The jump list never holds two entries in a row the same: when the one between them goes, they are one

A closed pane's entry dropped from between two visits to the same place,
or a closed file's entry reopened beside its own, left twin entries,
and Back spent a press going nowhere while Jumplist listed the place
twice. The compaction that drops dead entries now folds a twin into the
one before it, keeping the current entry on the one kept.

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

1 files changed, 26 insertions, 0 deletions

diff --git a/src/pardes.zig b/src/pardes.zig
index f08cf01b..6a78c115 100644
--- a/src/pardes.zig
+++ b/src/pardes.zig
@@ -6889,6 +6889,12 @@ pub const Pardes = struct {
                     break;
                 };
             }
+            // Two in a row the same (a closed one reopened beside its own,
+            // or the entry between them gone): one entry, one step.
+            if (w > 0 and std.meta.eql(p.jumps[w - 1], kept)) {
+                if (i == p.jcur) cur = w - 1;
+                continue;
+            }
             p.jumps[w] = kept;
             w += 1;
         }
@@ -8034,6 +8040,26 @@ test "raw tty Ctrl-B switches to editor mode without sending child input" {
     try std.testing.expectEqualStrings("", drainWrites(p, &buf));
 }
 
+test "the jump list never holds two entries in a row the same, when the one between them goes" {
+    const p = try Pardes.init(std.testing.allocator, .{ .cols = 60, .rows = 40 });
+    defer p.deinit();
+    const pane = try p.setTestFile("a\n" ** 200);
+    const at: Loc = .{ .pane = 0, .serial = pane.serial, .line = 1, .col = 1 };
+    // A, a pane long closed with no file to keep it, A again, then far on.
+    p.jumps[0] = at;
+    p.jumps[1] = .{ .pane = 5, .serial = 999, .line = 1, .col = 1 };
+    p.jumps[2] = at;
+    p.jumps[3] = .{ .pane = 0, .serial = pane.serial, .line = 150, .col = 1 };
+    p.njumps = 4;
+    p.jcur = 3;
+    pane.body.cur_row = 80; // where you are now: far from both
+    p.trackJump();
+    for (1..p.njumps) |i| try std.testing.expect(!std.meta.eql(p.jumps[i - 1], p.jumps[i]));
+    try std.testing.expectEqual(@as(usize, 3), p.njumps);
+    try std.testing.expectEqual(@as(u32, 1), p.jumps[0].line);
+    try std.testing.expectEqual(@as(u32, 150), p.jumps[1].line);
+}
+
 test "hopping between two panes does not grow the jump stack" {
     if (platform == .web) return;
     const gpa = std.testing.allocator;