Merge branch 'jk/diff-follow-must-take-one-pathspec'
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index a99b925ac74bc4f513bd9d860e757f385cca871b..de25819e4edede0a24ee30b202dee478165b4fed 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -16,6 +16,7 @@
 #include "submodule.h"
 #include "ll-merge.h"
 #include "string-list.h"
+#include "argv-array.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
 #define FAST_WORKING_DIRECTORY 0
@@ -30,6 +31,7 @@ static int diff_use_color_default = -1;
 static int diff_context_default = 3;
 static const char *diff_word_regex_cfg;
 static const char *external_diff_cmd_cfg;
+static const char *diff_order_file_cfg;
 int diff_auto_refresh_index = 1;
 static int diff_mnemonic_prefix;
 static int diff_no_prefix;
@@ -201,6 +203,8 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
                return git_config_string(&external_diff_cmd_cfg, var, value);
        if (!strcmp(var, "diff.wordregex"))
                return git_config_string(&diff_word_regex_cfg, var, value);
+       if (!strcmp(var, "diff.orderfile"))
+               return git_config_pathname(&diff_order_file_cfg, var, value);
 
        if (!strcmp(var, "diff.ignoresubmodules"))
                handle_ignore_submodules_arg(&default_diff_options, value);
@@ -235,7 +239,7 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
        if (userdiff_config(var, value) < 0)
                return -1;
 
-       if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
+       if (starts_with(var, "diff.color.") || starts_with(var, "color.diff.")) {
                int slot = parse_diff_color_slot(var, 11);
                if (slot < 0)
                        return 0;
@@ -264,7 +268,7 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
                return 0;
        }
 
-       if (!prefixcmp(var, "submodule."))
+       if (starts_with(var, "submodule."))
                return parse_submodule_config_option(var, value);
 
        return git_default_config(var, value, cb);
@@ -1215,7 +1219,7 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                        diff_words_append(line, len,
                                          &ecbdata->diff_words->plus);
                        return;
-               } else if (!prefixcmp(line, "\\ ")) {
+               } else if (starts_with(line, "\\ ")) {
                        /*
                         * Eat the "no newline at eof" marker as if we
                         * saw a "+" or "-" line with nothing on it,
@@ -1358,11 +1362,7 @@ static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 {
        struct diffstat_file *x;
        x = xcalloc(sizeof (*x), 1);
-       if (diffstat->nr == diffstat->alloc) {
-               diffstat->alloc = alloc_nr(diffstat->alloc);
-               diffstat->files = xrealloc(diffstat->files,
-                               diffstat->alloc * sizeof(x));
-       }
+       ALLOC_GROW(diffstat->files, diffstat->nr + 1, diffstat->alloc);
        diffstat->files[diffstat->nr++] = x;
        if (name_b) {
                x->from_name = xstrdup(name_a);
@@ -1462,20 +1462,12 @@ int print_stat_summary(FILE *fp, int files, int insertions, int deletions)
         * but nothing about added/removed lines? Is this a bug in Git?").
         */
        if (insertions || deletions == 0) {
-               /*
-                * TRANSLATORS: "+" in (+) is a line addition marker;
-                * do not translate it.
-                */
                strbuf_addf(&sb,
                            (insertions == 1) ? ", %d insertion(+)" : ", %d insertions(+)",
                            insertions);
        }
 
        if (deletions || insertions == 0) {
-               /*
-                * TRANSLATORS: "-" in (-) is a line removal marker;
-                * do not translate it.
-                */
                strbuf_addf(&sb,
                            (deletions == 1) ? ", %d deletion(-)" : ", %d deletions(-)",
                            deletions);
@@ -2387,9 +2379,9 @@ static void builtin_diff(const char *name_a,
                        xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
                if (!diffopts)
                        ;
-               else if (!prefixcmp(diffopts, "--unified="))
+               else if (starts_with(diffopts, "--unified="))
                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
-               else if (!prefixcmp(diffopts, "-u"))
+               else if (starts_with(diffopts, "-u"))
                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
                if (o->word_diff)
                        init_diff_words_data(&ecbdata, o, one, two);
@@ -2842,8 +2834,9 @@ static struct diff_tempfile *prepare_temp_file(const char *name,
                remove_tempfile_installed = 1;
        }
 
-       if (!one->sha1_valid ||
-           reuse_worktree_file(name, one->sha1, 1)) {
+       if (!S_ISGITLINK(one->mode) &&
+           (!one->sha1_valid ||
+            reuse_worktree_file(name, one->sha1, 1))) {
                struct stat st;
                if (lstat(name, &st) < 0) {
                        if (errno == ENOENT)
@@ -2887,6 +2880,16 @@ static struct diff_tempfile *prepare_temp_file(const char *name,
        return temp;
 }
 
+static void add_external_diff_name(struct argv_array *argv,
+                                  const char *name,
+                                  struct diff_filespec *df)
+{
+       struct diff_tempfile *temp = prepare_temp_file(name, df);
+       argv_array_push(argv, temp->name);
+       argv_array_push(argv, temp->hex);
+       argv_array_push(argv, temp->mode);
+}
+
 /* An external diff command takes:
  *
  * diff-cmd name infile1 infile1-sha1 infile1-mode \
@@ -2899,41 +2902,36 @@ static void run_external_diff(const char *pgm,
                              struct diff_filespec *one,
                              struct diff_filespec *two,
                              const char *xfrm_msg,
-                             int complete_rewrite)
+                             int complete_rewrite,
+                             struct diff_options *o)
 {
-       const char *spawn_arg[10];
-       int retval;
-       const char **arg = &spawn_arg[0];
+       struct argv_array argv = ARGV_ARRAY_INIT;
+       struct argv_array env = ARGV_ARRAY_INIT;
+       struct diff_queue_struct *q = &diff_queued_diff;
+
+       argv_array_push(&argv, pgm);
+       argv_array_push(&argv, name);
 
        if (one && two) {
-               struct diff_tempfile *temp_one, *temp_two;
-               const char *othername = (other ? other : name);
-               temp_one = prepare_temp_file(name, one);
-               temp_two = prepare_temp_file(othername, two);
-               *arg++ = pgm;
-               *arg++ = name;
-               *arg++ = temp_one->name;
-               *arg++ = temp_one->hex;
-               *arg++ = temp_one->mode;
-               *arg++ = temp_two->name;
-               *arg++ = temp_two->hex;
-               *arg++ = temp_two->mode;
-               if (other) {
-                       *arg++ = other;
-                       *arg++ = xfrm_msg;
+               add_external_diff_name(&argv, name, one);
+               if (!other)
+                       add_external_diff_name(&argv, name, two);
+               else {
+                       add_external_diff_name(&argv, other, two);
+                       argv_array_push(&argv, other);
+                       argv_array_push(&argv, xfrm_msg);
                }
-       } else {
-               *arg++ = pgm;
-               *arg++ = name;
        }
-       *arg = NULL;
-       fflush(NULL);
-       retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
+
+       argv_array_pushf(&env, "GIT_DIFF_PATH_COUNTER=%d", ++o->diff_path_counter);
+       argv_array_pushf(&env, "GIT_DIFF_PATH_TOTAL=%d", q->nr);
+
+       if (run_command_v_opt_cd_env(argv.argv, RUN_USING_SHELL, NULL, env.argv))
+               die(_("external diff died, stopping at %s"), name);
+
        remove_tempfile();
-       if (retval) {
-               fprintf(stderr, "external diff died, stopping at %s.\n", name);
-               exit(1);
-       }
+       argv_array_clear(&argv);
+       argv_array_clear(&env);
 }
 
 static int similarity_index(struct diff_filepair *p)
@@ -3042,7 +3040,7 @@ static void run_diff_cmd(const char *pgm,
 
        if (pgm) {
                run_external_diff(pgm, name, other, one, two, xfrm_msg,
-                                 complete_rewrite);
+                                 complete_rewrite, o);
                return;
        }
        if (one && two)
@@ -3201,12 +3199,15 @@ void diff_setup(struct diff_options *options)
        options->context = diff_context_default;
        DIFF_OPT_SET(options, RENAME_EMPTY);
 
+       /* pathchange left =NULL by default */
        options->change = diff_change;
        options->add_remove = diff_addremove;
        options->use_color = diff_use_color_default;
        options->detect_rename = diff_detect_rename_default;
        options->xdl_opts |= diff_algorithm;
 
+       options->orderfile = diff_order_file_cfg;
+
        if (diff_no_prefix) {
                options->a_prefix = options->b_prefix = "";
        } else if (!diff_mnemonic_prefix) {
@@ -3318,6 +3319,8 @@ void diff_setup_done(struct diff_options *options)
                DIFF_OPT_SET(options, EXIT_WITH_STATUS);
        }
 
+       options->diff_path_counter = 0;
+
        if (DIFF_OPT_TST(options, FOLLOW_RENAMES) && options->pathspec.nr != 1)
                die(_("--follow requires exactly one pathspec"));
 }
@@ -3349,14 +3352,11 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
        if (c != '-')
                return 0;
        arg++;
-       eq = strchr(arg, '=');
-       if (eq)
-               len = eq - arg;
-       else
-               len = strlen(arg);
+       eq = strchrnul(arg, '=');
+       len = eq - arg;
        if (!len || strncmp(arg, arg_long, len))
                return 0;
-       if (eq) {
+       if (*eq) {
                int n;
                char *end;
                if (!isdigit(*++eq))
@@ -3394,10 +3394,10 @@ int parse_long_opt(const char *opt, const char **argv,
        if (arg[0] != '-' || arg[1] != '-')
                return 0;
        arg += strlen("--");
-       if (prefixcmp(arg, opt))
+       if (!starts_with(arg, opt))
                return 0;
        arg += strlen(opt);
-       if (*arg == '=') { /* sticked form: --option=value */
+       if (*arg == '=') { /* stuck form: --option=value */
                *optarg = arg + 1;
                return 1;
        }
@@ -3425,7 +3425,7 @@ static int stat_opt(struct diff_options *options, const char **av)
 
        switch (*arg) {
        case '-':
-               if (!prefixcmp(arg, "-width")) {
+               if (starts_with(arg, "-width")) {
                        arg += strlen("-width");
                        if (*arg == '=')
                                width = strtoul(arg + 1, &end, 10);
@@ -3435,7 +3435,7 @@ static int stat_opt(struct diff_options *options, const char **av)
                                width = strtoul(av[1], &end, 10);
                                argcount = 2;
                        }
-               } else if (!prefixcmp(arg, "-name-width")) {
+               } else if (starts_with(arg, "-name-width")) {
                        arg += strlen("-name-width");
                        if (*arg == '=')
                                name_width = strtoul(arg + 1, &end, 10);
@@ -3445,7 +3445,7 @@ static int stat_opt(struct diff_options *options, const char **av)
                                name_width = strtoul(av[1], &end, 10);
                                argcount = 2;
                        }
-               } else if (!prefixcmp(arg, "-graph-width")) {
+               } else if (starts_with(arg, "-graph-width")) {
                        arg += strlen("-graph-width");
                        if (*arg == '=')
                                graph_width = strtoul(arg + 1, &end, 10);
@@ -3455,7 +3455,7 @@ static int stat_opt(struct diff_options *options, const char **av)
                                graph_width = strtoul(av[1], &end, 10);
                                argcount = 2;
                        }
-               } else if (!prefixcmp(arg, "-count")) {
+               } else if (starts_with(arg, "-count")) {
                        arg += strlen("-count");
                        if (*arg == '=')
                                count = strtoul(arg + 1, &end, 10);
@@ -3583,14 +3583,6 @@ static int parse_diff_filter_opt(const char *optarg, struct diff_options *opt)
        return 0;
 }
 
-/* Used only by "diff-files" and "diff --no-index" */
-void handle_deprecated_show_diff_q(struct diff_options *opt)
-{
-       warning("'diff -q' and 'diff-files -q' are deprecated.");
-       warning("Use 'diff --diff-filter=d' instead to ignore deleted filepairs.");
-       parse_diff_filter_opt("d", opt);
-}
-
 static void enable_patch_output(int *fmt) {
        *fmt &= ~DIFF_FORMAT_NO_OUTPUT;
        *fmt |= DIFF_FORMAT_PATCH;
@@ -3617,15 +3609,15 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->output_format |= DIFF_FORMAT_SHORTSTAT;
        else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
                return parse_dirstat_opt(options, "");
-       else if (!prefixcmp(arg, "-X"))
+       else if (starts_with(arg, "-X"))
                return parse_dirstat_opt(options, arg + 2);
-       else if (!prefixcmp(arg, "--dirstat="))
+       else if (starts_with(arg, "--dirstat="))
                return parse_dirstat_opt(options, arg + 10);
        else if (!strcmp(arg, "--cumulative"))
                return parse_dirstat_opt(options, "cumulative");
        else if (!strcmp(arg, "--dirstat-by-file"))
                return parse_dirstat_opt(options, "files");
-       else if (!prefixcmp(arg, "--dirstat-by-file=")) {
+       else if (starts_with(arg, "--dirstat-by-file=")) {
                parse_dirstat_opt(options, "files");
                return parse_dirstat_opt(options, arg + 18);
        }
@@ -3642,17 +3634,17 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->output_format |= DIFF_FORMAT_NAME_STATUS;
        else if (!strcmp(arg, "-s") || !strcmp(arg, "--no-patch"))
                options->output_format |= DIFF_FORMAT_NO_OUTPUT;
-       else if (!prefixcmp(arg, "--stat"))
+       else if (starts_with(arg, "--stat"))
                /* --stat, --stat-width, --stat-name-width, or --stat-count */
                return stat_opt(options, av);
 
        /* renames options */
-       else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
+       else if (starts_with(arg, "-B") || starts_with(arg, "--break-rewrites=") ||
                 !strcmp(arg, "--break-rewrites")) {
                if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
                        return error("invalid argument to -B: %s", arg+2);
        }
-       else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
+       else if (starts_with(arg, "-M") || starts_with(arg, "--find-renames=") ||
                 !strcmp(arg, "--find-renames")) {
                if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
                        return error("invalid argument to -M: %s", arg+2);
@@ -3661,7 +3653,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
                options->irreversible_delete = 1;
        }
-       else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
+       else if (starts_with(arg, "-C") || starts_with(arg, "--find-copies=") ||
                 !strcmp(arg, "--find-copies")) {
                if (options->detect_rename == DIFF_DETECT_COPY)
                        DIFF_OPT_SET(options, FIND_COPIES_HARDER);
@@ -3677,7 +3669,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                DIFF_OPT_CLR(options, RENAME_EMPTY);
        else if (!strcmp(arg, "--relative"))
                DIFF_OPT_SET(options, RELATIVE_NAME);
-       else if (!prefixcmp(arg, "--relative=")) {
+       else if (starts_with(arg, "--relative=")) {
                DIFF_OPT_SET(options, RELATIVE_NAME);
                options->prefix = arg + 11;
        }
@@ -3730,7 +3722,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                DIFF_OPT_CLR(options, FOLLOW_RENAMES);
        else if (!strcmp(arg, "--color"))
                options->use_color = 1;
-       else if (!prefixcmp(arg, "--color=")) {
+       else if (starts_with(arg, "--color=")) {
                int value = git_config_colorbool(NULL, arg+8);
                if (value < 0)
                        return error("option `color' expects \"always\", \"auto\", or \"never\"");
@@ -3742,7 +3734,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->use_color = 1;
                options->word_diff = DIFF_WORDS_COLOR;
        }
-       else if (!prefixcmp(arg, "--color-words=")) {
+       else if (starts_with(arg, "--color-words=")) {
                options->use_color = 1;
                options->word_diff = DIFF_WORDS_COLOR;
                options->word_regex = arg + 14;
@@ -3751,7 +3743,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                if (options->word_diff == DIFF_WORDS_NONE)
                        options->word_diff = DIFF_WORDS_PLAIN;
        }
-       else if (!prefixcmp(arg, "--word-diff=")) {
+       else if (starts_with(arg, "--word-diff=")) {
                const char *type = arg + 12;
                if (!strcmp(type, "plain"))
                        options->word_diff = DIFF_WORDS_PLAIN;
@@ -3787,12 +3779,12 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        else if (!strcmp(arg, "--ignore-submodules")) {
                DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
                handle_ignore_submodules_arg(options, "all");
-       } else if (!prefixcmp(arg, "--ignore-submodules=")) {
+       } else if (starts_with(arg, "--ignore-submodules=")) {
                DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
                handle_ignore_submodules_arg(options, arg + 20);
        } else if (!strcmp(arg, "--submodule"))
                DIFF_OPT_SET(options, SUBMODULE_LOG);
-       else if (!prefixcmp(arg, "--submodule="))
+       else if (starts_with(arg, "--submodule="))
                return parse_submodule_opt(options, arg + 12);
 
        /* misc options */
@@ -3828,7 +3820,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        }
        else if (!strcmp(arg, "--abbrev"))
                options->abbrev = DEFAULT_ABBREV;
-       else if (!prefixcmp(arg, "--abbrev=")) {
+       else if (starts_with(arg, "--abbrev=")) {
                options->abbrev = strtoul(arg + 9, NULL, 10);
                if (options->abbrev < MINIMUM_ABBREV)
                        options->abbrev = MINIMUM_ABBREV;
@@ -3910,22 +3902,22 @@ static int diff_scoreopt_parse(const char *opt)
        cmd = *opt++;
        if (cmd == '-') {
                /* convert the long-form arguments into short-form versions */
-               if (!prefixcmp(opt, "break-rewrites")) {
+               if (starts_with(opt, "break-rewrites")) {
                        opt += strlen("break-rewrites");
                        if (*opt == 0 || *opt++ == '=')
                                cmd = 'B';
-               } else if (!prefixcmp(opt, "find-copies")) {
+               } else if (starts_with(opt, "find-copies")) {
                        opt += strlen("find-copies");
                        if (*opt == 0 || *opt++ == '=')
                                cmd = 'C';
-               } else if (!prefixcmp(opt, "find-renames")) {
+               } else if (starts_with(opt, "find-renames")) {
                        opt += strlen("find-renames");
                        if (*opt == 0 || *opt++ == '=')
                                cmd = 'M';
                }
        }
        if (cmd != 'M' && cmd != 'C' && cmd != 'B')
-               return -1; /* that is not a -M, -C nor -B option */
+               return -1; /* that is not a -M, -Cor -B option */
 
        opt1 = parse_rename_score(&opt);
        if (cmd != 'B')
@@ -3949,11 +3941,7 @@ struct diff_queue_struct diff_queued_diff;
 
 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
 {
-       if (queue->alloc <= queue->nr) {
-               queue->alloc = alloc_nr(queue->alloc);
-               queue->queue = xrealloc(queue->queue,
-                                       sizeof(dp) * queue->alloc);
-       }
+       ALLOC_GROW(queue->queue, queue->nr + 1, queue->alloc);
        queue->queue[queue->nr++] = dp;
 }
 
@@ -4123,9 +4111,9 @@ void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
                DIFF_FILE_VALID(s) ? "valid" : "invalid",
                s->mode,
                s->sha1_valid ? sha1_to_hex(s->sha1) : "");
-       fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
+       fprintf(stderr, "queue[%d] %s size %lu\n",
                x, one ? one : "",
-               s->size, s->xfrm_flags);
+               s->size);
 }
 
 void diff_debug_filepair(const struct diff_filepair *p, int i)
@@ -4328,7 +4316,7 @@ static void patch_id_consume(void *priv, char *line, unsigned long len)
        int new_len;
 
        /* Ignore line numbers when computing the SHA1 of the patch */
-       if (!prefixcmp(line, "@@ -"))
+       if (starts_with(line, "@@ -"))
                return;
 
        new_len = remove_space(line, len);
@@ -4681,6 +4669,38 @@ static int diff_filespec_is_identical(struct diff_filespec *one,
        return !memcmp(one->data, two->data, one->size);
 }
 
+static int diff_filespec_check_stat_unmatch(struct diff_filepair *p)
+{
+       if (p->done_skip_stat_unmatch)
+               return p->skip_stat_unmatch_result;
+
+       p->done_skip_stat_unmatch = 1;
+       p->skip_stat_unmatch_result = 0;
+       /*
+        * 1. Entries that come from stat info dirtiness
+        *    always have both sides (iow, not create/delete),
+        *    one side of the object name is unknown, with
+        *    the same mode and size.  Keep the ones that
+        *    do not match these criteria.  They have real
+        *    differences.
+        *
+        * 2. At this point, the file is known to be modified,
+        *    with the same mode and size, and the object
+        *    name of one side is unknown.  Need to inspect
+        *    the identical contents.
+        */
+       if (!DIFF_FILE_VALID(p->one) || /* (1) */
+           !DIFF_FILE_VALID(p->two) ||
+           (p->one->sha1_valid && p->two->sha1_valid) ||
+           (p->one->mode != p->two->mode) ||
+           diff_populate_filespec(p->one, 1) ||
+           diff_populate_filespec(p->two, 1) ||
+           (p->one->size != p->two->size) ||
+           !diff_filespec_is_identical(p->one, p->two)) /* (2) */
+               p->skip_stat_unmatch_result = 1;
+       return p->skip_stat_unmatch_result;
+}
+
 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
 {
        int i;
@@ -4691,27 +4711,7 @@ static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
 
-               /*
-                * 1. Entries that come from stat info dirtiness
-                *    always have both sides (iow, not create/delete),
-                *    one side of the object name is unknown, with
-                *    the same mode and size.  Keep the ones that
-                *    do not match these criteria.  They have real
-                *    differences.
-                *
-                * 2. At this point, the file is known to be modified,
-                *    with the same mode and size, and the object
-                *    name of one side is unknown.  Need to inspect
-                *    the identical contents.
-                */
-               if (!DIFF_FILE_VALID(p->one) || /* (1) */
-                   !DIFF_FILE_VALID(p->two) ||
-                   (p->one->sha1_valid && p->two->sha1_valid) ||
-                   (p->one->mode != p->two->mode) ||
-                   diff_populate_filespec(p->one, 1) ||
-                   diff_populate_filespec(p->two, 1) ||
-                   (p->one->size != p->two->size) ||
-                   !diff_filespec_is_identical(p->one, p->two)) /* (2) */
+               if (diff_filespec_check_stat_unmatch(p))
                        diff_q(&outq, p);
                else {
                        /*
@@ -4747,6 +4747,7 @@ void diffcore_fix_diff_index(struct diff_options *options)
 
 void diffcore_std(struct diff_options *options)
 {
+       /* NOTE please keep the following in sync with diff_tree_combined() */
        if (options->skip_stat_unmatch)
                diffcore_skip_stat_unmatch(options);
        if (!options->found_follow) {
@@ -4874,6 +4875,7 @@ void diff_change(struct diff_options *options,
                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
 {
        struct diff_filespec *one, *two;
+       struct diff_filepair *p;
 
        if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
            is_submodule_ignored(concatpath, options))
@@ -4900,10 +4902,16 @@ void diff_change(struct diff_options *options,
        fill_filespec(two, new_sha1, new_sha1_valid, new_mode);
        one->dirty_submodule = old_dirty_submodule;
        two->dirty_submodule = new_dirty_submodule;
+       p = diff_queue(&diff_queued_diff, one, two);
 
-       diff_queue(&diff_queued_diff, one, two);
-       if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
-               DIFF_OPT_SET(options, HAS_CHANGES);
+       if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
+               return;
+
+       if (DIFF_OPT_TST(options, QUICK) && options->skip_stat_unmatch &&
+           !diff_filespec_check_stat_unmatch(p))
+               return;
+
+       DIFF_OPT_SET(options, HAS_CHANGES);
 }
 
 struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)