diff options
| -rw-r--r-- | Documentation/gitattributes.txt | 31 | ||||
| -rw-r--r-- | diff.c | 90 | ||||
| -rw-r--r-- | diff.h | 1 | ||||
| -rw-r--r-- | t/lib-diff-alternative.sh | 38 | ||||
| -rw-r--r-- | userdiff.c | 4 | ||||
| -rw-r--r-- | userdiff.h | 1 |
6 files changed, 140 insertions, 25 deletions
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index c19e64ea0e..39bfbca1ff 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -758,6 +758,37 @@ with the above configuration, i.e. `j-c-diff`, with 7 parameters, just like `GIT_EXTERNAL_DIFF` program is called. See linkgit:git[1] for details. +Setting the internal diff algorithm +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The diff algorithm can be set through the `diff.algorithm` config key, but +sometimes it may be helpful to set the diff algorithm per path. For example, +one may want to use the `minimal` diff algorithm for .json files, and the +`histogram` for .c files, and so on without having to pass in the algorithm +through the command line each time. + +First, in `.gitattributes`, assign the `diff` attribute for paths. + +------------------------ +*.json diff=<name> +------------------------ + +Then, define a "diff.<name>.algorithm" configuration to specify the diff +algorithm, choosing from `myers`, `patience`, `minimal`, or `histogram`. + +---------------------------------------------------------------- +[diff "<name>"] + algorithm = histogram +---------------------------------------------------------------- + +This diff algorithm applies to user facing diff output like git-diff(1), +git-show(1) and is used for the `--stat` output as well. The merge machinery +will not use the diff algorithm set through this method. + +NOTE: If `diff.<name>.command` is defined for path with the +`diff=<name>` attribute, it is executed as an external diff driver +(see above), and adding `diff.<name>.algorithm` has no effect, as the +algorithm is not passed to the external diff driver. Defining a custom hunk-header ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -3437,6 +3437,22 @@ static int diff_filepair_is_phoney(struct diff_filespec *one, return !DIFF_FILE_VALID(one) && !DIFF_FILE_VALID(two); } +static int set_diff_algorithm(struct diff_options *opts, + const char *alg) +{ + long value = parse_algorithm_value(alg); + + if (value < 0) + return -1; + + /* clear out previous settings */ + DIFF_XDL_CLR(opts, NEED_MINIMAL); + opts->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK; + opts->xdl_opts |= value; + + return 0; +} + static void builtin_diff(const char *name_a, const char *name_b, struct diff_filespec *one, @@ -4440,15 +4456,13 @@ static void run_diff_cmd(const char *pgm, const char *xfrm_msg = NULL; int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score; int must_show_header = 0; + struct userdiff_driver *drv = NULL; - - if (o->flags.allow_external) { - struct userdiff_driver *drv; - + if (o->flags.allow_external || !o->ignore_driver_algorithm) drv = userdiff_find_by_path(o->repo->index, attr_path); - if (drv && drv->external) - pgm = drv->external; - } + + if (o->flags.allow_external && drv && drv->external) + pgm = drv->external; if (msg) { /* @@ -4465,12 +4479,16 @@ static void run_diff_cmd(const char *pgm, run_external_diff(pgm, name, other, one, two, xfrm_msg, o); return; } - if (one && two) + if (one && two) { + if (!o->ignore_driver_algorithm && drv && drv->algorithm) + set_diff_algorithm(o, drv->algorithm); + builtin_diff(name, other ? other : name, one, two, xfrm_msg, must_show_header, o, complete_rewrite); - else + } else { fprintf(o->file, "* Unmerged path %s\n", name); + } } static void diff_fill_oid_info(struct diff_filespec *one, struct index_state *istate) @@ -4567,6 +4585,14 @@ static void run_diffstat(struct diff_filepair *p, struct diff_options *o, const char *name; const char *other; + if (!o->ignore_driver_algorithm) { + struct userdiff_driver *drv = userdiff_find_by_path(o->repo->index, + p->one->path); + + if (drv && drv->algorithm) + set_diff_algorithm(o, drv->algorithm); + } + if (DIFF_PAIR_UNMERGED(p)) { /* unmerged */ builtin_diffstat(p->one->path, NULL, NULL, NULL, @@ -5107,17 +5133,32 @@ static int diff_opt_diff_algorithm(const struct option *opt, const char *arg, int unset) { struct diff_options *options = opt->value; - long value = parse_algorithm_value(arg); BUG_ON_OPT_NEG(unset); - if (value < 0) + + if (set_diff_algorithm(options, arg)) 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; + options->ignore_driver_algorithm = 1; + + return 0; +} + +static int diff_opt_diff_algorithm_no_arg(const struct option *opt, + const char *arg, int unset) +{ + struct diff_options *options = opt->value; + + BUG_ON_OPT_NEG(unset); + BUG_ON_OPT_ARG(arg); + + if (set_diff_algorithm(options, opt->long_name)) + BUG("available diff algorithms include \"myers\", " + "\"minimal\", \"patience\" and \"histogram\""); + + options->ignore_driver_algorithm = 1; + return 0; } @@ -5250,7 +5291,6 @@ static int diff_opt_patience(const struct option *opt, BUG_ON_OPT_NEG(unset); BUG_ON_OPT_ARG(arg); - options->xdl_opts = DIFF_WITH_ALG(options, PATIENCE_DIFF); /* * Both --patience and --anchored use PATIENCE_DIFF * internally, so remove any anchors previously @@ -5259,7 +5299,9 @@ static int diff_opt_patience(const struct option *opt, for (i = 0; i < options->anchors_nr; i++) free(options->anchors[i]); options->anchors_nr = 0; - return 0; + options->ignore_driver_algorithm = 1; + + return set_diff_algorithm(options, "patience"); } static int diff_opt_ignore_regex(const struct option *opt, @@ -5562,9 +5604,10 @@ struct option *add_diff_options(const struct option *opts, N_("prevent rename/copy detection if the number of rename/copy targets exceeds given limit")), OPT_GROUP(N_("Diff algorithm options")), - OPT_BIT(0, "minimal", &options->xdl_opts, - N_("produce the smallest possible diff"), - XDF_NEED_MINIMAL), + OPT_CALLBACK_F(0, "minimal", options, NULL, + N_("produce the smallest possible diff"), + PARSE_OPT_NONEG | PARSE_OPT_NOARG, + diff_opt_diff_algorithm_no_arg), OPT_BIT_F('w', "ignore-all-space", &options->xdl_opts, N_("ignore whitespace when comparing lines"), XDF_IGNORE_WHITESPACE, PARSE_OPT_NONEG), @@ -5590,9 +5633,10 @@ struct option *add_diff_options(const struct option *opts, N_("generate diff using the \"patience diff\" algorithm"), PARSE_OPT_NONEG | PARSE_OPT_NOARG, diff_opt_patience), - OPT_BITOP(0, "histogram", &options->xdl_opts, - N_("generate diff using the \"histogram diff\" algorithm"), - XDF_HISTOGRAM_DIFF, XDF_DIFF_ALGORITHM_MASK), + OPT_CALLBACK_F(0, "histogram", options, NULL, + N_("generate diff using the \"histogram diff\" algorithm"), + PARSE_OPT_NONEG | PARSE_OPT_NOARG, + diff_opt_diff_algorithm_no_arg), OPT_CALLBACK_F(0, "diff-algorithm", options, N_("<algorithm>"), N_("choose a diff algorithm"), PARSE_OPT_NONEG, diff_opt_diff_algorithm), @@ -333,6 +333,7 @@ struct diff_options { int prefix_length; const char *stat_sep; int xdl_opts; + int ignore_driver_algorithm; /* see Documentation/diff-options.txt */ char **anchors; diff --git a/t/lib-diff-alternative.sh b/t/lib-diff-alternative.sh index 8d1e408bb5..a8f5d3274a 100644 --- a/t/lib-diff-alternative.sh +++ b/t/lib-diff-alternative.sh @@ -105,10 +105,46 @@ index $file1..$file2 100644 } EOF + cat >expect_diffstat <<EOF + file1 => file2 | 21 ++++++++++----------- + 1 file changed, 10 insertions(+), 11 deletions(-) +EOF + STRATEGY=$1 + test_expect_success "$STRATEGY diff from attributes" ' + echo "file* diff=driver" >.gitattributes && + git config diff.driver.algorithm "$STRATEGY" && + test_must_fail git diff --no-index file1 file2 > output && + cat expect && + cat output && + test_cmp expect output + ' + + test_expect_success "$STRATEGY diff from attributes has valid diffstat" ' + echo "file* diff=driver" >.gitattributes && + git config diff.driver.algorithm "$STRATEGY" && + test_must_fail git diff --stat --no-index file1 file2 > output && + test_cmp expect_diffstat output + ' + test_expect_success "$STRATEGY diff" ' - test_must_fail git diff --no-index "--$STRATEGY" file1 file2 > output && + test_must_fail git diff --no-index "--diff-algorithm=$STRATEGY" file1 file2 > output && + test_cmp expect output + ' + + test_expect_success "$STRATEGY diff command line precedence before attributes" ' + echo "file* diff=driver" >.gitattributes && + git config diff.driver.algorithm myers && + test_must_fail git diff --no-index "--diff-algorithm=$STRATEGY" file1 file2 > output && + test_cmp expect output + ' + + test_expect_success "$STRATEGY diff attributes precedence before config" ' + git config diff.algorithm default && + echo "file* diff=driver" >.gitattributes && + git config diff.driver.algorithm "$STRATEGY" && + test_must_fail git diff --no-index file1 file2 > output && test_cmp expect output ' diff --git a/userdiff.c b/userdiff.c index 94cca1a2a8..58a3d59ef8 100644 --- a/userdiff.c +++ b/userdiff.c @@ -293,7 +293,7 @@ PATTERNS("scheme", "|([^][)(}{[ \t])+"), PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$", "\\\\[a-zA-Z@]+|\\\\.|[a-zA-Z0-9\x80-\xff]+"), -{ "default", NULL, -1, { NULL, 0 } }, +{ "default", NULL, NULL, -1, { NULL, 0 } }, }; #undef PATTERNS #undef IPATTERN @@ -394,6 +394,8 @@ int userdiff_config(const char *k, const char *v) return parse_bool(&drv->textconv_want_cache, k, v); if (!strcmp(type, "wordregex")) return git_config_string(&drv->word_regex, k, v); + if (!strcmp(type, "algorithm")) + return git_config_string(&drv->algorithm, k, v); return 0; } diff --git a/userdiff.h b/userdiff.h index aee91bc77e..24419db697 100644 --- a/userdiff.h +++ b/userdiff.h @@ -14,6 +14,7 @@ struct userdiff_funcname { struct userdiff_driver { const char *name; const char *external; + const char *algorithm; int binary; struct userdiff_funcname funcname; const char *word_regex; |