Fix for extra diagnostics when now all files created at the start.

Change-Id: Icda792b55a1381294c4e3490694fb99ee2c4ca3f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302446
Commit-Queue: Konstantin Shcheglov <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>

Author: scheglov

pkg/analysis_server/test/client/completion_driver_test.dart

@@ -72,10 +72,15 @@ abstract class AbstractCompletionDriverTest
   Future<List<CompletionSuggestion>> addTestFile(String content,
       {int? offset}) async {
     driver.addTestFile(content, offset: offset);
-    await getSuggestions();
+
+    // Wait after adding the test file, this might affect diagnostics.
+    await pumpEventQueue(times: 1000);
+
     // For sanity, ensure that there are no errors recorded for project files
     // since that may lead to unexpected results.
     _assertNoErrorsInProjectFiles();
+
+    await getSuggestions();
     return suggestions;
   }