fix(mobile): coalesce keyboard viewport settling

test/mobile/keyboard.test.ts

@@ -323,6 +323,44 @@ describe('Virtual Keyboard', () => {
       expect(mainPadding).toBe('');
     });
 
+    it('coalesces keyboard animation frames into one final terminal fit', async () => {
+      const result = await page.evaluate(async () => {
+        const originalFit = app.fitAddon.fit.bind(app.fitAddon);
+        const originalSendResize = KeyboardHandler._sendTerminalResize.bind(KeyboardHandler);
+        const originalScrollToBottom = app.terminal.scrollToBottom.bind(app.terminal);
+        let fits = 0;
+        let resizes = 0;
+        let bottomRestores = 0;
+        app.fitAddon.fit = () => {
+          fits++;
+        };
+        KeyboardHandler._sendTerminalResize = () => {
+          resizes++;
+        };
+        app.terminal.scrollToBottom = () => {
+          bottomRestores++;
+        };
+
+        KeyboardHandler._scheduleViewportSettle({ scrollToBottom: true });
+        await new Promise((resolve) => setTimeout(resolve, 30));
+        KeyboardHandler._scheduleViewportSettle();
+        await new Promise((resolve) => setTimeout(resolve, 30));
+        KeyboardHandler._scheduleViewportSettle();
+        await new Promise((resolve) => setTimeout(resolve, 50));
+        const beforeFinalSettle = { fits, resizes, bottomRestores };
+        await new Promise((resolve) => setTimeout(resolve, KeyboardHandler.VIEWPORT_SETTLE_MS));
+        const afterFinalSettle = { fits, resizes, bottomRestores };
+
+        app.fitAddon.fit = originalFit;
+        KeyboardHandler._sendTerminalResize = originalSendResize;
+        app.terminal.scrollToBottom = originalScrollToBottom;
+        return { beforeFinalSettle, afterFinalSettle };
+      });
+
+      expect(result.beforeFinalSettle).toEqual({ fits: 0, resizes: 0, bottomRestores: 0 });
+      expect(result.afterFinalSettle).toEqual({ fits: 1, resizes: 1, bottomRestores: 1 });
+    });
+
     it('accessory bar has the simple-mode action buttons', async () => {
       const actions = await page.evaluate(() => {
         return Array.from(document.querySelectorAll('.keyboard-accessory-bar [data-action]')).map(