Migrate most mustachio tests to null safety

test/mustachio/aot_compiler_builder_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-// @dart=2.9
-
 @Timeout.factor(4)
 import 'dart:convert';
 import 'package:analyzer/dart/element/element.dart';
@@ -14,7 +12,7 @@ import 'package:test/test.dart';
 import 'builder_test_base.dart';
 
 void main() {
-  InMemoryAssetWriter writer;
+  late InMemoryAssetWriter writer;
 
   Future<LibraryElement> resolveGeneratedLibrary() async {
     var rendererAsset = AssetId('foo', 'lib/foo.aot_renderers_for_html.dart');
@@ -65,7 +63,7 @@ library foo;
 import 'package:mustachio/annotations.dart';
 ''');
     var rendererAsset = AssetId('foo', 'lib/foo.aot_renderers_for_html.dart');
-    var generatedContent = utf8.decode(writer.assets[rendererAsset]);
+    var generatedContent = utf8.decode(writer.assets[rendererAsset]!);
     expect(
         generatedContent, contains('String renderFoo<T>(_i1.Foo<T> context0)'));
   });
@@ -87,7 +85,7 @@ import 'package:mustachio/annotations.dart';
       },
     );
     var rendererAsset = AssetId('foo', 'lib/foo.aot_renderers_for_html.dart');
-    var generatedContent = utf8.decode(writer.assets[rendererAsset]);
+    var generatedContent = utf8.decode(writer.assets[rendererAsset]!);
     expect(
         generatedContent,
         contains(
@@ -102,9 +100,9 @@ class Baz {}
 ''');
     var renderersLibrary = await resolveGeneratedLibrary();
 
-    var fooRenderFunction = renderersLibrary.getTopLevelFunction('renderFoo');
+    var fooRenderFunction = renderersLibrary.getTopLevelFunction('renderFoo')!;
     expect(fooRenderFunction.typeParameters, hasLength(1));
-    var fBound = fooRenderFunction.typeParameters.single.bound;
+    var fBound = fooRenderFunction.typeParameters.single.bound!;
     expect(fBound.getDisplayString(withNullability: false), equals('num'));
   });
 }

test/mustachio/builder_test_base.dart

@@ -2,11 +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.
 
-// @dart=2.9
-
 import 'package:analyzer/dart/element/element.dart';
 import 'package:build/build.dart';
 import 'package:build_test/build_test.dart';
+import 'package:collection/collection.dart';
 
 import '../../tool/mustachio/builder.dart';
 
@@ -57,7 +56,7 @@ Future<void> testMustachioBuilder(
   InMemoryAssetWriter writer,
   String sourceLibraryContent, {
   String libraryFrontMatter = libraryFrontMatter,
-  Map<String, String> additionalAssets,
+  Map<String, String> additionalAssets = const {},
 }) async {
   sourceLibraryContent = '''
 $libraryFrontMatter
@@ -74,15 +73,16 @@ $sourceLibraryContent
       'foo|lib/templates/md/bar.md': 'EMPTY',
       'foo|lib/templates/html/baz.html': 'EMPTY',
       'foo|lib/templates/md/baz.md': 'EMPTY',
-      ...?additionalAssets,
+      ...additionalAssets,
     },
     writer: writer,
   );
 }
 
 extension LibraryExtensions on LibraryElement {
-  /// Returns the top-level function in [this] library, named [name].
-  FunctionElement getTopLevelFunction(String name) => topLevelElements
+  /// Returns the top-level function in [this] library, named [name], or `null`
+  /// if no function is found.
+  FunctionElement? getTopLevelFunction(String name) => topLevelElements
       .whereType<FunctionElement>()
-      .firstWhere((element) => element.name == name, orElse: () => null);
+      .firstWhereOrNull((element) => element.name == name);
 }

test/mustachio/parser_test.dart

@@ -1,4 +1,6 @@
-// @dart=2.9
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// 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:dartdoc/src/mustachio/parser.dart';
 import 'package:test/test.dart';
@@ -354,11 +356,11 @@ void main() {
     expect(ast, hasLength(2));
     _expectText(ast[0], equals('Text '));
     var section = ast[1] as Section;
-    _expectSection(section, equals(['key']));
+    _expectSection(section, equals(['key']), spanStart: 5, spanEnd: 49);
     expect(section.children, hasLength(3));
     _expectText(section.children[0], equals(' AA '));
     var innerSection = section.children[1] as Section;
-    _expectSection(innerSection, equals(['key']));
+    _expectSection(innerSection, equals(['key']), spanStart: 17, spanEnd: 37);
     expect(innerSection.children, hasLength(1));
     _expectText(innerSection.children[0], equals(' BB '));
   });
@@ -407,7 +409,7 @@ void main() {
 }
 
 void _expectText(MustachioNode node, Object matcher,
-    {int spanStart, int spanEnd}) {
+    {int? spanStart, int? spanEnd}) {
   expect(node, isA<Text>().having((e) => e.content, 'content', matcher));
   if (spanStart != null) {
     expect(
@@ -421,82 +423,94 @@ void _expectText(MustachioNode node, Object matcher,
   }
 }
 
-void _expectVariable(MustachioNode node, Object matcher,
-    {bool escape = true,
-    int spanStart,
-    int spanEnd,
-    int keySpanStart,
-    int keySpanEnd}) {
+void _expectVariable(
+  MustachioNode node,
+  Object matcher, {
+  bool escape = true,
+  required int spanStart,
+  required int spanEnd,
+  int? keySpanStart,
+  int? keySpanEnd,
+}) {
   expect(
       node,
       isA<Variable>()
           .having((e) => e.key, 'key', matcher)
           .having((e) => e.escape, 'escape', escape));
-  if (spanStart != null) {
-    var actualSpanStart = (node as Variable).span.start.offset;
-    _expectSpanOffset('Variable', 'start', actualSpanStart, spanStart);
-  }
-  if (spanEnd != null) {
-    var actualSpanEnd = (node as Variable).span.end.offset;
-    _expectSpanOffset('Variable', 'end', actualSpanEnd, spanEnd);
-  }
+  node as Variable;
+
+  var actualSpanStart = node.span.start.offset;
+  _expectSpanOffset('Variable', 'start', actualSpanStart, spanStart);
+
+  var actualSpanEnd = node.span.end.offset;
+  _expectSpanOffset('Variable', 'end', actualSpanEnd, spanEnd);
+
   if (keySpanStart != null) {
-    var actualKeySpanStart = (node as Variable).keySpan.start.offset;
+    var actualKeySpanStart = node.keySpan.start.offset;
     _expectSpanOffset(
         'Variable key', 'start', actualKeySpanStart, keySpanStart);
   }
   if (keySpanEnd != null) {
-    var actualKeySpanEnd = (node as Variable).keySpan.end.offset;
+    var actualKeySpanEnd = node.keySpan.end.offset;
     _expectSpanOffset('Variable key', 'end', actualKeySpanEnd, keySpanEnd);
   }
 }
 
-void _expectSection(MustachioNode node, Object matcher,
-    {bool invert = false,
-    int spanStart,
-    int spanEnd,
-    int keySpanStart,
-    int keySpanEnd}) {
+void _expectSection(
+  MustachioNode node,
+  Object matcher, {
+  bool invert = false,
+  required int spanStart,
+  required int spanEnd,
+  int? keySpanStart,
+  int? keySpanEnd,
+}) {
   expect(
       node,
       isA<Section>()
           .having((e) => e.key, 'key', matcher)
           .having((e) => e.invert, 'invert', invert));
-  if (spanStart != null) {
-    var actualSpanStart = (node as Section).span.start.offset;
-    _expectSpanOffset('Section', 'start', actualSpanStart, spanStart);
-  }
-  if (spanEnd != null) {
-    var actualSpanEnd = (node as Section).span.end.offset;
-    _expectSpanOffset('Section', 'end', actualSpanEnd, spanEnd);
-  }
+  node as Section;
+
+  var actualSpanStart = node.span.start.offset;
+  _expectSpanOffset('Section', 'start', actualSpanStart, spanStart);
+
+  var actualSpanEnd = node.span.end.offset;
+  _expectSpanOffset('Section', 'end', actualSpanEnd, spanEnd);
+
   if (keySpanStart != null) {
-    var actualKeySpanStart = (node as Section).keySpan.start.offset;
+    var actualKeySpanStart = node.keySpan.start.offset;
     _expectSpanOffset('Section key', 'start', actualKeySpanStart, keySpanStart);
   }
   if (keySpanEnd != null) {
-    var actualKeySpanEnd = (node as Section).keySpan.end.offset;
+    var actualKeySpanEnd = node.keySpan.end.offset;
     _expectSpanOffset('Section key', 'end', actualKeySpanEnd, keySpanEnd);
   }
 }
 
-void _expectPartial(MustachioNode node, Object matcher,
-    {int spanStart, int spanEnd, int keySpanStart, int keySpanEnd}) {
+void _expectPartial(
+  MustachioNode node,
+  Object matcher, {
+  required int spanStart,
+  required int spanEnd,
+  int? keySpanStart,
+  int? keySpanEnd,
+}) {
   expect(node, isA<Partial>().having((e) => e.key, 'key', matcher));
-  if (spanStart != null) {
-    var actualSpanStart = (node as Partial).span.start.offset;
-    _expectSpanOffset('Partial', 'start', actualSpanStart, spanStart);
-  }
-  if (spanEnd != null) {
-    var actualSpanEnd = (node as Partial).span.end.offset;
-    _expectSpanOffset('Partial', 'end', actualSpanEnd, spanEnd);
-  }
+  node as Partial;
+
+  var actualSpanStart = node.span.start.offset;
+  _expectSpanOffset('Partial', 'start', actualSpanStart, spanStart);
+
+  var actualSpanEnd = node.span.end.offset;
+  _expectSpanOffset('Partial', 'end', actualSpanEnd, spanEnd);
+
   if (keySpanStart != null) {
-    var actualKeySpanStart = (node as Partial).keySpan.start.offset;
+    var actualKeySpanStart = node.keySpan.start.offset;
     _expectSpanOffset('Partial key', 'start', actualKeySpanStart, keySpanStart);
   }
   if (keySpanEnd != null) {
-    var actualKeySpanEnd = (node as Partial).keySpan.end.offset;
+    var actualKeySpanEnd = node.keySpan.end.offset;
     _expectSpanOffset('Partial key', 'end', actualKeySpanEnd, keySpanEnd);
   }
 }

test/mustachio/render_tests_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-// @dart=2.9
-
 import 'dart:io';
 import 'dart:isolate' show Isolate;
 
@@ -17,7 +15,7 @@ void main() {
     var testCasePattern = RegExp(r'test\(.*,');
     var dartdocLibUri = await Isolate.resolvePackageUri(
         Uri.parse('package:dartdoc/dartdoc.dart'));
-    var dartdocPath = p.dirname(p.dirname(dartdocLibUri.path));
+    var dartdocPath = p.dirname(p.dirname(dartdocLibUri!.path));
     // Correct Windows issue path coming out of [Isolate.resolvePackageUri].
     if (p.separator == p.windows.separator && dartdocPath.startsWith('/')) {
       dartdocPath = dartdocPath.substring(1).replaceAll('/', p.separator);
@@ -35,15 +33,15 @@ void main() {
         .where((line) => !line.contains('Parser '))
         // Ignore tests about the SimpleRenderer.
         .where((line) => !line.contains('SimpleRenderer'))
-        .map((line) => testCasePattern.firstMatch(line).group(0))
+        .map((line) => testCasePattern.firstMatch(line)!.group(0))
         .toSet();
 
     var aotCompilerRenderTest = File(p.join(
             dartdocPath, 'test', 'mustachio', 'aot_compiler_render_test.dart'))
         .readAsLinesSync();
     var aotCompilerTestCases = aotCompilerRenderTest
         .where((line) => testCasePattern.hasMatch(line))
-        .map((line) => testCasePattern.firstMatch(line).group(0))
+        .map((line) => testCasePattern.firstMatch(line)!.group(0))
         .toSet();
 
     var difference = runtimeRendererTestCases.difference(aotCompilerTestCases);

test/mustachio/runtime_renderer_builder_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-// @dart=2.9
-
 @Timeout.factor(2)
 import 'dart:convert';
 import 'package:analyzer/dart/element/element.dart';
@@ -14,7 +12,7 @@ import 'package:test/test.dart';
 import 'builder_test_base.dart';
 
 void main() {
-  InMemoryAssetWriter writer;
+  late InMemoryAssetWriter writer;
 
   Future<LibraryElement> resolveGeneratedLibrary() async {
     var rendererAsset = AssetId('foo', 'lib/foo.runtime_renderers.dart');
@@ -29,8 +27,8 @@ void main() {
   });
 
   group('builds a renderer class', () {
-    LibraryElement renderersLibrary;
-    String generatedContent;
+    late final LibraryElement renderersLibrary;
+    late final String generatedContent;
 
     // Builders are fairly expensive (about 4 seconds per `testBuilder` call),
     // so this [setUpAll] saves significant time over [setUp].
@@ -56,7 +54,7 @@ class Baz {}
 ''');
       renderersLibrary = await resolveGeneratedLibrary();
       var rendererAsset = AssetId('foo', 'lib/foo.runtime_renderers.dart');
-      generatedContent = utf8.decode(writer.assets[rendererAsset]);
+      generatedContent = utf8.decode(writer.assets[rendererAsset]!);
     });
 
     test('for a class which implicitly extends Object', () {
@@ -179,7 +177,7 @@ import 'package:mustachio/annotations.dart';
   });
 
   group('builds a renderer class for a generic type', () {
-    String generatedContent;
+    late final String generatedContent;
 
     // Builders are fairly expensive (about 4 seconds per `testBuilder` call),
     // so this [setUpAll] saves significant time over [setUp].
@@ -198,7 +196,7 @@ library foo;
 import 'package:mustachio/annotations.dart';
 ''');
       var rendererAsset = AssetId('foo', 'lib/foo.runtime_renderers.dart');
-      generatedContent = utf8.decode(writer.assets[rendererAsset]);
+      generatedContent = utf8.decode(writer.assets[rendererAsset]!);
     });
 
     test('with a corresponding public API function', () async {
@@ -241,19 +239,19 @@ class Baz {}
 ''');
     var renderersLibrary = await resolveGeneratedLibrary();
 
-    var fooRenderFunction = renderersLibrary.getTopLevelFunction('renderFoo');
+    var fooRenderFunction = renderersLibrary.getTopLevelFunction('renderFoo')!;
     expect(fooRenderFunction.typeParameters, hasLength(1));
-    var fBound = fooRenderFunction.typeParameters.single.bound;
+    var fBound = fooRenderFunction.typeParameters.single.bound!;
     expect(fBound.getDisplayString(withNullability: false), equals('num'));
 
-    var fooRendererClass = renderersLibrary.getType('_Renderer_Foo');
+    var fooRendererClass = renderersLibrary.getType('_Renderer_Foo')!;
     expect(fooRendererClass.typeParameters, hasLength(1));
-    var cBound = fooRenderFunction.typeParameters.single.bound;
+    var cBound = fooRenderFunction.typeParameters.single.bound!;
     expect(cBound.getDisplayString(withNullability: false), equals('num'));
   });
 
   group('does not generate a renderer', () {
-    LibraryElement renderersLibrary;
+    late final LibraryElement renderersLibrary;
 
     setUpAll(() async {
       writer = InMemoryAssetWriter();