Michal PrivoznikSome users have preference over various diff algorithms. However, now they are forced to use appropriate argument every time they run git-diff and tools using it. This is impractical. Therefore create new variable which can set preferred algorithm. Of course, this can be overridden on command line via --diff-algorithm=*. Accepted values are myers (default), histogram, minimal, patience.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- This is basically v2 for:
http://www.spinics.net/lists/git/msg176100.html
As we agreed on list, I've switched from diff.patience to diff.algorithm and created new argument --diff-algorithm.
Please keep me CC'ed as I am not signed into the list.
Documentation/diff-config.txt | 21 +++++++++++++++++++ Documentation/diff-options.txt | 23 +++++++++++++++++++++ contrib/completion/git-completion.bash | 13 +++++++++++ diff.c | 35 ++++++++++++++++++++++++++++++++ 4 files changed, 92 insertions(+), 0 deletions(-)
Show changes to 4 files +92 −0
Documentation/diff-config.txt, Documentation/diff-options.txt, contrib/completion/git-completion.bash, diff.c
diff --git a/Documentation/diff-config.txt b/Documentation/diff-config.txt index 6aa1be0..1047e81 100644 --- a/Documentation/diff-config.txt +++ b/Documentation/diff-config.txt @@ -1,3 +1,24 @@ +diff.algorithm:: + Choose a diff algorithm. The variants are as follows: ++ +-- +histogram:: + This is the fastest algorithm. + +myers:: + The classical Myers diff algorithm. This is the default. + +minimal:: + Like 'myers', but spend extra time making sure that the diff + is the shortest possible for the set of changes performed. + +patience:: + The patience diff algorithm, which first matches unique lines + with each other. This sometimes results in more readable (if + longer) patches than the other algorithms. +-- ++ + diff.autorefreshindex:: When using 'git diff' to compare with work tree files, do not consider stat-only change as changed. diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index 7d4566f..4e8bc5b 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -55,6 +55,29 @@ endif::git-format-patch[] --histogram:: Generate a diff using the "histogram diff" algorithm. +--diff-algorithm={histogram|myers|minimal|patience}:: + Choose a diff algorithm. The defaults are controlled + by the `diff.algorithm` configuration variable + (see linkgit:git-config[1]). The variants are as follows: ++ +-- +histogram:: + This is the fastest algorithm. + +myers:: + The classical Myers diff algorithm. This is the default. + +minimal:: + Like 'myers', but spend extra time making sure that the diff + is the shortest possible for the set of changes performed. + +patience:: + The patience diff algorithm, which first matches unique lines + with each other. This sometimes results in more readable (if + longer) patches than the other algorithms. +-- ++ + --stat[=<width>[,<name-width>[,<count>]]]:: Generate a diffstat. By default, as much space as necessary will be used for the filename part, and the rest for the graph diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash index fba076d..d54f3a3 100755 --- a/contrib/completion/git-completion.bash +++ b/contrib/completion/git-completion.bash @@ -1299,6 +1299,7 @@ __git_diff_common_options="--stat --numstat --shortstat --summary --raw --dirstat --dirstat= --dirstat-by-file --dirstat-by-file= --cumulative + --diff-algorithm= " _git_diff () @@ -1306,6 +1307,10 @@ _git_diff () __git_has_doubledash && return case "$cur" in + --diff-algorithm=*) + __gitcomp "myers histogram minimal patience" + return + ;; --*) __gitcomp "--cached --staged --pickaxe-all --pickaxe-regex --base --ours --theirs --no-index @@ -1569,6 +1574,10 @@ _git_log () __gitcomp "long short" "" "${cur##--decorate=}" return ;; + --diff-algorithm=*) + __gitcomp "myers histogram minimal patience" + return + ;; --*) __gitcomp " $__git_log_common_options @@ -2376,6 +2385,10 @@ _git_show () " "" "${cur#*=}" return ;; + --diff-algorithm=*) + __gitcomp "myers histogram minimal patience" + return + ;; --*) __gitcomp "--pretty= --format= --abbrev-commit --oneline $__git_diff_common_options diff --git a/diff.c b/diff.c index 377ec1e..f5c965b 100644 --- a/diff.c +++ b/diff.c @@ -34,6 +34,7 @@ static int diff_no_prefix; static int diff_stat_graph_width; static int diff_dirstat_permille_default = 30; static struct diff_options default_diff_options; +static int diff_algorithm = 0; static char diff_colors[][COLOR_MAXLEN] = { GIT_COLOR_RESET, @@ -47,6 +48,20 @@ static char diff_colors[][COLOR_MAXLEN] = { GIT_COLOR_NORMAL, /* FUNCINFO */ }; +static int diff_algorithm_parse(const char *alg) +{ + if (!alg || !strcmp(alg, "myers")) + return 0; + else if (!strcmp(alg, "patience")) + return XDF_PATIENCE_DIFF; + else if (!strcmp(alg, "histogram")) + return XDF_HISTOGRAM_DIFF; + else if (!strcmp(alg, "minimal")) + return XDF_NEED_MINIMAL; + + return -1; +} + static int parse_diff_color_slot(const char *var, int ofs) { if (!strcasecmp(var+ofs, "plain")) @@ -169,6 +184,12 @@ int git_diff_ui_config(const char *var, const char *value, void *cb) if (!strcmp(var, "diff.ignoresubmodules")) handle_ignore_submodules_arg(&default_diff_options, value); + if (!strcmp(var, "diff.algorithm")) { + if ((diff_algorithm = diff_algorithm_parse(value)) < 0) + die("bad diff.algorithm value: %s", value); + return 0; + } + if (git_color_config(var, value, cb) < 0) return -1; @@ -3250,6 +3271,9 @@ int diff_setup_done(struct diff_options *options) DIFF_OPT_SET(options, EXIT_WITH_STATUS); } + /* set diff algorithm */ + options->xdl_opts |= diff_algorithm; + return 0; } @@ -3528,6 +3552,17 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac) DIFF_XDL_SET(options, PATIENCE_DIFF); else if (!strcmp(arg, "--histogram")) DIFF_XDL_SET(options, HISTOGRAM_DIFF); + else if ((argcount = parse_long_opt("diff-algorithm", av, &optarg))) { + int alg = diff_algorithm_parse(optarg); + if (alg < 0) + die("unknown algorithm: %s", optarg); + DIFF_XDL_CLR(options, NEED_MINIMAL); + DIFF_XDL_CLR(options, HISTOGRAM_DIFF); + DIFF_XDL_CLR(options, PATIENCE_DIFF); + options->xdl_opts |= alg; + return argcount; + } + /* flags options */ else if (!strcmp(arg, "--binary")) {
-- 1.7.8.5
