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>]
  13--
  14j=n     parallel argument to pass to make
  15f       force rebuild; do not rely on cached results
  16"
  17SUBDIRECTORY_OK=1
  18. "$(git --exec-path)/git-sh-setup"
  19
  20parallel=
  21force=
  22while test $# -gt 0
  23do
  24        case "$1" in
  25        -j)
  26                parallel=$2; shift ;;
  27        -f)
  28                force=t ;;
  29        --)
  30                shift; break ;;
  31        *)
  32                usage ;;
  33        esac
  34        shift
  35done
  36
  37if test -z "$parallel"
  38then
  39        parallel=$(getconf _NPROCESSORS_ONLN 2>/dev/null)
  40        if test $? != 0 || test -z "$parallel"
  41        then
  42                parallel=1
  43        fi
  44fi
  45
  46test $# -gt 1 || usage
  47from=$1; shift
  48to=$1; shift
  49
  50from_oid=$(git rev-parse --verify "$from") || exit 1
  51to_oid=$(git rev-parse --verify "$to") || exit 1
  52
  53cd_to_toplevel
  54tmp=Documentation/tmp-doc-diff
  55
  56if test -n "$force"
  57then
  58        rm -rf "$tmp"
  59fi
  60
  61# We'll do both builds in a single worktree, which lets "make" reuse
  62# results that don't differ between the two trees.
  63if ! test -d "$tmp/worktree"
  64then
  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"
  68fi
  69
  70# generate_render_makefile <srcdir> <dstdir>
  71generate_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 $@+ $@\n'
  82        done
  83}
  84
  85# render_tree <committish_oid>
  86render_tree () {
  87        # Skip install-man entirely if we already have an installed directory.
  88        # We can't rely on make here, since "install-man" unconditionally
  89        # copies the files (spending effort, but also updating timestamps that
  90        # we then can't rely on during the render step). We use "mv" to make
  91        # sure we don't get confused by a previous run that failed partway
  92        # through.
  93        if ! test -d "$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
 115render_tree $from_oid &&
 116render_tree $to_oid &&
 117git -C $tmp/rendered diff --no-index "$@" $from_oid $to_oid