core(driver): wait for Page.frameNavigated for about:blank

lighthouse-core/gather/driver.js

@@ -496,6 +496,16 @@ class Driver {
     });
   }
 
+  /**
+   * Returns a promise that resolve when a frame has been navigated.
+   * Used for detecting that our about:blank reset has been completed.
+   */
+  _waitForFrameNavigated() {
+    return new Promise(resolve => {
+      this.once('Page.frameNavigated', resolve);
+    });
+  }
+
   /**
    * Returns a promise that resolves when the network has been idle (after DCL) for
    * `networkQuietThresholdMs` ms and a method to cancel internal network listeners/timeout.
@@ -824,10 +834,11 @@ class Driver {
    * possible workaround.
    * Resolves on the url of the loaded page, taking into account any redirects.
    * @param {string} url
-   * @param {{waitForLoad?: boolean, passContext?: LH.Gatherer.PassContext}} options
+   * @param {{waitForLoad?: boolean, waitForNavigated?: boolean, passContext?: LH.Gatherer.PassContext}} options
    * @return {Promise<string>}
    */
   async gotoURL(url, options = {}) {
+    const waitForNavigated = options.waitForNavigated || false;
     const waitForLoad = options.waitForLoad || false;
     const passContext = /** @type {Partial<LH.Gatherer.PassContext>} */ (options.passContext || {});
     const disableJS = passContext.disableJavaScript || false;
@@ -843,6 +854,10 @@ class Driver {
     this.setNextProtocolTimeout(30 * 1000);
     this.sendCommand('Page.navigate', {url});
 
+    if (waitForNavigated) {
+      await this._waitForFrameNavigated();
+    }
+
     if (waitForLoad) {
       const passConfig = /** @type {Partial<LH.Config.Pass>} */ (passContext.passConfig || {});
       let {pauseAfterLoadMs, networkQuietThresholdMs, cpuQuietThresholdMs} = passConfig;

lighthouse-core/gather/gather-runner.js

@@ -68,18 +68,15 @@ class GatherRunner {
    * never fired on it.
    * @param {Driver} driver
    * @param {string=} url
-   * @param {number=} duration
    * @return {Promise<void>}
    */
   static async loadBlank(
       driver,
-      url = constants.defaultPassConfig.blankPage,
-      duration = constants.defaultPassConfig.blankDuration
+      url = constants.defaultPassConfig.blankPage
   ) {
     const status = {msg: 'Resetting state with about:blank', id: 'lh:gather:loadBlank'};
     log.time(status);
-    await driver.gotoURL(url);
-    await new Promise(resolve => setTimeout(resolve, duration));
+    await driver.gotoURL(url, {waitForNavigated: true});
     log.timeEnd(status);
   }
 
@@ -458,7 +455,7 @@ class GatherRunner {
         await driver.setThrottling(options.settings, passConfig);
         if (!isFirstPass) {
           // Already on blank page if driver was just set up.
-          await GatherRunner.loadBlank(driver, passConfig.blankPage, passConfig.blankDuration);
+          await GatherRunner.loadBlank(driver, passConfig.blankPage);
         }
         await GatherRunner.beforePass(passContext, gathererResults);
         await GatherRunner.pass(passContext, gathererResults);