1 files changed, 31 insertions, 0 deletions
diff --git a/src/tty/tty.zig b/src/tty/tty.zig
index 23b7c09b..a1917ba9 100644
--- a/src/tty/tty.zig
+++ b/src/tty/tty.zig
@@ -71,6 +71,21 @@ fn inputReader(loop: *Loop, tty: anytype, cache: *vaxis.GraphemeCache) void {
     loop.postEvent(.quit) catch {};
 }
 
+/// How long a lone ESC waits for the rest of a sequence before it counts as
+/// the Escape key. Long enough for the remainder of a real sequence to arrive
+/// even over a slow link, short enough that nobody sees the delay.
+const escape_hold_ms = 25;
+
+/// Is there more input right behind what we have already read? Only a real
+/// terminal has an fd to ask; the test readers hand their parts over whole, so
+/// for them the answer is always no.
+fn morePending(tty: anytype) bool {
+    const Reader = @typeInfo(@TypeOf(tty)).pointer.child;
+    if (!@hasField(Reader, "fd") or @FieldType(Reader, "fd") != std.Io.File) return false;
+    var fds = [_]std.posix.pollfd{.{ .fd = tty.fd.handle, .events = std.posix.POLL.IN, .revents = 0 }};
+    return (std.posix.poll(&fds, escape_hold_ms) catch return false) > 0;
+}
+
 fn readInput(loop: *Loop, tty: anytype, cache: *vaxis.GraphemeCache) !void {
     try loop.postEvent(.{ .winsize = try tty.getWinsize() });
     var parser: vaxis.Parser = .{};
@@ -101,6 +116,22 @@ fn readInput(loop: *Loop, tty: anytype, cache: *vaxis.GraphemeCache) !void {
         }
         carried = end - consumed;
         std.mem.copyForwards(u8, buf[0..carried], buf[consumed..end]);
+        // A lone ESC opens most sequences and is also the Escape key, so the
+        // parser holds it for a remainder that a keypress never sends: the
+        // press would only land when the NEXT key arrived. Wait a beat, and
+        // when nothing follows it was the key. A terminal speaking the kitty
+        // protocol never reaches here — it spells Escape out in full.
+        if (carried == 1 and buf[0] == 0x1b and !morePending(tty)) {
+            carried = 0;
+            try vaxis.loop.handleEventGeneric(
+                loop,
+                loop.vaxis,
+                cache,
+                @TypeOf(Command.value),
+                @as(vaxis.Event, .{ .key_press = .{ .codepoint = vaxis.Key.escape } }),
+                loop.vaxis.opts.system_clipboard_allocator,
+            );
+        }
     }
 }