Move computation of dir_rename_count from merge-ort to diffcore-rename
Move the computation of dir_rename_count from merge-ort.c to
diffcore-rename.c, making slight adjustments to the data structures
based on the move. While the diffstat looks large, viewing this commit
with --color-moved makes it clear that only about 20 lines changed.
With this patch, the computation of dir_rename_count is still only done
after inexact rename detection, but subsequent commits will add a
preliminary computation of dir_rename_count after exact rename
detection, followed by some updates after inexact rename detection.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/diffcore-rename.c b/diffcore-rename.c
index 8eeb8c7..39e23d5 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -380,6 +380,129 @@ static char *get_dirname(const char *filename)
return slash ? xstrndup(filename, slash - filename) : xstrdup("");
}
+static void dirname_munge(char *filename)
+{
+ char *slash = strrchr(filename, '/');
+ if (!slash)
+ slash = filename;
+ *slash = '\0';
+}
+
+static void increment_count(struct strmap *dir_rename_count,
+ char *old_dir,
+ char *new_dir)
+{
+ struct strintmap *counts;
+ struct strmap_entry *e;
+
+ /* Get the {new_dirs -> counts} mapping using old_dir */
+ e = strmap_get_entry(dir_rename_count, old_dir);
+ if (e) {
+ counts = e->value;
+ } else {
+ counts = xmalloc(sizeof(*counts));
+ strintmap_init_with_options(counts, 0, NULL, 1);
+ strmap_put(dir_rename_count, old_dir, counts);
+ }
+
+ /* Increment the count for new_dir */
+ strintmap_incr(counts, new_dir, 1);
+}
+
+static void update_dir_rename_counts(struct strmap *dir_rename_count,
+ struct strset *dirs_removed,
+ const char *oldname,
+ const char *newname)
+{
+ char *old_dir = xstrdup(oldname);
+ char *new_dir = xstrdup(newname);
+ char new_dir_first_char = new_dir[0];
+ int first_time_in_loop = 1;
+
+ while (1) {
+ dirname_munge(old_dir);
+ dirname_munge(new_dir);
+
+ /*
+ * When renaming
+ * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
+ * then this suggests that both
+ * a/b/c/d/e/ => a/b/some/thing/else/e/
+ * a/b/c/d/ => a/b/some/thing/else/
+ * so we want to increment counters for both. We do NOT,
+ * however, also want to suggest that there was the following
+ * rename:
+ * a/b/c/ => a/b/some/thing/
+ * so we need to quit at that point.
+ *
+ * Note the when first_time_in_loop, we only strip off the
+ * basename, and we don't care if that's different.
+ */
+ if (!first_time_in_loop) {
+ char *old_sub_dir = strchr(old_dir, '\0')+1;
+ char *new_sub_dir = strchr(new_dir, '\0')+1;
+ if (!*new_dir) {
+ /*
+ * Special case when renaming to root directory,
+ * i.e. when new_dir == "". In this case, we had
+ * something like
+ * a/b/subdir => subdir
+ * and so dirname_munge() sets things up so that
+ * old_dir = "a/b\0subdir\0"
+ * new_dir = "\0ubdir\0"
+ * We didn't have a '/' to overwrite a '\0' onto
+ * in new_dir, so we have to compare differently.
+ */
+ if (new_dir_first_char != old_sub_dir[0] ||
+ strcmp(old_sub_dir+1, new_sub_dir))
+ break;
+ } else {
+ if (strcmp(old_sub_dir, new_sub_dir))
+ break;
+ }
+ }
+
+ if (strset_contains(dirs_removed, old_dir))
+ increment_count(dir_rename_count, old_dir, new_dir);
+ else
+ break;
+
+ /* If we hit toplevel directory ("") for old or new dir, quit */
+ if (!*old_dir || !*new_dir)
+ break;
+
+ first_time_in_loop = 0;
+ }
+
+ /* Free resources we don't need anymore */
+ free(old_dir);
+ free(new_dir);
+}
+
+static void compute_dir_rename_counts(struct strmap *dir_rename_count,
+ struct strset *dirs_removed)
+{
+ int i;
+
+ /* Set up dir_rename_count */
+ for (i = 0; i < rename_dst_nr; ++i) {
+ /* File not part of directory rename counts if not a rename */
+ if (!rename_dst[i].is_rename)
+ continue;
+
+ /*
+ * Make dir_rename_count contain a map of a map:
+ * old_directory -> {new_directory -> count}
+ * In other words, for every pair look at the directories for
+ * the old filename and the new filename and count how many
+ * times that pairing occurs.
+ */
+ update_dir_rename_counts(dir_rename_count, dirs_removed,
+ rename_dst[i].p->one->path,
+ rename_dst[i].p->two->path);
+ }
+}
+
static void initialize_dir_rename_info(struct dir_rename_info *info)
{
int i;
@@ -790,7 +913,9 @@ static void remove_unneeded_paths_from_src(int detecting_copies)
rename_src_nr = new_num_src;
}
-void diffcore_rename(struct diff_options *options)
+void diffcore_rename_extended(struct diff_options *options,
+ struct strset *dirs_removed,
+ struct strmap *dir_rename_count)
{
int detect_rename = options->detect_rename;
int minimum_score = options->rename_score;
@@ -805,6 +930,7 @@ void diffcore_rename(struct diff_options *options)
trace2_region_enter("diff", "setup", options->repo);
info.setup = 0;
+ assert(!dir_rename_count || strmap_empty(dir_rename_count));
want_copies = (detect_rename == DIFF_DETECT_COPY);
if (!minimum_score)
minimum_score = DEFAULT_RENAME_SCORE;
@@ -999,6 +1125,11 @@ void diffcore_rename(struct diff_options *options)
trace2_region_leave("diff", "inexact renames", options->repo);
cleanup:
+ /*
+ * Now that renames have been computed, compute dir_rename_count */
+ if (dirs_removed && dir_rename_count)
+ compute_dir_rename_counts(dir_rename_count, dirs_removed);
+
/* At this point, we have found some renames and copies and they
* are recorded in rename_dst. The original list is still in *q.
*/
@@ -1082,3 +1213,8 @@ void diffcore_rename(struct diff_options *options)
trace2_region_leave("diff", "write back to queue", options->repo);
return;
}
+
+void diffcore_rename(struct diff_options *options)
+{
+ diffcore_rename_extended(options, NULL, NULL);
+}
