worktree: don't die() in library function find_worktree()

Callers don't expect library function find_worktree() to die(); they
expect it to return the named worktree if found, or NULL if not.
Although find_worktree() itself never invokes die(), it calls
real_pathdup() with 'die_on_error' incorrectly set to 'true', thus will
die() indirectly if the user-provided path is not to real_pathdup()'s
liking. This can be observed, for instance, with any git-worktree
command which searches for an existing worktree:

$ git worktree unlock foo
fatal: 'foo' is not a working tree
$ git worktree unlock foo/bar
fatal: Invalid path '.../foo': No such file or directory

The first error message is the expected one from "git worktree unlock"
not finding the specified worktree; the second is from find_worktree()
invoking real_pathdup() incorrectly and die()ing prematurely.

Aside from the inconsistent error message between the two cases, this
bug hasn't otherwise been a serious problem since existing callers all
die() anyhow when the worktree can't be found. However, that may not be
true of callers added in the future, so fix find_worktree() to avoid
die()ing.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t2028-worktree-move.sh b/t/t2028-worktree-move.sh
index 5f7d45b7b7fa91a497d6f8d96a7235fc0024919e..60aba7c41ad3424b9a6cd1aba36360f90bd480b3 100755 (executable)
--- a/t/t2028-worktree-move.sh
+++ b/t/t2028-worktree-move.sh
@@ -141,4 +141,12 @@ test_expect_success 'NOT remove missing-but-locked worktree' '
        test_path_is_dir .git/worktrees/gone-but-locked
 '
 
+test_expect_success 'proper error when worktree not found' '
+       for i in noodle noodle/bork
+       do
+               test_must_fail git worktree lock $i 2>err &&
+               test_i18ngrep "not a working tree" err || return 1
+       done
+'
+
 test_done

diff --git a/worktree.c b/worktree.c
index 97cda5f97bbc10b2f5690b945ab42d2beef74e2e..b0d0b5426da0d1cbe8d7b6ff569c7511569cf0a3 100644 (file)
--- a/worktree.c
+++ b/worktree.c
@@ -217,7 +217,11 @@ struct worktree *find_worktree(struct worktree **list,
 
        if (prefix)
                arg = to_free = prefix_filename(prefix, arg);
-       path = real_pathdup(arg, 1);
+       path = real_pathdup(arg, 0);
+       if (!path) {
+               free(to_free);
+               return NULL;
+       }
        for (; *list; list++)
                if (!fspathcmp(path, real_path((*list)->path)))
                        break;