An err record's reason that names its file already is not prefixed twice

A refused look logged `err N look: look: no space for a pane...`: the
reason began with the file's name, and the record put it before it again.

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

1 files changed, 3 insertions, 0 deletions

diff --git a/src/ninep/tree.zig b/src/ninep/tree.zig
index c089c31d..9d2027bf 100644
--- a/src/ninep/tree.zig
+++ b/src/ninep/tree.zig
@@ -1470,6 +1470,9 @@ test "at the pane cap, pane/new, look and New each say so, and look reads back e
     const looked = th.wr(p, look_node, try std.fmt.bufPrint(&line, "{s}/f.txt\n", .{dir}));
     try testing.expect(looked.errno() != 0);
     try testing.expect(std.mem.indexOf(u8, looked.reply.ename, said) != null);
+    // Its err record names the file once: `look: no space...`.
+    try testing.expect(th.logHas(p, "look: no space"));
+    try testing.expect(!th.logHas(p, "look: look:"));
     try testing.expectEqualStrings("", th.rd(p, look_node, 0, 64).bytes);
     // New from a pane's ctl fails as well.
     const ctl_node = Node.of(p.panes[0].?.serial, .ctl);