A new terminal's greeting `ls` goes at its shell's first prompt or never

The greeting waited for any moment the cursor sat at a prompt's input, so
where the first prompt was missed (a resize still pending, a line written
before it), `ls` was typed later into whatever ran then. It is now sent
only while nothing has run (pardes's marks saw no command start) and
nothing is typed at the prompt; past that it is dropped, never typed late.
A prompt drawn again for a resize is still the first.

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

1 files changed, 21 insertions, 0 deletions

diff --git a/src/Terminal.zig b/src/Terminal.zig
index 4808298e..32595d25 100644
--- a/src/Terminal.zig
+++ b/src/Terminal.zig
@@ -1013,6 +1013,27 @@ pub fn onAlternateScreen(pane: *const Pane) bool {
     return state.vt.screens.active_key == .alternate;
 }
 
+/// Whether a new terminal's greeting may be typed now: only at the shell's
+/// first prompt (pardes's own marks: no command started; a prompt drawn
+/// again for a resize is the same first prompt), with nothing
+/// typed at it and no program on the alternate screen. Any later moment is `.never`, for good: something has run or
+/// been typed first, and an `ls` then would go into it. A shell pardes
+/// cannot mark has no first prompt to find, and is never greeted.
+pub fn greeting(pane: *const Pane) enum { wait, now, never } {
+    if (comptime !enabled) return .never;
+    if (pane.fs.unmarked) return .never;
+    // Text typed into the edit buffer that stands in for the prompt row.
+    if (pane.ovl) |o| if (o.text.len > 0) return .never;
+    const state = pane.terminal orelse return .wait;
+    const marks = &state.stream.handler;
+    // (Not `declined`: bash's first prompt comes after a D of its own.)
+    if (marks.started > 0) return .never;
+    // At a prompt's input (ghostty's semantic marks, pardes's or the
+    // shell's own), before any command pardes's marks saw run.
+    if (!promptInputReady(pane)) return .wait;
+    return if (promptInputEmpty(pane)) .now else .never;
+}
+
 pub fn promptInputReady(pane: *const Pane) bool {
     if (comptime !enabled) return false;
     const state = pane.terminal orelse return false;