get_worktrees() must return main worktree as first item even on error

This is required by git-worktree.txt, stating that the main worktree is
the first line (especially in --porcelain mode when we can't just change
behavior at will).

There's only one case when get_worktrees() may skip main worktree, when
parse_ref() fails. Update the code so that we keep first item as main
worktree and return something sensible in this case:

- In user-friendly mode, since we're not constraint by anything,
returning "(error)" should do the job (we already show "(detached
HEAD)" which is not machine-friendly). Actually errors should be
printed on stderr by parse_ref() (*)

- In plumbing mode, we do not show neither 'bare', 'detached' or
'branch ...', which is possible by the format description if I read
it right.

Careful readers may realize that when the local variable "head_ref" in
get_main_worktree() is emptied, add_head_info() will do nothing to
wt->head_sha1. But that's ok because head_sha1 is zero-ized in the
previous patch.

(*) Well, it does not. But it's supposed to be a stop gap implementation
until we can reuse refs code to parse "ref: " stuff in HEAD, from
resolve_refs_unsafe(). Now may be the time since refs refactoring is
mostly done.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/worktree.c b/builtin/worktree.c
index 8a654e4ad3ee8d830e9271f13ae2335528a1d1b7..b835b91f636b02923eb0b113f10794a57008a463 100644 (file)
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -388,7 +388,7 @@ static void show_worktree_porcelain(struct worktree *wt)
                printf("HEAD %s\n", sha1_to_hex(wt->head_sha1));
                if (wt->is_detached)
                        printf("detached\n");
-               else
+               else if (wt->head_ref)
                        printf("branch %s\n", wt->head_ref);
        }
        printf("\n");
@@ -408,8 +408,10 @@ static void show_worktree(struct worktree *wt, int path_maxlen, int abbrev_len)
                                find_unique_abbrev(wt->head_sha1, DEFAULT_ABBREV));
                if (wt->is_detached)
                        strbuf_addstr(&sb, "(detached HEAD)");
-               else
+               else if (wt->head_ref)
                        strbuf_addf(&sb, "[%s]", shorten_unambiguous_ref(wt->head_ref, 0));
+               else
+                       strbuf_addstr(&sb, "(error)");
        }
        printf("%s\n", sb.buf);
 

diff --git a/t/t2027-worktree-list.sh b/t/t2027-worktree-list.sh
index 1b1b65a6b0fc7ace4e18e8642a6c47631d7e6a43..98b5f340e5b58136dea9a6a89f5d78295e902801 100755 (executable)
--- a/t/t2027-worktree-list.sh
+++ b/t/t2027-worktree-list.sh
@@ -96,4 +96,25 @@ test_expect_success 'bare repo cleanup' '
        rm -rf bare1
 '
 
+test_expect_success 'broken main worktree still at the top' '
+       git init broken-main &&
+       (
+               cd broken-main &&
+               test_commit new &&
+               git worktree add linked &&
+               cat >expected <<-EOF &&
+               worktree $(pwd)
+               HEAD $_z40
+
+               EOF
+               cd linked &&
+               echo "worktree $(pwd)" >expected &&
+               echo "ref: .broken" >../.git/HEAD &&
+               git worktree list --porcelain | head -n 3 >actual &&
+               test_cmp ../expected actual &&
+               git worktree list | head -n 1 >actual.2 &&
+               grep -F "(error)" actual.2
+       )
+'
+
 test_done

diff --git a/worktree.c b/worktree.c
index f7c1b5e24de237341f1228961bf35885c01f1583..3145522536bea8d1084f15fd24fc889181df88d2 100644 (file)
--- a/worktree.c
+++ b/worktree.c
@@ -88,16 +88,13 @@ static struct worktree *get_main_worktree(void)
 
        strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
 
-       if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
-               goto done;
-
        worktree = xcalloc(1, sizeof(*worktree));
        worktree->path = strbuf_detach(&worktree_path, NULL);
        worktree->is_bare = is_bare;
        worktree->is_detached = is_detached;
-       add_head_info(&head_ref, worktree);
+       if (!parse_ref(path.buf, &head_ref, &is_detached))
+               add_head_info(&head_ref, worktree);
 
-done:
        strbuf_release(&path);
        strbuf_release(&worktree_path);
        strbuf_release(&head_ref);
@@ -173,8 +170,7 @@ struct worktree **get_worktrees(void)
 
        list = xmalloc(alloc * sizeof(struct worktree *));
 
-       if ((list[counter] = get_main_worktree()))
-               counter++;
+       list[counter++] = get_main_worktree();
 
        strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
        dir = opendir(path.buf);