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