macos: fix dictation support, with new configs for preview text (#7453)

closes: #4592 & #5180

assets/macos/WezTerm.app/Contents/Info.plist

@@ -52,6 +52,8 @@
 	<string>An application launched via WezTerm would like to access your location information while active.</string>
 	<key>NSMicrophoneUsageDescription</key>
 	<string>An application launched via WezTerm would like to access your microphone.</string>
+	<key>NSSpeechRecognitionUsageDescription</key>
+	<string>An application launched via WezTerm would like to use speech recognition.</string>
 	<key>NSRemindersUsageDescription</key>
 	<string>An application launched via WezTerm would like to access your reminders.</string>
 	<key>NSDocumentsFolderUsageDescription</key>

config/src/color.rs

@@ -160,6 +160,10 @@ pub struct Palette {
     pub visual_bell: Option<RgbaColor>,
     /// The color to use for the cursor when a dead key or leader state is active
     pub compose_cursor: Option<RgbaColor>,
+    /// The foreground color for composition/IME preview text (e.g., dictation)
+    pub compose_fg: Option<RgbaColor>,
+    /// The background color for composition/IME preview text (e.g., dictation)
+    pub compose_bg: Option<RgbaColor>,
 
     pub copy_mode_active_highlight_fg: Option<ColorSpec>,
     pub copy_mode_active_highlight_bg: Option<ColorSpec>,
@@ -217,6 +221,8 @@ impl Palette {
             split: overlay!(split),
             visual_bell: overlay!(visual_bell),
             compose_cursor: overlay!(compose_cursor),
+            compose_fg: overlay!(compose_fg),
+            compose_bg: overlay!(compose_bg),
             copy_mode_active_highlight_fg: overlay!(copy_mode_active_highlight_fg),
             copy_mode_active_highlight_bg: overlay!(copy_mode_active_highlight_bg),
             copy_mode_inactive_highlight_fg: overlay!(copy_mode_inactive_highlight_fg),

docs/config/appearance.md

@@ -112,6 +112,15 @@ config.colors = {
   -- to this color to give a visual cue about the compose state.
   compose_cursor = 'orange',
 
+  -- Override the foreground color for composition/IME preview text,
+  -- such as text being dictated via macOS dictation or composed via
+  -- a dead key sequence. Falls back to the cursor foreground color.
+  compose_fg = '#1e1e2e', -- {{since('nightly', inline=True)}}
+
+  -- Override the background color for composition/IME preview text.
+  -- Falls back to the cursor background color.
+  compose_bg = '#f5c2e7', -- {{since('nightly', inline=True)}}
+
   -- Colors for copy_mode and quick_select
   -- available since: 20220807-113146-c2fee766
   -- In copy_mode, the color of the active text is:

wezterm-gui/src/termwindow/render/mod.rs

@@ -570,11 +570,32 @@ impl crate::TermWindow {
                 self.dead_key_status != DeadKeyStatus::None || self.leader_is_active();
 
             if dead_key_or_leader && params.is_active_pane {
-                let (fg_color, bg_color) = if self.use_reverse_video_cursor(&params) {
-                    (params.bg_color, params.fg_color)
-                } else {
-                    (params.cursor_fg, params.cursor_bg)
-                };
+                let (fg_color, bg_color) = (
+                    params
+                        .config
+                        .resolved_palette
+                        .compose_fg
+                        .map(|c| c.to_linear())
+                        .unwrap_or_else(|| {
+                            if self.use_reverse_video_cursor(&params) {
+                                params.bg_color
+                            } else {
+                                params.cursor_fg
+                            }
+                        }),
+                    params
+                        .config
+                        .resolved_palette
+                        .compose_bg
+                        .map(|c| c.to_linear())
+                        .unwrap_or_else(|| {
+                            if self.use_reverse_video_cursor(&params) {
+                                params.fg_color
+                            } else {
+                                params.cursor_bg
+                            }
+                        }),
+                );
 
                 let fg_color = self.ensure_min_contrast(fg_color, bg_color);
 

wezterm-gui/src/termwindow/render/screen_line.rs

@@ -303,6 +303,23 @@ impl crate::TermWindow {
             0.0..0.0
         };
 
+        // Render composition/IME preview background
+        if composition_width > 0 {
+            if let Some(compose_bg) = &params.config.resolved_palette.compose_bg {
+                let start = params.left_pixel_x + (params.cursor.x as f32 * cell_width);
+                let width = composition_width as f32 * cell_width;
+                let mut quad = self
+                    .filled_rectangle(
+                        layers,
+                        0,
+                        euclid::rect(start, params.top_pixel_y, width, cell_height),
+                        compose_bg.to_linear(),
+                    )
+                    .context("filled_rectangle")?;
+                quad.set_hsv(hsv);
+            }
+        }
+
         // Consider cursor
         if !cursor_range.is_empty() {
             let (fg_color, bg_color) = if let Some(c) = &cursor_cell {
@@ -736,7 +753,14 @@ impl crate::TermWindow {
             // Create an updated line with the composition overlaid
             let mut line = params.line.clone();
             let seqno = line.current_seqno();
-            line.overlay_text_with_attribute(*cursor_x, &composing, CellAttributes::blank(), seqno);
+
+            let mut compose_attrs = CellAttributes::blank();
+            if let Some(fg) = &params.config.resolved_palette.compose_fg {
+                compose_attrs
+                    .set_foreground(ColorAttribute::TrueColorWithDefaultFallback((*fg).into()));
+            }
+
+            line.overlay_text_with_attribute(*cursor_x, &composing, compose_attrs, seqno);
             line.cluster(bidi_hint)
         } else {
             params.line.cluster(bidi_hint)

window/src/os/macos/window.rs

@@ -2050,7 +2050,15 @@ impl WindowView {
     }
 
     extern "C" fn selected_range(_this: &mut Object, _sel: Sel) -> NSRange {
-        NSRange::new(NSNotFound as _, 0)
+        // Return an empty range at position 0 rather than {NSNotFound, 0}.
+        // NSTextInputClient expects character indices into a text storage
+        // buffer, but as a terminal emulator we don't maintain one—input
+        // is handled through insert_text/set_marked_text callbacks instead.
+        // Returning NSNotFound causes macOS dictation to silently bail out
+        // because it has no valid insertion point. An empty selection at 0
+        // satisfies the protocol and enables dictation. This is the same
+        // workaround used by kitty and Emacs. See #4592
+        NSRange::new(0, 0)
     }
 
     // Called by the IME when inserting composed text and/or emoji
@@ -2110,22 +2118,16 @@ impl WindowView {
             let mut inner = myself.inner.borrow_mut();
             inner.ime_text = s.to_string();
 
-            /*
-            let key_is_down = inner.key_is_down.take().unwrap_or(true);
+            // Show composition preview for dictation; see #4592
+            let status = if s.is_empty() {
+                DeadKeyStatus::None
+            } else {
+                DeadKeyStatus::Composing(s.to_string())
+            };
+            inner
+                .events
+                .dispatch(WindowEvent::AdviseDeadKeyStatus(status));
 
-            let key = KeyCode::composed(s);
-
-            let event = KeyEvent {
-                key,
-                modifiers: Modifiers::NONE,
-                repeat_count: 1,
-                key_is_down,
-            }
-            .normalize_shift();
-
-            inner.ime_last_event.replace(event.clone());
-            inner.events.dispatch(WindowEvent::KeyEvent(event));
-            */
             inner.ime_last_event.take();
             inner.ime_state = ImeDisposition::Acted;
         }
@@ -2141,6 +2143,9 @@ impl WindowView {
             inner.ime_text.clear();
             inner.ime_last_event.take();
             inner.ime_state = ImeDisposition::Acted;
+            inner
+                .events
+                .dispatch(WindowEvent::AdviseDeadKeyStatus(DeadKeyStatus::None));
         }
     }