chore: don't let count() throw during navigation (#36941)

Author: Skn0tt

packages/playwright-core/src/client/frame.ts

@@ -247,8 +247,8 @@ export class Frame extends ChannelOwner<channels.FrameChannel> implements api.Fr
     return result.elements.map(e => ElementHandle.from(e) as ElementHandle<SVGElement | HTMLElement>);
   }
 
-  async _queryCount(selector: string): Promise<number> {
-    return (await this._channel.queryCount({ selector })).value;
+  async _queryCount(selector: string, options?: {}): Promise<number> {
+    return (await this._channel.queryCount({ selector, ...options })).value;
   }
 
   async content(): Promise<string> {

packages/playwright-core/src/client/locator.ts

@@ -249,8 +249,9 @@ export class Locator implements api.Locator {
     await this._frame._channel.blur({ selector: this._selector, strict: true, ...options, timeout: this._frame._timeout(options) });
   }
 
-  async count(): Promise<number> {
-    return await this._frame._queryCount(this._selector);
+  // options are only here for testing
+  async count(_options?: {}): Promise<number> {
+    return await this._frame._queryCount(this._selector, _options);
   }
 
   async _resolveSelector(): Promise<{ resolvedSelector: string }> {

packages/playwright-core/src/server/dispatchers/frameDispatcher.ts

@@ -117,7 +117,7 @@ export class FrameDispatcher extends Dispatcher<Frame, channels.FrameChannel, Br
   }
 
   async queryCount(params: channels.FrameQueryCountParams, progress: Progress): Promise<channels.FrameQueryCountResult> {
-    return { value: await progress.race(this._frame.queryCount(params.selector)) };
+    return { value: await progress.race(this._frame.queryCount(params.selector, params)) };
   }
 
   async content(params: channels.FrameContentParams, progress: Progress): Promise<channels.FrameContentResult> {

packages/playwright-core/src/server/frameSelectors.ts

@@ -75,11 +75,12 @@ export class FrameSelectors {
     }, { info: resolved.info, scope: resolved.scope });
   }
 
-  async queryCount(selector: string): Promise<number> {
+  async queryCount(selector: string, options: any): Promise<number> {
     const resolved = await this.resolveInjectedForSelector(selector);
     // Be careful, |this.frame| can be different from |resolved.frame|.
     if (!resolved)
       throw new Error(`Failed to find frame for selector "${selector}"`);
+    await options.__testHookBeforeQuery?.();
     return await resolved.injected.evaluate((injected, { info }) => {
       return injected.querySelectorAll(info.parsed, document).length;
     }, { info: resolved.info });

packages/playwright-core/src/server/frames.ts

@@ -841,8 +841,14 @@ export class Frame extends SdkObject {
     return this.selectors.queryAll(selector);
   }
 
-  async queryCount(selector: string): Promise<number> {
-    return await this.selectors.queryCount(selector);
+  async queryCount(selector: string, options: any): Promise<number> {
+    try {
+      return await this.selectors.queryCount(selector, options);
+    } catch (e) {
+      if (this.isNonRetriableError(e))
+        throw e;
+      return 0;
+    }
   }
 
   async content(): Promise<string> {

tests/page/locator-query.spec.ts

@@ -272,3 +272,10 @@ it('alias methods coverage', async ({ page }) => {
   await expect(page.locator('div').getByRole('button')).toHaveCount(1);
   await expect(page.mainFrame().locator('button')).toHaveCount(1);
 });
+
+it('count() should not throw during navigation', async ({ page }) => {
+  await page.setContent(`<div>A</div>`);
+  const __testHookBeforeQuery = () => page.goto('data:text/html,<div>A</div><div>B</div>');
+  // @ts-expect-error
+  expect(await page.locator('div').count({ __testHookBeforeQuery })).toBe(0);
+});

utils/doclint/missingDocs.js

@@ -42,7 +42,7 @@ module.exports = function lint(documentation, jsSources, apiFileName) {
       }
       for (const paramName of params) {
         const found = members.some(member => paramsForMember(member).has(paramName));
-        if (!found)
+        if (!found && !paramName.startsWith('_'))
           errors.push(`Missing documentation for "${className}.${methodName}.${paramName}"`);
       }
     }