not rely on cached results
+"
+SUBDIRECTORY_OK=1
+. "$(git --exec-path)/git-sh-setup"
+
+parallel=
+force=
+while test $# -gt 0
+do
+ case "$1" in
+ -j)
+ parallel=$2; shift ;;
+ -f)
+ force=t ;;
+ --)
+ shift; break ;;
+ *)
+ usage ;;
+ esac
+ shift
+done
+
+if test -z "$parallel"
+then
+ parallel=$(getconf _NPROCESSORS_ONLN 2>/dev/null)
+ if test $? != 0 || test -z "$parallel"
+ then
+ parallel=1
+ fi
+fi
+
+test $# -gt 1 || usage
+from=$1; shift
+to=$1; shift
+
+from_oid=$(git rev-parse --verify "$from") || exit 1
+to_oid=$(git rev-parse --verify "$to") || exit 1
+
+cd_to_toplevel
+tmp=Documentation/tmp-doc-diff
+
+if test -n "$force"
+then
+ rm -rf "$tmp"
+fi
+
+# We'll do both builds in a single worktree, which lets "make" reuse
+# results that don't differ between the two trees.
+if ! test -d "$tmp/worktree"
+then
+ git worktree add --detach "$tmp/worktree" "$from" &&
+ dots=$(echo "$tmp/worktree" | sed 's#[^/]*#..#g') &&
+ ln -s "$dots/config.mak" "$tmp/worktree/config.mak"
+fi
+
+# generate_render_makefile <srcdir> <dstdir>
+generate_render_makefile () {
+ find "$1" -type f |
+ while read src
+ do
+ dst=$2/${src#$1/}
+ printf 'all:: %s\n' "$dst"
+ printf '%s: %s\n' "$dst" "$src"
+ printf '\t@echo >&2 " RENDER $(notdir $@)" && \\\n'
+ printf '\tmkdir -p $(dir $@) && \\\n'
+ printf '\tMANWIDTH=80 man -l $< >$@+ && \\\n'
+ printf '\tmv $@+ $@\n'
+ done
+}
+
+# render_tree <dirname> <committish>
+render_tree () {
+ # Skip install-man entirely if we already have an installed directory.
+ # We can't rely on make here, since "install-man" unconditionally
+ # copies the files (spending effort, but also updating timestamps that
+ # we then can't rely on during the render step). We use "mv" to make
+ # sure we don't get confused by a previous run that failed partway
+ # through.
+ if ! test -d "$tmp/installed/$1"
+ then
+ git -C "$tmp/worktree" checkout "$2" &&
+ make -j$parallel -C "$tmp/worktree" \
+ GIT_VERSION=omitted \
+ SOURCE_DATE_EPOCH=0 \
+ DESTDIR="$PWD/$tmp/installed/$1+" \
+ install-man &&
+ mv "$tmp/installed/$1+" "$tmp/installed/$1"
+ fi &&
+
+ # As with "installed" above, we skip the render if it's already been
+ # done. So using make here is primarily just about running in
+ # parallel.
+ if ! test -d "$tmp/rendered/$1"
+ then
+ generate_render_makefile "$tmp/installed/$1" "$tmp/rendered/$1+" |
+ make -j$parallel -f - &&
+ mv "$tmp/rendered/$1+" "$tmp/rendered/$1"
+ fi
+}
+
+render_tree $from_oid "$from" &&
+render_tree $to_oid "$to" &&
+git -C $tmp/rendered diff --no-index "$@" $from_oid $to_oid