diff --git a/pkg/analyzer/test/src/dart/resolution/language_version_test.dart b/pkg/analyzer/test/src/dart/resolution/language_version_test.dart
index 2391856395d..d200a01b6e6 100644
--- a/pkg/analyzer/test/src/dart/resolution/language_version_test.dart
+++ b/pkg/analyzer/test/src/dart/resolution/language_version_test.dart
@@ -2,16 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/src/context/packages.dart';
 import 'package:analyzer/src/dart/error/syntactic_errors.dart';
 import 'package:analyzer/src/error/codes.dart';
-import 'package:analyzer/src/test_utilities/find_element.dart';
-import 'package:analyzer/src/test_utilities/find_node.dart';
 import 'package:analyzer/src/test_utilities/mock_sdk.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
-import 'driver_resolution.dart';
-import 'with_null_safety_mixin.dart';
+import 'context_collection_resolution.dart';
 
 main() {
   defineReflectiveSuite(() {
@@ -37,14 +33,14 @@ class NullSafetyExperimentGlobalTest extends _FeaturesTest
     },
     {
       "name": "aaa",
-      "rootUri": "${toUriStr('/aaa')}",
+      "rootUri": "${toUriStr('$workspaceRootPath/aaa')}",
       "packageUri": "lib/"
     }
   ]
 }
 ''');
 
-    newFile('/aaa/lib/a.dart', content: r'''
+    newFile('$workspaceRootPath/aaa/lib/a.dart', content: r'''
 int a = 0;
 ''');
 
@@ -73,7 +69,7 @@ var z = pi;
     },
     {
       "name": "aaa",
-      "rootUri": "${toUriStr('/aaa')}",
+      "rootUri": "${toUriStr('$workspaceRootPath/aaa')}",
       "packageUri": "lib/",
       "languageVersion": "2.7"
     }
@@ -81,7 +77,7 @@ var z = pi;
 }
 ''');
 
-    newFile('/aaa/lib/a.dart', content: r'''
+    newFile('$workspaceRootPath/aaa/lib/a.dart', content: r'''
 int a = 0;
 ''');
 
@@ -124,16 +120,17 @@ class NullSafetyUsingAllowedExperimentsTest extends _FeaturesTest {
 }
 ''');
 
-    var path = convertPath('/test/bin/a.dart');
-    await _resolveFile(path, r'''
+    var path = '$testPackageRootPath/bin/a.dart';
+
+    await resolveFileCode(path, r'''
 var x = 0;
 ''');
-    assertErrorsInList(result.errors, []);
+    assertErrorsInResult([]);
     assertType(findElement.topVar('x').type, 'int*');
 
-    // Upgrade the language version to `2.10`, so enabled Null Safety.
-    driver.changeFile(path);
-    await _resolveFile(path, r'''
+    // Upgrade the language version to `2.10`, so enable Null Safety.
+    _changeFile(path);
+    await resolveFileCode(path, r'''
 // @dart = 2.10
 var x = 0;
 ''');
@@ -157,13 +154,16 @@ var x = 0;
 }
 ''');
 
-    await assertNoErrorsInCode('''
+    var path = testFilePath;
+
+    await resolveFileCode(path, '''
 var x = 0;
 ''');
+    assertErrorsInResult([]);
     assertType(findElement.topVar('x').type, 'int*');
 
-    // Upgrade the language version to `2.10`, so enabled Null Safety.
-    _changeTestFile();
+    // Upgrade the language version to `2.10`, so enable Null Safety.
+    _changeFile(path);
     await assertNoErrorsInCode('''
 // @dart = 2.10
 var x = 0;
@@ -187,16 +187,17 @@ var x = 0;
 }
 ''');
 
-    var path = convertPath('/test/bin/a.dart');
-    await _resolveFile(path, r'''
+    var path = '$testPackageRootPath/bin/a.dart';
+
+    await resolveFileCode(path, r'''
 var x = 0;
 ''');
     assertErrorsInList(result.errors, []);
     assertType(findElement.topVar('x').type, 'int');
 
     // Downgrade the version to `2.8`, so disable Null Safety.
-    driver.changeFile(path);
-    await _resolveFile(path, r'''
+    _changeFile(path);
+    await resolveFileCode(path, r'''
 // @dart = 2.8
 var x = 0;
 ''');
@@ -219,13 +220,16 @@ var x = 0;
 }
 ''');
 
-    await assertNoErrorsInCode('''
+    var path = testFilePath;
+
+    await resolveFileCode(path, '''
 var x = 0;
 ''');
+    assertErrorsInResult([]);
     assertType(findElement.topVar('x').type, 'int');
 
     // Downgrade the version to `2.8`, so disable Null Safety.
-    _changeTestFile();
+    _changeFile(path);
     await assertNoErrorsInCode('''
 // @dart = 2.8
 var x = 0;
@@ -233,11 +237,6 @@ var x = 0;
     assertType(findElement.topVar('x').type, 'int*');
   }
 
-  void _changeTestFile() {
-    var path = convertPath('/test/lib/test.dart');
-    driver.changeFile(path);
-  }
-
   void _configureAllowedExperimentsTestNullSafety() {
     _newSdkExperimentsFile(r'''
 {
@@ -265,14 +264,6 @@ var x = 0;
       content: content,
     );
   }
-
-  Future<void> _resolveFile(String path, String content) async {
-    newFile(path, content: content);
-    result = await resolveFile(path);
-
-    findNode = FindNode(result.content, result.unit);
-    findElement = FindElement(result.unit);
-  }
 }
 
 @reflectiveTest
@@ -324,15 +315,20 @@ extension E on int {}
   }
 }
 
-class _FeaturesTest extends DriverResolutionTest {
-  void _configureTestWithJsonConfig(String content) {
-    newFile('/test/.dart_tool/package_config.json', content: content);
+class _FeaturesTest extends PubPackageResolutionTest {
+  /// Do necessary work to ensure that the file with the [path] is considered
+  /// changed for the purpose of following analysis.
+  ///
+  /// Currently we just dispose the whole analysis context collection, so when
+  /// we ask to analyze anything again, we will pick up the new file content.
+  void _changeFile(String path) {
+    disposeAnalysisContextCollection();
+  }
 
-    driver.configure(
-      packages: findPackagesFrom(
-        resourceProvider,
-        getFolder('/test'),
-      ),
+  void _configureTestWithJsonConfig(String content) {
+    newFile(
+      '$testPackageRootPath/.dart_tool/package_config.json',
+      content: content,
     );
   }
 }
diff --git a/pkg/analyzer/test/src/diagnostics/subtype_of_sealed_class_test.dart b/pkg/analyzer/test/src/diagnostics/subtype_of_sealed_class_test.dart
index 1ac4382093f..2f784fbe4e0 100644
--- a/pkg/analyzer/test/src/diagnostics/subtype_of_sealed_class_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/subtype_of_sealed_class_test.dart
@@ -2,13 +2,10 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/error/codes.dart';
-import 'package:analyzer/src/test_utilities/package_mixin.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
-import '../../generated/test_support.dart';
-import '../dart/resolution/driver_resolution.dart';
+import '../dart/resolution/context_collection_resolution.dart';
 
 main() {
   defineReflectiveSuite(() {
@@ -17,116 +14,125 @@ main() {
 }
 
 @reflectiveTest
-class SubtypeOfSealedClassTest extends DriverResolutionTest with PackageMixin {
+class SubtypeOfSealedClassTest extends PubPackageResolutionTest {
+  @override
+  void setUp() {
+    super.setUp();
+    writeTestPackageConfigWithMeta();
+  }
+
   test_extendingSealedClass() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    await newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 class Bar extends Foo {}
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 31, 24),
     ]);
   }
 
   test_implementingSealedClass() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 class Bar implements Foo {}
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 31, 27),
     ]);
   }
 
   test_mixinApplicationOfSealedClass() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 class Bar1 {}
 class Bar2 = Bar1 with Foo;
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 45, 27),
     ]);
   }
 
   test_mixinApplicationOfSealedMixin() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed mixin Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 class Bar1 {}
 class Bar2 = Bar1 with Foo;
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 45, 27),
     ]);
   }
 
   test_mixingInWithSealedMixin() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed mixin Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 class Bar extends Object with Foo {}
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 31, 36),
     ]);
   }
 
   test_mixinImplementsSealedClass() async {
-    addMetaPackage();
-    _addPackage('foo', r'''
+    writeTestPackageConfigWith({
+      'foo': '$workspaceRootPath/foo',
+    }, meta: true);
+
+    newFile('$workspaceRootPath/foo/lib/foo.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertErrorsInCode(r'''
 import 'package:foo/foo.dart';
 mixin Bar implements Foo {}
-''');
-    await _resolveFile('/pkg1/lib/lib1.dart', [
+''', [
       error(HintCode.SUBTYPE_OF_SEALED_CLASS, 31, 27),
     ]);
   }
 
   test_withinLibrary_OK() async {
-    addMetaPackage();
-
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await assertNoErrorsInCode(r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 
@@ -135,88 +141,63 @@ class Bar2 implements Foo {}
 class Bar4 = Bar1 with Foo;
 mixin Bar5 implements Foo {}
 ''');
-    await _resolveFile('/pkg1/lib/lib1.dart');
   }
 
   test_withinPackageLibDirectory_OK() async {
-    addMetaPackage();
-
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await newFile('$testPackageLibPath/a.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
-    newFile('/pkg1/lib/src/lib2.dart', content: r'''
-import '../lib1.dart';
+
+    await resolveFileCode('$testPackageLibPath/src/b.dart', r'''
+import '../a.dart';
 class Bar1 extends Foo {}
 class Bar2 implements Foo {}
 class Bar4 = Bar1 with Foo;
 mixin Bar5 implements Foo {}
 ''');
-    await _resolveFile('/pkg1/lib/lib1.dart');
-    await _resolveFile('/pkg1/lib/src/lib2.dart');
+    assertNoErrorsInResult();
   }
 
   test_withinPackageTestDirectory_OK() async {
-    addMetaPackage();
-
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    await newFile('$testPackageLibPath/a.dart', content: r'''
 import 'package:meta/meta.dart';
 @sealed class Foo {}
 ''');
-    newFile('/pkg1/test/test.dart', content: r'''
-import '../lib/lib1.dart';
+
+    await resolveFileCode('$testPackageRootPath/test/test.dart', r'''
+import 'package:test/a.dart';
+
 class Bar1 extends Foo {}
 class Bar2 implements Foo {}
 class Bar4 = Bar1 with Foo;
 mixin Bar5 implements Foo {}
 ''');
-    await _resolveFile('/pkg1/lib/lib1.dart');
-    await _resolveFile('/pkg1/test/test.dart');
+    assertNoErrorsInResult();
   }
 
   test_withinPart_OK() async {
-    addMetaPackage();
+    var libPath = '$testPackageLibPath/a.dart';
+    var partPath = '$testPackageLibPath/b.dart';
 
-    _newPubPackageRoot('/pkg1');
-    newFile('/pkg1/lib/lib1.dart', content: r'''
+    newFile(libPath, content: r'''
 import 'package:meta/meta.dart';
-part 'part1.dart';
+part 'b.dart';
 @sealed class Foo {}
 ''');
-    newFile('/pkg1/lib/part1.dart', content: r'''
-part of 'lib1.dart';
+
+    await newFile(partPath, content: r'''
+part of 'a.dart';
 class Bar1 extends Foo {}
 class Bar2 implements Foo {}
 class Bar4 = Bar1 with Foo;
 mixin Bar5 implements Foo {}
 ''');
-    await _resolveFile('/pkg1/lib/lib1.dart');
-  }
 
-  /// Add a package named [name], and one library file, with content
-  /// [libraryContent].
-  void _addPackage(String name, String libraryContent) {
-    Folder lib = addPubPackage(name);
-    newFile(join(lib.path, '$name.dart'), content: libraryContent);
-  }
+    await resolveFile2(libPath);
+    assertNoErrorsInResult();
 
-  /// Write a pubspec file at [root], so that BestPracticesVerifier can see
-  /// that [root] is the root of a PubWorkspace, and a PubWorkspacePackage.
-  void _newPubPackageRoot(String root) {
-    newFile('$root/pubspec.yaml');
-    configureWorkspace(root: root);
-  }
-
-  /// Resolve the file with the given [path].
-  ///
-  /// Similar to ResolutionTest.resolveTestFile, but a custom path is supported.
-  Future<void> _resolveFile(
-    String path, [
-    List<ExpectedError> expectedErrors = const [],
-  ]) async {
-    result = await resolveFile(convertPath(path));
-    assertErrorsInResolvedUnit(result, expectedErrors);
+    await resolveFile2(partPath);
+    assertNoErrorsInResult();
   }
 }