Andrew's git - gitweb.git/blob - Documentation/doc-diff

   1#!/bin/sh
   2#
   3# Build two documentation trees and diff the resulting formatted output.
   4# Compared to a source diff, this can reveal mistakes in the formatting.
   5# For example:
   6#
   7#   ./doc-diff origin/master HEAD
   8#
   9# would show the differences introduced by a branch based on master.
  10
  11OPTIONS_SPEC="\
  12doc-diff [options] <from> <to> [-- <diff-options>]
  13doc-diff (-c|--clean)
  14--
  15j=n     parallel argument to pass to make
  16f       force rebuild; do not rely on cached results
  17c,clean cleanup temporary working files
  18"
  19SUBDIRECTORY_OK=1
  20. "$(git --exec-path)/git-sh-setup"
  21
  22parallel=
  23force=
  24clean=
  25while test $# -gt 0
  26do
  27        case "$1" in
  28        -j)
  29                parallel=$2; shift ;;
  30        -c|--clean)
  31                clean=t ;;
  32        -f)
  33                force=t ;;
  34        --)
  35                shift; break ;;
  36        *)
  37                usage ;;
  38        esac
  39        shift
  40done
  41
  42tmp="$(git rev-parse --show-toplevel)/Documentation/tmp-doc-diff" || exit 1
  43
  44if test -n "$clean"
  45then
  46        test $# -eq 0 || usage
  47        git worktree remove --force "$tmp/worktree" 2>/dev/null
  48        rm -rf "$tmp"
  49        exit 0
  50fi
  51
  52if test -z "$parallel"
  53then
  54        parallel=$(getconf _NPROCESSORS_ONLN 2>/dev/null)
  55        if test $? != 0 || test -z "$parallel"
  56        then
  57                parallel=1
  58        fi
  59fi
  60
  61test $# -gt 1 || usage
  62from=$1; shift
  63to=$1; shift
  64
  65from_oid=$(git rev-parse --verify "$from") || exit 1
  66to_oid=$(git rev-parse --verify "$to") || exit 1
  67
  68if test -n "$force"
  69then
  70        rm -rf "$tmp"
  71fi
  72
  73# We'll do both builds in a single worktree, which lets "make" reuse
  74# results that don't differ between the two trees.
  75if ! test -d "$tmp/worktree"
  76then
  77        git worktree add -f --detach "$tmp/worktree" "$from" &&
  78        dots=$(echo "$tmp/worktree" | sed 's#[^/]*#..#g') &&
  79        ln -s "$dots/config.mak" "$tmp/worktree/config.mak"
  80fi
  81
  82# generate_render_makefile <srcdir> <dstdir>
  83generate_render_makefile () {
  84        find "$1" -type f |
  85        while read src
  86        do
  87                dst=$2/${src#$1/}
  88                printf 'all:: %s\n' "$dst"
  89                printf '%s: %s\n' "$dst" "$src"
  90                printf '\t@echo >&2 "  RENDER $(notdir $@)" && \\\n'
  91                printf '\tmkdir -p $(dir $@) && \\\n'
  92                printf '\tMANWIDTH=80 man $< >$@+ && \\\n'
  93                printf '\tmv $@+ $@\n'
  94        done
  95}
  96
  97# render_tree <committish_oid>
  98render_tree () {
  99        # Skip install-man entirely if we already have an installed directory.
 100        # We can't rely on make here, since "install-man" unconditionally
 101        # copies the files (spending effort, but also updating timestamps that
 102        # we then can't rely on during the render step). We use "mv" to make
 103        # sure we don't get confused by a previous run that failed partway
 104        # through.
 105        if ! test -d "$tmp/installed/$1"
 106        then
 107                git -C "$tmp/worktree" checkout --detach "$1" &&
 108                make -j$parallel -C "$tmp/worktree" \
 109                        GIT_VERSION=omitted \
 110                        SOURCE_DATE_EPOCH=0 \
 111                        DESTDIR="$tmp/installed/$1+" \
 112                        install-man &&
 113                mv "$tmp/installed/$1+" "$tmp/installed/$1"
 114        fi &&
 115
 116        # As with "installed" above, we skip the render if it's already been
 117        # done.  So using make here is primarily just about running in
 118        # parallel.
 119        if ! test -d "$tmp/rendered/$1"
 120        then
 121                generate_render_makefile "$tmp/installed/$1" "$tmp/rendered/$1+" |
 122                make -j$parallel -f - &&
 123                mv "$tmp/rendered/$1+" "$tmp/rendered/$1"
 124        fi
 125}
 126
 127render_tree $from_oid &&
 128render_tree $to_oid &&
 129git -C $tmp/rendered diff --no-index "$@" $from_oid $to_oid