Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Browse files

diffcore-rename: fall back to -C when -C -C busts the rename limit

When there are too many paths in the project, the number of rename source
candidates "git diff -C -C" finds will exceed the rename detection limit,
and no inexact rename detection is performed.  We however could fall back
to "git diff -C" if the number of modified paths is sufficiently small.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
  • Loading branch information...
commit f31027c99cb2ec4eb7ad8d1ebc7f0e20fef4bd1d 1 parent e88d6bc
@gitster gitster authored
View
12 builtin/diff-tree.c
@@ -163,6 +163,9 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
}
if (read_stdin) {
+ int saved_nrl = 0;
+ int saved_dcctc = 0;
+
if (opt->diffopt.detect_rename)
opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
DIFF_SETUP_USE_CACHE);
@@ -173,9 +176,16 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
fputs(line, stdout);
fflush(stdout);
}
- else
+ else {
diff_tree_stdin(line);
+ if (saved_nrl < opt->diffopt.needed_rename_limit)
+ saved_nrl = opt->diffopt.needed_rename_limit;
+ if (opt->diffopt.degraded_cc_to_c)
+ saved_dcctc = 1;
+ }
}
+ opt->diffopt.degraded_cc_to_c = saved_dcctc;
+ opt->diffopt.needed_rename_limit = saved_nrl;
}
return diff_result_code(&opt->diffopt, 0);
View
9 builtin/log.c
@@ -247,6 +247,8 @@ static void finish_early_output(struct rev_info *rev)
static int cmd_log_walk(struct rev_info *rev)
{
struct commit *commit;
+ int saved_nrl = 0;
+ int saved_dcctc = 0;
if (rev->early_output)
setup_early_output(rev);
@@ -277,7 +279,14 @@ static int cmd_log_walk(struct rev_info *rev)
}
free_commit_list(commit->parents);
commit->parents = NULL;
+ if (saved_nrl < rev->diffopt.needed_rename_limit)
+ saved_nrl = rev->diffopt.needed_rename_limit;
+ if (rev->diffopt.degraded_cc_to_c)
+ saved_dcctc = 1;
}
+ rev->diffopt.degraded_cc_to_c = saved_dcctc;
+ rev->diffopt.needed_rename_limit = saved_nrl;
+
if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
return 02;
View
26 diff.c
@@ -3956,6 +3956,28 @@ static int is_summary_empty(const struct diff_queue_struct *q)
return 1;
}
+static const char rename_limit_warning[] =
+"inexact rename detection was skipped due to too many files.";
+
+static const char degrade_cc_to_c_warning[] =
+"only found copies from modified paths due to too many files.";
+
+static const char rename_limit_advice[] =
+"you may want to set your %s variable to at least "
+"%d and retry the command.";
+
+void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
+{
+ if (degraded_cc)
+ warning(degrade_cc_to_c_warning);
+ else if (needed)
+ warning(rename_limit_warning);
+ else
+ return;
+ if (0 < needed && needed < 32767)
+ warning(rename_limit_advice, varname, needed);
+}
+
void diff_flush(struct diff_options *options)
{
struct diff_queue_struct *q = &diff_queued_diff;
@@ -4237,6 +4259,10 @@ void diffcore_std(struct diff_options *options)
int diff_result_code(struct diff_options *opt, int status)
{
int result = 0;
+
+ diff_warn_rename_limit("diff.renamelimit",
+ opt->needed_rename_limit,
+ opt->degraded_cc_to_c);
if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
!(opt->output_format & DIFF_FORMAT_CHECKDIFF))
return status;
View
2  diff.h
@@ -111,6 +111,7 @@ struct diff_options {
int rename_score;
int rename_limit;
int needed_rename_limit;
+ int degraded_cc_to_c;
int show_rename_progress;
int dirstat_percent;
int setup;
@@ -273,6 +274,7 @@ extern void diffcore_fix_diff_index(struct diff_options *);
extern int diff_queue_is_empty(void);
extern void diff_flush(struct diff_options*);
+extern void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc);
/* diff-raw status letters */
#define DIFF_STATUS_ADDED 'A'
View
38 diffcore-rename.c
@@ -420,11 +420,18 @@ static void record_if_better(struct diff_score m[], struct diff_score *o)
m[worst] = *o;
}
+/*
+ * Returns:
+ * 0 if we are under the limit;
+ * 1 if we need to disable inexact rename detection;
+ * 2 if we would be under the limit if we were given -C instead of -C -C.
+ */
static int too_many_rename_candidates(int num_create,
struct diff_options *options)
{
int rename_limit = options->rename_limit;
int num_src = rename_src_nr;
+ int i;
options->needed_rename_limit = 0;
@@ -445,6 +452,20 @@ static int too_many_rename_candidates(int num_create,
options->needed_rename_limit =
num_src > num_create ? num_src : num_create;
+
+ /* Are we running under -C -C? */
+ if (!DIFF_OPT_TST(options, FIND_COPIES_HARDER))
+ return 1;
+
+ /* Would we bust the limit if we were running under -C? */
+ for (num_src = i = 0; i < rename_src_nr; i++) {
+ if (diff_unmodified_pair(rename_src[i].p))
+ continue;
+ num_src++;
+ }
+ if ((num_create <= rename_limit || num_src <= rename_limit) &&
+ (num_create * num_src <= rename_limit * rename_limit))
+ return 2;
return 1;
}
@@ -476,7 +497,7 @@ void diffcore_rename(struct diff_options *options)
struct diff_queue_struct *q = &diff_queued_diff;
struct diff_queue_struct outq;
struct diff_score *mx;
- int i, j, rename_count;
+ int i, j, rename_count, skip_unmodified = 0;
int num_create, num_src, dst_cnt;
struct progress *progress = NULL;
@@ -539,8 +560,16 @@ void diffcore_rename(struct diff_options *options)
if (!num_create)
goto cleanup;
- if (too_many_rename_candidates(num_create, options))
+ switch (too_many_rename_candidates(num_create, options)) {
+ case 1:
goto cleanup;
+ case 2:
+ options->degraded_cc_to_c = 1;
+ skip_unmodified = 1;
+ break;
+ default:
+ break;
+ }
if (options->show_rename_progress) {
progress = start_progress_delay(
@@ -563,6 +592,11 @@ void diffcore_rename(struct diff_options *options)
for (j = 0; j < rename_src_nr; j++) {
struct diff_filespec *one = rename_src[j].p->one;
struct diff_score this_src;
+
+ if (skip_unmodified &&
+ diff_unmodified_pair(rename_src[j].p))
+ continue;
+
this_src.score = estimate_similarity(one, two,
minimum_score);
this_src.name_score = basename_same(one, two);
View
10 merge-recursive.c
@@ -22,11 +22,6 @@
#include "dir.h"
#include "submodule.h"
-static const char rename_limit_advice[] =
-"inexact rename detection was skipped because there were too many\n"
-" files. You may want to set your merge.renamelimit variable to at least\n"
-" %d and retry this merge.";
-
static struct tree *shift_tree_object(struct tree *one, struct tree *two,
const char *subtree_shift)
{
@@ -1656,8 +1651,9 @@ int merge_recursive(struct merge_options *o,
commit_list_insert(h2, &(*result)->parents->next);
}
flush_output(o);
- if (o->needed_rename_limit)
- warning(rename_limit_advice, o->needed_rename_limit);
+ if (show(o, 2))
+ diff_warn_rename_limit("merge.renamelimit",
+ o->needed_rename_limit, 0);
return clean;
}
View
25 t/t4001-diff-rename.sh
@@ -77,4 +77,29 @@ test_expect_success 'favour same basenames even with minor differences' '
git show HEAD:path1 | sed "s/15/16/" > subdir/path1 &&
git status | grep "renamed: .*path1 -> subdir/path1"'
+test_expect_success 'setup for many rename source candidates' '
+ git reset --hard &&
+ for i in 0 1 2 3 4 5 6 7 8 9;
+ do
+ for j in 0 1 2 3 4 5 6 7 8 9;
+ do
+ echo "$i$j" >"path$i$j"
+ done
+ done &&
+ git add "path??" &&
+ test_tick &&
+ git commit -m "hundred" &&
+ (cat path1; echo new) >new-path &&
+ echo old >>path1 &&
+ git add new-path path1 &&
+ git diff -l 4 -C -C --cached --name-status >actual 2>actual.err &&
+ sed -e "s/^\([CM]\)[0-9]* /\1 /" actual >actual.munged &&
+ cat >expect <<-EOF &&
+ C path1 new-path
+ M path1
+ EOF
+ test_cmp expect actual.munged &&
+ grep warning actual.err
+'
+
test_done
Please sign in to comment.
Something went wrong with that request. Please try again.