documents: an empty visual document opens its end on focus

Typing in a new file lands with no press.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/documents/document/edit.rs

@@ -5,6 +5,7 @@ use gpui::{AppContext as _, Context, Focusable as _, Window};
 use super::{DocumentEvent, MarkdownDocument, Open};
 use crate::{
     documents::{
+        MarkdownMode,
         markdown::markdown_highlights,
         modes::{at_edge, joint},
     },
@@ -22,6 +23,14 @@ fn moved(at: usize, edit: &Option<(Range<usize>, usize)>) -> Option<usize> {
 }
 
 impl MarkdownDocument {
+    /// An empty visual document takes typing at once.
+    pub(super) fn focused(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        let empty = self.editor.read(cx).text().trim().is_empty();
+        if self.mode == MarkdownMode::Visual && self.open.is_none() && empty {
+            self.open(None, false, window, cx);
+        }
+    }
+
     /// Opens block `ix` as shown, or one past the end.
     pub(super) fn open(
         &mut self,

src/documents/document/mod.rs

@@ -105,11 +105,15 @@ impl MarkdownDocument {
                 .hide_indent_guides()
                 .highlighter(markdown_highlights)
         });
-        let subscriptions = vec![cx.subscribe(&editor, |document, _, event, cx| {
-            if *event == EditorEvent::Changed {
-                document.changed(cx);
-            }
-        })];
+        let focus = cx.focus_handle();
+        let subscriptions = vec![
+            cx.subscribe(&editor, |document, _, event, cx| {
+                if *event == EditorEvent::Changed {
+                    document.changed(cx);
+                }
+            }),
+            cx.on_focus(&focus, window, Self::focused),
+        ];
         let overdraw = window.rem_size() * 40.0;
         let mut document = Self {
             editor,
@@ -123,7 +127,7 @@ impl MarkdownDocument {
             top: None,
             asks: 0,
             writes: 0,
-            focus: cx.focus_handle(),
+            focus,
             on_link: None,
             _subscriptions: subscriptions,
         };

src/documents/document/tests/mod.rs

@@ -397,3 +397,31 @@ fn a_text_past_the_largest_read_is_never_read(cx: &mut TestAppContext) {
     });
     assert_eq!((blocks, outline), (0, 0), "the old read is gone");
 }
+
+/// Focus on `document`'s own handle, as an owner gives it.
+fn focus(document: &Entity<MarkdownDocument>, cx: &mut VisualTestContext) {
+    let handle = document.read_with(cx, |document, cx| {
+        gpui::Focusable::focus_handle(document, cx)
+    });
+    cx.update(|window, cx| window.focus(&handle, cx));
+    cx.run_until_parked();
+}
+
+#[gpui::test]
+fn an_empty_visual_document_takes_typing_on_focus(cx: &mut TestAppContext) {
+    let (document, cx) = open("", MarkdownMode::Visual, cx);
+    focus(&document, cx);
+    cx.simulate_input("Hi");
+    assert_eq!(text(&document, cx), "Hi", "typing lands with no press");
+    cx.simulate_keystrokes("escape");
+    cx.run_until_parked();
+    assert_eq!(text(&document, cx), "Hi", "escape keeps it");
+}
+
+#[gpui::test]
+fn focus_opens_no_block_in_a_written_document(cx: &mut TestAppContext) {
+    let (document, cx) = open(TEXT, MarkdownMode::Visual, cx);
+    focus(&document, cx);
+    cx.simulate_input("x");
+    assert_eq!(text(&document, cx), TEXT);
+}