From 07ab4dec80f1c24660ed4bc371849fb4f11a4ee3 Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Wed, 16 Jan 2013 08:51:57 +0100 Subject: config: Introduce diff.algorithm variable Some users or projects prefer different algorithms over others, e.g. patience over myers or similar. However, specifying appropriate argument every time diff is to be used is impractical. Moreover, creating an alias doesn't play nicely with other tools based on diff (git-show for instance). Hence, a configuration variable which is able to set specific algorithm is needed. For now, these four values are accepted: 'myers' (which has the same effect as not setting the config variable at all), 'minimal', 'patience' and 'histogram'. Signed-off-by: Michal Privoznik Signed-off-by: Junio C Hamano --- diff.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'diff.c') diff --git a/diff.c b/diff.c index 732d4c2275..d2be777793 100644 --- a/diff.c +++ b/diff.c @@ -36,6 +36,7 @@ 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 long diff_algorithm; static char diff_colors[][COLOR_MAXLEN] = { GIT_COLOR_RESET, @@ -143,6 +144,21 @@ static int git_config_rename(const char *var, const char *value) return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0; } +static long parse_algorithm_value(const char *value) +{ + if (!value) + return -1; + else if (!strcasecmp(value, "myers") || !strcasecmp(value, "default")) + return 0; + else if (!strcasecmp(value, "minimal")) + return XDF_NEED_MINIMAL; + else if (!strcasecmp(value, "patience")) + return XDF_PATIENCE_DIFF; + else if (!strcasecmp(value, "histogram")) + return XDF_HISTOGRAM_DIFF; + return -1; +} + /* * These are to give UI layer defaults. * The core-level commands such as git-diff-files should @@ -196,6 +212,13 @@ int git_diff_ui_config(const char *var, const char *value, void *cb) return 0; } + if (!strcmp(var, "diff.algorithm")) { + diff_algorithm = parse_algorithm_value(value); + if (diff_algorithm < 0) + return -1; + return 0; + } + if (git_color_config(var, value, cb) < 0) return -1; @@ -3213,6 +3236,7 @@ void diff_setup(struct diff_options *options) options->add_remove = diff_addremove; options->use_color = diff_use_color_default; options->detect_rename = diff_detect_rename_default; + options->xdl_opts |= diff_algorithm; if (diff_no_prefix) { options->a_prefix = options->b_prefix = ""; -- cgit v1.2.3 From 07924d4d50e5304fb53eb60aaba8aef31d4c4e5e Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Wed, 16 Jan 2013 08:51:58 +0100 Subject: diff: Introduce --diff-algorithm command line option Since command line options have higher priority than config file variables and taking previous commit into account, we need a way how to specify myers algorithm on command line. However, inventing `--myers` is not the right answer. We need far more general option, and that is `--diff-algorithm`. Signed-off-by: Michal Privoznik Signed-off-by: Junio C Hamano --- Documentation/diff-options.txt | 20 ++++++++++++++++++++ contrib/completion/git-completion.bash | 11 +++++++++++ diff.c | 12 +++++++++++- diff.h | 2 ++ merge-recursive.c | 9 +++++++++ 5 files changed, 53 insertions(+), 1 deletion(-) (limited to 'diff.c') diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index 39f2c5074c..81e5be13da 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -55,6 +55,26 @@ endif::git-format-patch[] --histogram:: Generate a diff using the "histogram diff" algorithm. +--diff-algorithm={patience|minimal|histogram|myers}:: + Choose a diff algorithm. The variants are as follows: ++ +-- +`default`, `myers`;; + The basic greedy diff algorithm. Currently, this is the default. +`minimal`;; + Spend extra time to make sure the smallest possible diff is + produced. +`patience`;; + Use "patience diff" algorithm when generating patches. +`histogram`;; + This algorithm extends the patience algorithm to "support + low-occurrence common elements". +-- ++ +For instance, if you configured diff.algorithm variable to a +non-default value and want to use the default one, then you +have to use `--diff-algorithm=default` option. + --stat[=[,[,]]]:: 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 33e25dc08c..d592cf9be9 100644 --- a/contrib/completion/git-completion.bash +++ b/contrib/completion/git-completion.bash @@ -1021,6 +1021,8 @@ _git_describe () __gitcomp_nl "$(__git_refs)" } +__git_diff_algorithms="myers minimal patience histogram" + __git_diff_common_options="--stat --numstat --shortstat --summary --patch-with-stat --name-only --name-status --color --no-color --color-words --no-renames --check @@ -1035,6 +1037,7 @@ __git_diff_common_options="--stat --numstat --shortstat --summary --raw --dirstat --dirstat= --dirstat-by-file --dirstat-by-file= --cumulative + --diff-algorithm= " _git_diff () @@ -1042,6 +1045,10 @@ _git_diff () __git_has_doubledash && return case "$cur" in + --diff-algorithm=*) + __gitcomp "$__git_diff_algorithms" "" "${cur##--diff-algorithm=}" + return + ;; --*) __gitcomp "--cached --staged --pickaxe-all --pickaxe-regex --base --ours --theirs --no-index @@ -2114,6 +2121,10 @@ _git_show () " "" "${cur#*=}" return ;; + --diff-algorithm=*) + __gitcomp "$__git_diff_algorithms" "" "${cur##--diff-algorithm=}" + return + ;; --*) __gitcomp "--pretty= --format= --abbrev-commit --oneline $__git_diff_common_options diff --git a/diff.c b/diff.c index d2be777793..0724fa6ff6 100644 --- a/diff.c +++ b/diff.c @@ -144,7 +144,7 @@ static int git_config_rename(const char *var, const char *value) return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0; } -static long parse_algorithm_value(const char *value) +long parse_algorithm_value(const char *value) { if (!value) return -1; @@ -3634,6 +3634,16 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac) options->xdl_opts = DIFF_WITH_ALG(options, PATIENCE_DIFF); else if (!strcmp(arg, "--histogram")) options->xdl_opts = DIFF_WITH_ALG(options, HISTOGRAM_DIFF); + else if (!prefixcmp(arg, "--diff-algorithm=")) { + long value = parse_algorithm_value(arg+17); + if (value < 0) + return error("option diff-algorithm accepts \"myers\", " + "\"minimal\", \"patience\" and \"histogram\""); + /* clear out previous settings */ + DIFF_XDL_CLR(options, NEED_MINIMAL); + options->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK; + options->xdl_opts |= value; + } /* flags options */ else if (!strcmp(arg, "--binary")) { diff --git a/diff.h b/diff.h index a47bae48d5..54c2590b4f 100644 --- a/diff.h +++ b/diff.h @@ -333,6 +333,8 @@ extern struct userdiff_driver *get_textconv(struct diff_filespec *one); extern int parse_rename_score(const char **cp_p); +extern long parse_algorithm_value(const char *value); + extern int print_stat_summary(FILE *fp, int files, int insertions, int deletions); extern void setup_diff_pager(struct diff_options *); diff --git a/merge-recursive.c b/merge-recursive.c index 33ba5dc07c..ea9dbd307c 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -2068,6 +2068,15 @@ int parse_merge_opt(struct merge_options *o, const char *s) o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF); else if (!strcmp(s, "histogram")) o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF); + else if (!strcmp(s, "diff-algorithm=")) { + long value = parse_algorithm_value(s+15); + if (value < 0) + return -1; + /* clear out previous settings */ + DIFF_XDL_CLR(o, NEED_MINIMAL); + o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK; + o->xdl_opts |= value; + } else if (!strcmp(s, "ignore-space-change")) o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE; else if (!strcmp(s, "ignore-all-space")) -- cgit v1.2.3