Update workspace and app changes

packages/app/src/terminal/runtime/terminal-emulator-runtime.test.ts

@@ -196,4 +196,42 @@ describe("terminal-emulator-runtime", () => {
     expect(terminal.options?.theme).toEqual({ background: "after" });
     expect(refresh).toHaveBeenCalledWith(0, 11);
   });
+
+  it("forces a refit when the page becomes visible again", () => {
+    const runtime = new TerminalEmulatorRuntime();
+    const fitAndEmitResize = vi.fn();
+
+    (runtime as unknown as { fitAndEmitResize: (force: boolean) => void }).fitAndEmitResize =
+      fitAndEmitResize;
+    (globalThis as { document?: { visibilityState?: string } }).document = {
+      visibilityState: "visible",
+    };
+
+    (
+      runtime as unknown as {
+        handleVisibilityRestore: () => void;
+      }
+    ).handleVisibilityRestore();
+
+    expect(fitAndEmitResize).toHaveBeenCalledWith(true);
+  });
+
+  it("does not refit while the page is still hidden", () => {
+    const runtime = new TerminalEmulatorRuntime();
+    const fitAndEmitResize = vi.fn();
+
+    (runtime as unknown as { fitAndEmitResize: (force: boolean) => void }).fitAndEmitResize =
+      fitAndEmitResize;
+    (globalThis as { document?: { visibilityState?: string } }).document = {
+      visibilityState: "hidden",
+    };
+
+    (
+      runtime as unknown as {
+        handleVisibilityRestore: () => void;
+      }
+    ).handleVisibilityRestore();
+
+    expect(fitAndEmitResize).not.toHaveBeenCalled();
+  });
 });

packages/app/src/terminal/runtime/terminal-emulator-runtime.ts

@@ -36,6 +36,8 @@ type TerminalEmulatorRuntimeDisposables = {
   disposeInput: () => void;
   disconnectResizeObserver: () => void;
   removeWindowResize: () => void;
+  removeWindowFocus: () => void;
+  removeDocumentVisibilityChange: () => void;
   removeVisualViewportResize: () => void;
   clearFitInterval: () => void;
   clearFitTimeouts: () => void;
@@ -102,6 +104,19 @@ export class TerminalEmulatorRuntime {
   private inFlightOutputOperationTimeout: ReturnType<typeof setTimeout> | null = null;
   private suppressInput = false;
 
+  private handleVisibilityRestore = (): void => {
+    if (typeof document !== "undefined" && document.visibilityState !== "visible") {
+      return;
+    }
+
+    this.fitAndEmitResize?.(true);
+    if (typeof window.requestAnimationFrame === "function") {
+      window.requestAnimationFrame(() => {
+        this.fitAndEmitResize?.(true);
+      });
+    }
+  };
+
   setCallbacks(input: { callbacks: TerminalEmulatorRuntimeCallbacks }): void {
     this.callbacks = input.callbacks;
   }
@@ -311,6 +326,15 @@ export class TerminalEmulatorRuntime {
 
     const windowResizeHandler = () => fitAndEmitResize(false);
     window.addEventListener("resize", windowResizeHandler);
+    const windowFocusHandler = () => {
+      this.handleVisibilityRestore();
+    };
+    window.addEventListener("focus", windowFocusHandler);
+
+    const documentVisibilityChangeHandler = () => {
+      this.handleVisibilityRestore();
+    };
+    document.addEventListener("visibilitychange", documentVisibilityChangeHandler);
 
     const visualViewport = window.visualViewport;
     const visualViewportResizeHandler = () => fitAndEmitResize(false);
@@ -369,6 +393,12 @@ export class TerminalEmulatorRuntime {
       removeWindowResize: () => {
         window.removeEventListener("resize", windowResizeHandler);
       },
+      removeWindowFocus: () => {
+        window.removeEventListener("focus", windowFocusHandler);
+      },
+      removeDocumentVisibilityChange: () => {
+        document.removeEventListener("visibilitychange", documentVisibilityChangeHandler);
+      },
       removeVisualViewportResize: () => {
         visualViewport?.removeEventListener("resize", visualViewportResizeHandler);
       },
@@ -410,6 +440,8 @@ export class TerminalEmulatorRuntime {
       disposables.disposeInput();
       disposables.disconnectResizeObserver();
       disposables.removeWindowResize();
+      disposables.removeWindowFocus();
+      disposables.removeDocumentVisibilityChange();
       disposables.removeVisualViewportResize();
       disposables.clearFitInterval();
       disposables.clearFitTimeouts();