T18: Terminal: scrollback lines, Option as Alt on macOS, copy on select, each applied at once to every session; the settings pages share one switch and one segmented choice

src/settings/window/terminal.rs

@@ -0,0 +1,58 @@
+use ely_gpui_component::{
+    forms::NumberInput,
+    settings::{SettingsRow, SettingsSection},
+    theme::ControlSize,
+};
+use gpui::Context;
+
+use super::{SettingsWindow, choice, set, switch};
+use crate::settings::{OptionAsAlt, SCROLLBACK, SettingsStore};
+
+/// Each way Option types Alt, its key and its name.
+const OPTIONS: [(OptionAsAlt, &str, &str); 4] = [
+    (OptionAsAlt::Off, "off", "Off"),
+    (OptionAsAlt::Left, "left", "Left"),
+    (OptionAsAlt::Right, "right", "Right"),
+    (OptionAsAlt::Both, "both", "Both"),
+];
+
+impl SettingsWindow {
+    /// Scrollback, Option as Alt on macOS, and copy on select.
+    pub(super) fn terminal(&self, cx: &Context<Self>) -> SettingsSection {
+        let settings = SettingsStore::get(cx);
+        let this = cx.entity();
+        let lines = NumberInput::new(("scrollback", self.drafts), f64::from(settings.scrollback))
+            .range(f64::from(*SCROLLBACK.start()), f64::from(*SCROLLBACK.end()))
+            .step(1000.)
+            .size(ControlSize::Sm)
+            .on_commit({
+                let this = this.clone();
+                move |lines, _, cx| {
+                    let lines = lines as u32;
+                    set(&this, format!("scrollback is {lines}"), cx, |settings| {
+                        settings.scrollback = lines
+                    });
+                }
+            });
+        let mut section = SettingsSection::new("Terminal")
+            .row(SettingsRow::new("Scrollback lines").control(lines));
+        // Off macOS, Alt is always Alt.
+        if cfg!(target_os = "macos") {
+            let option = choice(
+                &this,
+                "option_as_alt",
+                &OPTIONS,
+                settings.option_as_alt,
+                |settings, option| settings.option_as_alt = option,
+            );
+            section = section.row(SettingsRow::new("Option as Alt").control(option));
+        }
+        let copy = switch(
+            &this,
+            "copy_on_select",
+            settings.copy_on_select,
+            |settings, on| settings.copy_on_select = on,
+        );
+        section.row(SettingsRow::new("Copy on select").control(copy))
+    }
+}