stash: optimize `get_untracked_files()` and `check_changes()`
authorPaul-Sebastian Ungureanu <ungureanupaulsebastian@gmail.com>
Mon, 25 Feb 2019 23:16:26 +0000 (23:16 +0000)
committerJunio C Hamano <gitster@pobox.com>
Thu, 7 Mar 2019 00:41:40 +0000 (09:41 +0900)
This commits introduces a optimization by avoiding calling the
same functions again. For example, `git stash push -u`
would call at some points the following functions:

 * `check_changes()` (inside `do_push_stash()`)
 * `do_create_stash()`, which calls: `check_changes()` and
`get_untracked_files()`

Note that `check_changes()` also calls `get_untracked_files()`.
So, `check_changes()` is called 2 times and `get_untracked_files()`
3 times.

The old function `check_changes()` now consists of two functions:
`get_untracked_files()` and `check_changes_tracked_files()`.

These are the call chains for `push` and `create`:

 * `push_stash()` -> `do_push_stash()` -> `do_create_stash()`

 * `create_stash()` -> `do_create_stash()`

To prevent calling the same functions over and over again,
`check_changes()` inside `do_create_stash()` is now placed
in the caller functions (`create_stash()` and `do_push_stash()`).
This way `check_changes()` and `get_untracked files()` are called
only one time.

Signed-off-by: Paul-Sebastian Ungureanu <ungureanupaulsebastian@gmail.com>
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/stash--helper.c

index 8e4e96e..4c51b58 100644 (file)
@@ -879,18 +879,17 @@ static int get_untracked_files(struct pathspec ps, int include_untracked,
 }
 
 /*
- * The return value of `check_changes()` can be:
+ * The return value of `check_changes_tracked_files()` can be:
  *
  * < 0 if there was an error
  * = 0 if there are no changes.
  * > 0 if there are changes.
  */
-static int check_changes(struct pathspec ps, int include_untracked)
+static int check_changes_tracked_files(struct pathspec ps)
 {
        int result;
        struct rev_info rev;
        struct object_id dummy;
-       struct strbuf out = STRBUF_INIT;
 
        /* No initial commit. */
        if (get_oid("HEAD", &dummy))
@@ -918,14 +917,25 @@ static int check_changes(struct pathspec ps, int include_untracked)
        if (diff_result_code(&rev.diffopt, result))
                return 1;
 
+       return 0;
+}
+
+/*
+ * The function will fill `untracked_files` with the names of untracked files
+ * It will return 1 if there were any changes and 0 if there were not.
+ */
+static int check_changes(struct pathspec ps, int include_untracked,
+                        struct strbuf *untracked_files)
+{
+       int ret = 0;
+       if (check_changes_tracked_files(ps))
+               ret = 1;
+
        if (include_untracked && get_untracked_files(ps, include_untracked,
-                                                    &out)) {
-               strbuf_release(&out);
-               return 1;
-       }
+                                                    untracked_files))
+               ret = 1;
 
-       strbuf_release(&out);
-       return 0;
+       return ret;
 }
 
 static int save_untracked_files(struct stash_info *info, struct strbuf *msg,
@@ -1137,7 +1147,7 @@ static int do_create_stash(struct pathspec ps, struct strbuf *stash_msg_buf,
                head_commit = lookup_commit(the_repository, &info->b_commit);
        }
 
-       if (!check_changes(ps, include_untracked)) {
+       if (!check_changes(ps, include_untracked, &untracked_files)) {
                ret = 1;
                goto done;
        }
@@ -1162,8 +1172,7 @@ static int do_create_stash(struct pathspec ps, struct strbuf *stash_msg_buf,
                goto done;
        }
 
-       if (include_untracked && get_untracked_files(ps, include_untracked,
-                                                    &untracked_files)) {
+       if (include_untracked) {
                if (save_untracked_files(info, &msg, untracked_files)) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot save "
@@ -1248,6 +1257,9 @@ static int create_stash(int argc, const char **argv, const char *prefix)
                             0);
 
        memset(&ps, 0, sizeof(ps));
+       if (!check_changes_tracked_files(ps))
+               return 0;
+
        strbuf_addstr(&stash_msg_buf, stash_msg);
        ret = do_create_stash(ps, &stash_msg_buf, include_untracked, 0, &info,
                              NULL, 0);
@@ -1255,12 +1267,7 @@ static int create_stash(int argc, const char **argv, const char *prefix)
                printf_ln("%s", oid_to_hex(&info.w_commit));
 
        strbuf_release(&stash_msg_buf);
-
-       /*
-        * ret can be 1 if there were no changes. In this case, we should
-        * not error out.
-        */
-       return ret < 0;
+       return ret;
 }
 
 static int do_push_stash(struct pathspec ps, const char *stash_msg, int quiet,
@@ -1270,6 +1277,7 @@ static int do_push_stash(struct pathspec ps, const char *stash_msg, int quiet,
        struct stash_info info;
        struct strbuf patch = STRBUF_INIT;
        struct strbuf stash_msg_buf = STRBUF_INIT;
+       struct strbuf untracked_files = STRBUF_INIT;
 
        if (patch_mode && keep_index == -1)
                keep_index = 1;
@@ -1304,7 +1312,7 @@ static int do_push_stash(struct pathspec ps, const char *stash_msg, int quiet,
                goto done;
        }
 
-       if (!check_changes(ps, include_untracked)) {
+       if (!check_changes(ps, include_untracked, &untracked_files)) {
                if (!quiet)
                        printf_ln(_("No local changes to save"));
                goto done;