Issue #3375584 by znerol, longwave, Spokje: [random test failure] Random...

Issue #3375584 by znerol, longwave, Spokje: [random test failure] Random failure in PathWorkspacesTest

core/modules/workspaces/tests/src/Functional/PathWorkspacesTest.php

@@ -106,6 +106,11 @@ public function testPathAliases() {
     // Publish the workspace and check that the alias can be accessed in Live.
     $stage->publish();
     $this->assertAccessiblePaths([$path]);
+
+    // The \Drupal\path_alias\AliasWhitelist service performs cache clears after
+    // Drupal has flushed the response to the client; wait for this to finish.
+    sleep(1);
+
     $this->assertNotEmpty(\Drupal::cache('data')->get('preload-paths:/node/1'));
   }
 
@@ -147,8 +152,14 @@ public function testPathAliasesUserSwitch() {
     // Publish the workspace and check that the alias can be accessed in Live.
     $this->drupalLogin($this->rootUser);
     $stage->publish();
+
     $this->drupalLogout();
     $this->assertAccessiblePaths([$path]);
+
+    // The \Drupal\path_alias\AliasWhitelist service performs cache clears after
+    // Drupal has flushed the response to the client; wait for this to finish.
+    sleep(1);
+
     $this->assertNotEmpty(\Drupal::cache('data')->get('preload-paths:/node/1'));
   }