Fix updated underscore lint (#1701)

diff --git a/pkgs/test/CHANGELOG.md b/pkgs/test/CHANGELOG.md
index 5c15d42..23a8c0d 100644
--- a/pkgs/test/CHANGELOG.md
+++ b/pkgs/test/CHANGELOG.md
@@ -1,3 +1,5 @@
+## 1.21.2-dev
+
 ## 1.21.1
 
 * Fix a bug loading JS sources with non-utf8 content while parsing coverage
diff --git a/pkgs/test/pubspec.yaml b/pkgs/test/pubspec.yaml
index 42053e8..abd1091 100644
--- a/pkgs/test/pubspec.yaml
+++ b/pkgs/test/pubspec.yaml
@@ -1,5 +1,5 @@
 name: test
-version: 1.21.1
+version: 1.21.2-dev
 description: >-
   A full featured library for writing and running Dart tests across platforms.
 repository: https://github.com/dart-lang/test/tree/master/pkgs/test
diff --git a/pkgs/test/test/runner/coverage_test.dart b/pkgs/test/test/runner/coverage_test.dart
index 26eea45..829e281 100644
--- a/pkgs/test/test/runner/coverage_test.dart
+++ b/pkgs/test/test/runner/coverage_test.dart
@@ -7,10 +7,9 @@
 import 'dart:convert';
 import 'dart:io';
 
-import 'package:test_descriptor/test_descriptor.dart' as d;
-
 import 'package:path/path.dart' as p;
 import 'package:test/test.dart';
+import 'package:test_descriptor/test_descriptor.dart' as d;
 import 'package:test_process/test_process.dart';
 
 import '../io.dart';
@@ -21,8 +20,7 @@
   group('with the --coverage flag,', () {
     late Directory coverageDirectory;
 
-    Future<void> _validateCoverage(
-        TestProcess test, String coveragePath) async {
+    Future<void> validateCoverage(TestProcess test, String coveragePath) async {
       expect(test.stdout, emitsThrough(contains('+1: All tests passed!')));
       await test.shouldExit(0);
 
@@ -54,13 +52,13 @@
     test('gathers coverage for VM tests', () async {
       var test =
           await runTest(['--coverage', coverageDirectory.path, 'test.dart']);
-      await _validateCoverage(test, 'test.dart.vm.json');
+      await validateCoverage(test, 'test.dart.vm.json');
     });
 
     test('gathers coverage for Chrome tests', () async {
       var test = await runTest(
           ['--coverage', coverageDirectory.path, 'test.dart', '-p', 'chrome']);
-      await _validateCoverage(test, 'test.dart.chrome.json');
+      await validateCoverage(test, 'test.dart.chrome.json');
     });
 
     test(
@@ -125,7 +123,7 @@
         '-p',
         'chrome'
       ]);
-      await _validateCoverage(test, 'js_with_unicode_test.dart.chrome.json');
+      await validateCoverage(test, 'js_with_unicode_test.dart.chrome.json');
     });
   });
 }
diff --git a/pkgs/test/test/util/one_off_handler_test.dart b/pkgs/test/test/util/one_off_handler_test.dart
index c18f2da..c10a7af 100644
--- a/pkgs/test/test/util/one_off_handler_test.dart
+++ b/pkgs/test/test/util/one_off_handler_test.dart
@@ -12,17 +12,17 @@
   late OneOffHandler handler;
   setUp(() => handler = OneOffHandler());
 
-  Future<shelf.Response> _handle(shelf.Request request) =>
+  Future<shelf.Response> handle(shelf.Request request) =>
       Future.sync(() => handler.handler(request));
 
   test('returns a 404 for a root URL', () async {
     var request = shelf.Request('GET', Uri.parse('http://localhost/'));
-    expect((await _handle(request)).statusCode, equals(404));
+    expect((await handle(request)).statusCode, equals(404));
   });
 
   test('returns a 404 for an unhandled URL', () async {
     var request = shelf.Request('GET', Uri.parse('http://localhost/1'));
-    expect((await _handle(request)).statusCode, equals(404));
+    expect((await handle(request)).statusCode, equals(404));
   });
 
   test('passes a request to a handler only once', () async {
@@ -32,12 +32,12 @@
     }));
 
     var request = shelf.Request('GET', Uri.parse('http://localhost/$path'));
-    var response = await _handle(request);
+    var response = await handle(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('good job!')));
 
     request = shelf.Request('GET', Uri.parse('http://localhost/$path'));
-    expect((await _handle(request)).statusCode, equals(404));
+    expect((await handle(request)).statusCode, equals(404));
   });
 
   test('passes requests to the correct handlers', () async {
@@ -57,17 +57,17 @@
     }));
 
     var request = shelf.Request('GET', Uri.parse('http://localhost/$path2'));
-    var response = await _handle(request);
+    var response = await handle(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('two')));
 
     request = shelf.Request('GET', Uri.parse('http://localhost/$path1'));
-    response = await _handle(request);
+    response = await handle(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('one')));
 
     request = shelf.Request('GET', Uri.parse('http://localhost/$path3'));
-    response = await _handle(request);
+    response = await handle(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('three')));
   });
diff --git a/pkgs/test/test/util/path_handler_test.dart b/pkgs/test/test/util/path_handler_test.dart
index 24daa38..9a5d98b 100644
--- a/pkgs/test/test/util/path_handler_test.dart
+++ b/pkgs/test/test/util/path_handler_test.dart
@@ -12,17 +12,17 @@
   late PathHandler handler;
   setUp(() => handler = PathHandler());
 
-  Future<shelf.Response> _handle(shelf.Request request) =>
+  Future<shelf.Response> localHandler(shelf.Request request) =>
       Future.sync(() => handler.handler(request));
 
   test('returns a 404 for a root URL', () async {
     var request = shelf.Request('GET', Uri.parse('http://localhost/'));
-    expect((await _handle(request)).statusCode, equals(404));
+    expect((await localHandler(request)).statusCode, equals(404));
   });
 
   test('returns a 404 for an unregistered URL', () async {
     var request = shelf.Request('GET', Uri.parse('http://localhost/foo'));
-    expect((await _handle(request)).statusCode, equals(404));
+    expect((await localHandler(request)).statusCode, equals(404));
   });
 
   test('runs a handler for an exact URL', () async {
@@ -33,7 +33,7 @@
       return shelf.Response.ok('good job!');
     }));
 
-    var response = await _handle(request);
+    var response = await localHandler(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('good job!')));
   });
@@ -46,7 +46,7 @@
       return shelf.Response.ok('good job!');
     }));
 
-    var response = await _handle(request);
+    var response = await localHandler(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('good job!')));
   });
@@ -71,7 +71,7 @@
           return shelf.Response.notFound('fake');
         }, count: 0));
 
-    var response = await _handle(request);
+    var response = await localHandler(request);
     expect(response.statusCode, equals(200));
     expect(response.readAsString(), completion(equals('good job!')));
   });
diff --git a/pkgs/test_api/lib/src/backend/metadata.dart b/pkgs/test_api/lib/src/backend/metadata.dart
index 6c459e2..2f94322 100644
--- a/pkgs/test_api/lib/src/backend/metadata.dart
+++ b/pkgs/test_api/lib/src/backend/metadata.dart
@@ -154,7 +154,7 @@
       Map<BooleanSelector, Metadata>? forTag,
       String? languageVersionComment}) {
     // Returns metadata without forTag resolved at all.
-    Metadata _unresolved() => Metadata._(
+    Metadata unresolved() => Metadata._(
         testOn: testOn,
         timeout: timeout,
         skip: skip,
@@ -169,7 +169,7 @@
 
     // If there's no tag-specific metadata, or if none of it applies, just
     // return the metadata as-is.
-    if (forTag == null || tags == null) return _unresolved();
+    if (forTag == null || tags == null) return unresolved();
     tags = Set.from(tags);
     forTag = Map.from(forTag);
 
@@ -182,8 +182,8 @@
       return merged.merge(forTag!.remove(selector)!);
     });
 
-    if (merged == empty) return _unresolved();
-    return merged.merge(_unresolved());
+    if (merged == empty) return unresolved();
+    return merged.merge(unresolved());
   }
 
   /// Creates new Metadata.