Rather than fatal error, report the "worktree already locked" message to
the diff view if a worktree diff has been selected or refreshed when the
work tree is busy. To reproduce and see the improved behaviour, perform
the following in a dirty work tree invoking tog with and without the
below diff applied:

$ tog
^z
$ got commit
^z
$ fg %1
# press `return' on the work tree entry


commit 70df4b3021cd5b9da8fc154219cb5ca17a7c8905 (main)
from: Mark Jamsek <mark@jamsek.dev>
date: Sun Dec  8 00:49:02 2024 UTC

tog worktree diff: don't fatal error if worktree is busy

Report the "worktree already locked" message to the view like we do in
corresponding command line situations.

M  tog/tog.c  |  19+  5-

1 file changed, 19 insertions(+), 5 deletions(-)

commit - cb83367306af4e956036c78dfcbb556adfa8adc9
commit + 70df4b3021cd5b9da8fc154219cb5ca17a7c8905
blob - 16256a8af275d99da1e2a192df7aa03132f49e5b
blob + 2ce26fea02651c5c22189e43095204197b89c0d7
--- tog/tog.c
+++ tog/tog.c
@@ -6363,9 +6363,27 @@ tog_diff_worktree(struct tog_diff_view_state *s, FILE 
 	if (cwd == NULL)
 		return got_error_from_errno("getcwd");
 
+	err = add_line_metadata(lines, nlines, 0, GOT_DIFF_LINE_NONE);
+	if (err != NULL)
+		goto done;
+
 	err = got_worktree_open(&worktree, cwd, NULL);
-	if (err != NULL)
+	if (err != NULL) {
+		if (err->code == GOT_ERR_WORKTREE_BUSY) {
+			int n;
+
+			if ((n = fprintf(f, "%s\n", err->msg)) < 0) {
+				err = got_ferror(f, GOT_ERR_IO);
+				goto done;
+			}
+			err = add_line_metadata(lines, nlines, n,
+			    GOT_DIFF_LINE_META);
+			if (err != NULL)
+				goto done;
+			err = got_error(GOT_ERR_DIFF_NOCHANGES);
+		}
 		goto done;
+	}
 
 	err = got_object_id_str(&id_str,
 	    got_worktree_get_base_commit_id(worktree));
@@ -6393,10 +6411,6 @@ tog_diff_worktree(struct tog_diff_view_state *s, FILE 
 	arg.f2 = s->f2;
 	arg.outfile = f;
 
-	err = add_line_metadata(lines, nlines, 0, GOT_DIFF_LINE_NONE);
-	if (err != NULL)
-		goto done;
-
 	if (s->paths == NULL) {
 		err = got_pathlist_insert(NULL, &pathlist, "", NULL);
 		if (err != NULL)


-- 
Mark Jamsek <https://bsdbox.org>
GPG: F2FF 13DE 6A06 C471 CA80  E6E2 2930 DC66 86EE CF68