An undo step keeps no copy of the name: History keeps each name once, at the rename that ends it, and a step its generation, so typing allocates a snapshot and nothing more (follows prwqwwxt); a rename of one Zerox twin is logged for each twin

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

1 files changed, 2 insertions, 1 deletions

diff --git a/src/ninep/pane.zig b/src/ninep/pane.zig
index 981c2b0e..3b70d62f 100644
--- a/src/ninep/pane.zig
+++ b/src/ninep/pane.zig
@@ -982,7 +982,8 @@ pub fn nameBuffer(p: *Pardes, id: usize, full: []const u8, preserve_tag: bool) !
     if (std.mem.indexOfAny(u8, full, "\x00\n") != null) return error.InvalidName;
     if (std.mem.eql(u8, f.path, full)) return;
     const copy = try p.gpa.dupe(u8, full);
-    p.gpa.free(f.path);
+    // The name it ends is kept for an undo back across this rename.
+    panes.File.noteRenamed(p.gpa, f.history, f.path);
     f.path = copy;
     if (panes.Output.fileTraits(f.output).saves) {
         f.output = null;