Live read-side sync between Warp and OS shell history files (#3422)

app/src/lib.rs

@@ -1441,6 +1441,7 @@ fn initialize_app(
         } else {
             log::info!("Home directory not found; skipping HomeDirectoryWatcher registration");
         }
+        ctx.add_singleton_model(crate::terminal::shell_history_watcher::ShellHistoryWatcher::new);
     }
 
     #[cfg(feature = "local_fs")]
@@ -1494,6 +1495,15 @@ fn initialize_app(
 
     ctx.add_singleton_model(move |_| History::new(command_history));
 
+    // GH-3422: subscribe History to ShellHistoryWatcher so live updates from
+    // other terminals (when the user has opted in via
+    // `terminal.live_sync_os_shell_history`) flow into Warp's autocomplete.
+    // Idempotent — safe to call once at app startup.
+    #[cfg(not(target_family = "wasm"))]
+    crate::terminal::history::History::handle(ctx).update(ctx, |history, ctx| {
+        history.set_up_external_history_sync(ctx);
+    });
+
     ctx.add_singleton_model(CustomSecretRegexUpdater::new);
 
     // Register the `TelemetryCollection` singleton model.

app/src/search/command_search/view.rs

@@ -339,6 +339,12 @@ impl CommandSearchView {
                                 ctx.notify();
                             }
                         }
+                        HistoryEvent::ExternalHistoryUpdated { .. } => {
+                            // Live OS-shell-history sync (GH-3422). The mixer's
+                            // history source re-queries on its own debounce, so
+                            // we just trigger a notify to refresh visible state.
+                            ctx.notify();
+                        }
                     }
                 });
             }

app/src/settings/init.rs

@@ -38,8 +38,8 @@ use super::{
     AliasExpansionSettings, AppEditorSettings, BlockVisibilitySettings, ChangelogSettings,
     CodeSettings, DebugSettings, EmacsBindingsSettings, FontSettings, FontSettingsChangedEvent,
     GPUSettings, InputBoxType, InputModeSettings, InputSettings, PaneSettings,
-    SameLinePromptBlockSettings, ScrollSettings, SelectionSettings, SshSettings, ThemeSettings,
-    VimBannerSettings, WarpDrivePrivacySettings,
+    SameLinePromptBlockSettings, ScrollSettings, SelectionSettings, ShellHistorySyncSettings,
+    SshSettings, ThemeSettings, VimBannerSettings, WarpDrivePrivacySettings,
 };
 
 pub struct UserDefaultsOnStartup {
@@ -91,6 +91,7 @@ pub fn register_all_settings(ctx: &mut AppContext) {
     AltScreenReporting::register(ctx);
     UndoCloseSettings::register(ctx);
     SshSettings::register(ctx);
+    ShellHistorySyncSettings::register(ctx);
     VimBannerSettings::register(ctx);
     SharedSessionSettings::register(ctx);
     WarpDriveSettings::register(ctx);

app/src/settings/mod.rs

@@ -29,6 +29,7 @@ mod privacy;
 mod same_line_prompt_block;
 mod scroll;
 mod select;
+mod shell_history_sync;
 mod ssh;
 mod theme;
 mod vim_banner;
@@ -61,6 +62,7 @@ pub use privacy::*;
 pub use same_line_prompt_block::*;
 pub use scroll::*;
 pub use select::*;
+pub use shell_history_sync::*;
 pub use ssh::*;
 pub use theme::*;
 pub use vim_banner::*;

app/src/settings/shell_history_sync.rs

@@ -0,0 +1,18 @@
+use settings::{
+    macros::define_settings_group, RespectUserSyncSetting, SupportedPlatforms, SyncToCloud,
+};
+
+define_settings_group!(ShellHistorySyncSettings, settings: [
+    live_sync_os_shell_history: LiveSyncOsShellHistoryEnabled {
+        type: bool,
+        default: false,
+        supported_platforms: SupportedPlatforms::ALL,
+        sync_to_cloud: SyncToCloud::Globally(RespectUserSyncSetting::Yes),
+        private: false,
+        toml_path: "terminal.live_sync_os_shell_history",
+        description: "When enabled, Warp watches the active shell's history file (~/.zsh_history, \
+                      ~/.bash_history, fish, PSReadLine) for changes made by other terminals and \
+                      merges new commands into Warp's autocomplete in real time. Off by default. \
+                      Tracks GH-3422.",
+    },
+]);