support tmux switching operation in /mux command (#1)

Author: 0WD0

README.md

@@ -32,7 +32,7 @@ Fork your current session at any previous message, the original stays open.
 
 ### `/mux`
 
-Lists every Pi running on your machine. Kill the ones you're done with.
+Lists every Pi running on your machine. Press Enter to jump to an open Pi or bring a backgrounded one forward; kill the ones you're done with.
 
 Each row shows cwd, session name, and a tag:
 

src/index.ts

@@ -12,7 +12,7 @@ type SessionManagerLike = {
   getBranch(): ReturnType<SessionManager["getBranch"]>;
 };
 import * as heartbeat from "./heartbeat.js";
-import { MuxMenu } from "./mux-menu.js";
+import { MuxMenu, type MuxMenuSelection } from "./mux-menu.js";
 import { spawnAndSwap } from "./swap.js";
 
 const SELF = fileURLToPath(import.meta.url);
@@ -407,25 +407,38 @@ export default function (pi: ExtensionAPI) {
   });
 
   pi.registerCommand("mux", {
-    description: "List and manage backgrounded pi-mux sessions",
+    description: "List, switch, and manage pi-mux sessions",
     handler: async (_args, ctx) => {
       if (!inTmux()) {
         ctx.ui.notify("not in tmux", "error");
         return;
       }
       const self = process.env.TMUX_PANE!;
       const cwd = ctx.cwd;
-      await ctx.ui.custom<undefined>((tui, theme, _keybindings, done) => {
-        const menu = new MuxMenu({
-          tui,
-          theme,
-          currentPaneId: self,
-          currentCwd: cwd,
-          done,
-        });
-        tui.setFocus(menu);
-        return menu;
-      });
+      const picked = await ctx.ui.custom<MuxMenuSelection | undefined>(
+        (tui, theme, _keybindings, done) => {
+          const menu = new MuxMenu({
+            tui,
+            theme,
+            currentPaneId: self,
+            currentCwd: cwd,
+            done,
+          });
+          tui.setFocus(menu);
+          return menu;
+        },
+      );
+
+      if (!picked || picked.paneId === self) return;
+      try {
+        if (picked.inPool) {
+          execFileSync("tmux", ["swap-pane", "-s", picked.paneId, "-t", self]);
+        } else {
+          execFileSync("tmux", ["switch-client", "-t", picked.paneId]);
+        }
+      } catch {
+        ctx.ui.notify("failed to switch session", "error");
+      }
     },
   });
 }

src/mux-menu.ts

@@ -25,12 +25,17 @@ interface TreeRow {
   ancestorContinues: boolean[];
 }
 
+export interface MuxMenuSelection {
+  paneId: string;
+  inPool: boolean;
+}
+
 export interface MuxMenuOptions {
   tui: TUI;
   theme: Theme;
   currentPaneId: string;
   currentCwd: string;
-  done: (result: undefined) => void;
+  done: (result: MuxMenuSelection | undefined) => void;
 }
 
 export class MuxMenu extends Container implements Focusable {
@@ -44,7 +49,7 @@ export class MuxMenu extends Container implements Focusable {
   private readonly theme: Theme;
   private readonly currentPaneId: string;
   private readonly currentCwd: string;
-  private readonly done: (result: undefined) => void;
+  private readonly done: (result: MuxMenuSelection | undefined) => void;
   private refreshTimer?: ReturnType<typeof setInterval>;
   private poolPanes = new Set<string>();
   private readonly list: MuxList;
@@ -135,7 +140,16 @@ export class MuxMenu extends Container implements Focusable {
       this.handleConfirmInput(data);
       return;
     }
-    if (data === "\r" || data === "\n" || data === "\u001b" || data === "q") {
+    if (data === "\r" || data === "\n") {
+      const row = this.selectedRow();
+      if (!row || row.paneId === this.currentPaneId) {
+        this.done(undefined);
+        return;
+      }
+      this.done({ paneId: row.paneId, inPool: this.poolPanes.has(row.paneId) });
+      return;
+    }
+    if (data === "\u001b" || data === "q") {
       this.done(undefined);
       return;
     }
@@ -260,6 +274,7 @@ class MuxList implements Component {
     } else {
       const sep = theme.fg("muted", " · ");
       const hints = [
+        rawKeyHint("enter", "switch"),
         rawKeyHint("d", "kill"),
         rawKeyHint("D", "kill all"),
         rawKeyHint("tab", "scope"),