A buffer whose file was deleted on disk is dirty, and Del asks first

A file deleted under an open buffer left dirty 0 and let Del, Exit and the rest throw the only copy of its text away unasked. It now counts as dirty, as acme's does, and the refusals ask about it.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index b93d83c3..ebb85609 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -2201,6 +2201,20 @@ test "+Unsaved drops a pane once it has closed" {
     try testing.expect(std.mem.indexOf(u8, list.file.?.content, "/tmp/pardes-unsaved-a.txt: Modified") == null);
 }
 
+test "a buffer whose file was deleted on disk is dirty, and Del asks first" {
+    const p = try withFile(testing.allocator, "x\n");
+    defer p.deinit();
+    const serial = serialOf(p);
+    try testing.expectEqualStrings("0", std.mem.trimEnd(u8, rd(p, Node.of(serial, .dirty), 0, 8).bytes, "\n"));
+    pardes.panes.File.deleted(p, @intCast(p.paneBySerial(serial).?));
+    try testing.expectEqualStrings("1", std.mem.trimEnd(u8, rd(p, Node.of(serial, .dirty), 0, 8).bytes, "\n"));
+    try testing.expectEqual(Status.err, wr(p, Node.of(serial, .ctl), "Del\n").reply.status);
+    try testing.expect(p.paneBySerial(serial) != null);
+    _ = wr(p, Node.of(serial, .ctl), "Del\n");
+    p.sync();
+    try testing.expect(p.paneBySerial(serial) == null);
+}
+
 test "every EINVAL a write gets says why, in its err record too; DEL is a control character in a line" {
     const p = try withFile(testing.allocator, "x\n");
     defer p.deinit();