1 files changed, 39 insertions, 10 deletions
diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index 403100f2..e7274c5e 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -331,13 +331,13 @@ fn writeQuoted(w: *std.Io.Writer, s: []const u8) !void {
     try w.writeByte('\'');
 }
 
-pub const pane_text_cap = 7 * 12 + 2 * 256 + 4 + "notcurrent ".len + 48;
+pub const pane_text_cap = 9 * 12 + 2 * 256 + 4 + "notcurrent ".len + 48;
 
-/// acme's winctlprint: serial, tag length, body length, a reserved zero, the
-/// dirty flag, then the width in cells, the font and the tab width. Then
-/// rio's word for whether the window has the keyboard, `current` or
-/// `notcurrent` (rio(4), wctl), which acme's line has no room for because
-/// acme has one window for input at a time only by the mouse.
+/// acme's winctlprint (plan9port wind.c), field for field: serial, tag
+/// length, body length, isdir (0), the dirty flag, the width in cells, the
+/// font, the tab width, whether Undo has a step, whether Redo has one. Then
+/// pardes's own: rio's word for whether the window has the keyboard,
+/// `current` or `notcurrent` (rio(4), wctl), and a REPL's id.
 pub fn paneText(p: *Pardes, pane: *Pane, buf: []u8) []const u8 {
     var w = std.Io.Writer.fixed(buf);
     w.print("{d:>11} {d:>11} {d:>11} {d:>11} {d:>11} {d:>11} ", .{
@@ -353,7 +353,10 @@ pub fn paneText(p: *Pardes, pane: *Pane, buf: []u8) []const u8 {
     writeQuoted(&w, if (font.len == 0) "default" else font) catch return w.buffered();
     // While a column's or the workspace's tag has the keyboard, no pane does.
     const current = p.panes[p.active] == pane and !p.header_focus;
-    w.print(" {d:>11} {s} ", .{ config.tab_width, if (current) "current" else "notcurrent" }) catch {};
+    const f = pane_files.fileOf(pane);
+    const undo = if (f) |file| file.history.undo_len > 0 else false;
+    const redo = if (f) |file| file.history.redo_len > 0 else false;
+    w.print(" {d:>11} {d:>11} {d:>11} {s} ", .{ config.tab_width, @intFromBool(undo), @intFromBool(redo), if (current) "current" else "notcurrent" }) catch {};
     // A terminal bound as a REPL ends with its id, `python-a`.
     var idbuf: [48]u8 = undefined;
     const id = exec_line.replId(&idbuf, pane);
@@ -1004,7 +1007,7 @@ const root_status = @intFromEnum(tree.TopFile.status);
 const root_look = @intFromEnum(tree.TopFile.look);
 const root_exec = @intFromEnum(tree.TopFile.exec);
 
-test "pane ctl read is index's five fields plus width in cells, font, tab width and whether it is current" {
+test "pane ctl read is acme's fields -- index's five, width in cells, font, tab width, undo, redo -- then whether it is current" {
     const gpa = testing.allocator;
     const p = try withFile(gpa, "x\n");
     defer p.deinit();
@@ -1014,8 +1017,8 @@ test "pane ctl read is index's five fields plus width in cells, font, tab width
     try testing.expectEqual(Status.ok, a.reply.status);
     var want: std.ArrayList(u8) = .empty;
     defer want.deinit(gpa);
-    try want.print(gpa, "{d:>11} {d:>11} {d:>11} {d:>11} {d:>11} {d:>11} {s} {d:>11} current ", .{
-        pane.serial, pane_files.tagOf(p, pane).len, @as(usize, 2), 0, 0, pane.cols, "default", config.tab_width,
+    try want.print(gpa, "{d:>11} {d:>11} {d:>11} {d:>11} {d:>11} {d:>11} {s} {d:>11} {d:>11} {d:>11} current ", .{
+        pane.serial, pane_files.tagOf(p, pane).len, @as(usize, 2), 0, 0, pane.cols, "default", config.tab_width, 0, 0,
     });
     try testing.expectEqualStrings(want.items, a.bytes);
     try testing.expectEqual(@as(u64, a.bytes.len), call(p, .{ .tag = 1, .op = .getattr, .node = Node.of(pane.serial, .ctl) }).reply.attr.size);
@@ -2399,6 +2402,32 @@ test "a pane's ctl takes acme's words: done by the files that replace them, or r
     try testing.expectEqualStrings("0", std.mem.trimEnd(u8, rd(p, Node.of(serial, .dirty), 0, 8).bytes, "\n"));
 }
 
+test "ctl reads acme's fields in acme's order, undo and redo flags included, then pardes's own" {
+    const p = try withFile(testing.allocator, "one\n");
+    defer p.deinit();
+    const serial = serialOf(p);
+    const ctl_node = Node.of(serial, .ctl);
+    const fields = struct {
+        fn of(text: []const u8, buf: *[16][]const u8) [][]const u8 {
+            var it = std.mem.tokenizeScalar(u8, text, ' ');
+            var n: usize = 0;
+            while (it.next()) |t| : (n += 1) buf[n] = t;
+            return buf[0..n];
+        }
+    };
+    var buf: [16][]const u8 = undefined;
+    var f = fields.of(rd(p, ctl_node, 0, 4096).bytes, &buf);
+    try testing.expectEqualStrings("0", f[8]); // nothing to undo
+    try testing.expectEqualStrings("0", f[9]); // nothing to redo
+    try testing.expect(std.mem.eql(u8, f[10], "current") or std.mem.eql(u8, f[10], "notcurrent"));
+    _ = wr(p, Node.of(serial, .body), "two\n");
+    f = fields.of(rd(p, ctl_node, 0, 4096).bytes, &buf);
+    try testing.expectEqualStrings("1", f[8]);
+    _ = wr(p, ctl_node, "Undo\n");
+    f = fields.of(rd(p, ctl_node, 0, 4096).bytes, &buf);
+    try testing.expectEqualStrings("1", f[9]);
+}
+
 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();