Migrated to null-safety.

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.2.0-nullsafety
+
+Migrated to null-safety. 
+
 ## 0.1.6
 
 Renamed classes `LibDir` and `PackageDir` to `LibDir` and `PackageDir`.

example/researcher/pubspec.yaml

@@ -1,16 +1,22 @@
 name: researcher
-description:
-  Example demonstrating how to use the library merging_builder.
+description: Example demonstrating how to use the library merging_builder.
 
 environment:
-  sdk: '>=2.8.1 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 
-dependencies:
+dependencies: null
 
 dev_dependencies:
-  build_runner: ^1.10.0
-  build_test: ^1.2.0
   researcher_builder:
     path: ../researcher_builder
-  source_gen: ^0.9.6
-  test: ^1.15.2
+  build_runner: ^1.12.2
+  build_test: ^2.0.0
+  source_gen: ^0.9.10+4
+  test: ^1.16.8
+
+dependency_overrides:
+  source_gen:
+    git:
+      url: [email protected]:dart-lang/source_gen.git
+      ref: master
+      path: source_gen

example/researcher/test/merging_generator_test.dart

@@ -16,11 +16,19 @@ import 'src/mock_builders/mock_merging_builder.dart';
 /// Note: The path to the input files is specified relative to the main
 /// directory of [merging_builder].
 Future<void> main() async {
-  final libA = LibraryReader(await resolveSource(researcher_a_dot_dart,
-      (resolver) => resolver.findLibraryByName('researcher_a')));
+  final libA = LibraryReader(
+    await resolveSource(
+        researcher_a_dot_dart,
+        (resolver) async =>
+            (await resolver.findLibraryByName('researcher_a'))!),
+  );
 
-  final libB = LibraryReader(await resolveSource(researcher_b_dot_dart,
-      (resolver) => resolver.findLibraryByName('researcher_b')));
+  final libB = LibraryReader(
+    await resolveSource(
+        researcher_b_dot_dart,
+        (resolver) async =>
+            (await resolver.findLibraryByName('researcher_b'))!),
+  );
 
   final numBuilder = MockMergingBuilder<num>(
     generator: AddNumbersGenerator(),

example/researcher/test/src/mock_builders/mock_merging_builder.dart

@@ -1,17 +1,28 @@
+import 'package:crypto/src/digest.dart';
+import 'package:build/src/resource/resource.dart';
+import 'package:build/src/asset/id.dart';
+import 'package:build/src/analyzer/resolver.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'dart:convert';
+
+import 'dart:async';
+
 import 'package:dart_style/dart_style.dart';
+import 'package:glob/glob.dart';
 import 'package:merging_builder/merging_builder.dart';
 import 'package:merging_builder/src/builders/formatter.dart';
 import 'package:source_gen/source_gen.dart';
+import 'package:build/build.dart' show BuildStep;
 
 /// Mock builder with methods: [mergedContent] and [_combinedStream].
 /// Used for testing purposes.
 class MockMergingBuilder<T> {
   MockMergingBuilder({
-    this.generator,
-    this.header,
-    this.footer,
-    this.libraries,
-    Formatter formatOutput,
+    required this.generator,
+    this.header = '',
+    this.footer = '',
+    required this.libraries,
+    Formatter? formatOutput,
   }) : _formatOutput = formatOutput ?? DartFormatter().format;
 
   final MergingGenerator<T, dynamic> generator;
@@ -38,7 +49,7 @@ class MockMergingBuilder<T> {
     buffer.writeln();
 
     // Add footer.
-    if (footer != null) buffer.writeln(footer);
+    buffer.writeln(footer);
 
     // Format output.
     return _formatOutput(buffer.toString());
@@ -49,11 +60,86 @@ class MockMergingBuilder<T> {
   /// by iterating over each file asset.
   Stream<T> _combineStreams() async* {
     for (final library in libraries) {
-      final streamOfT = await generator.generateStream(library, null);
+      final streamOfT = generator.generateStream(library, MockBuildStep());
       // Combining all objects of type [T] into a stream.
       await for (final T t in streamOfT) {
         yield t;
       }
     }
   }
 }
+
+class MockBuildStep extends BuildStep {
+  @override
+  Future<bool> canRead(AssetId id) {
+    // TODO: implement canRead
+    throw UnimplementedError();
+  }
+
+  @override
+  Future<Digest> digest(AssetId id) {
+    // TODO: implement digest
+    throw UnimplementedError();
+  }
+
+  @override
+  Future<T> fetchResource<T>(Resource<T> resource) {
+    // TODO: implement fetchResource
+    throw UnimplementedError();
+  }
+
+  @override
+  Stream<AssetId> findAssets(Glob glob) {
+    // TODO: implement findAssets
+    throw UnimplementedError();
+  }
+
+  @override
+  // TODO: implement inputId
+  AssetId get inputId => throw UnimplementedError();
+
+  @override
+  // TODO: implement inputLibrary
+  Future<LibraryElement> get inputLibrary => throw UnimplementedError();
+
+  @override
+  Future<List<int>> readAsBytes(AssetId id) {
+    // TODO: implement readAsBytes
+    throw UnimplementedError();
+  }
+
+  @override
+  Future<String> readAsString(AssetId id, {Encoding encoding = utf8}) {
+    // TODO: implement readAsString
+    throw UnimplementedError();
+  }
+
+  @override
+  void reportUnusedAssets(Iterable<AssetId> ids) {
+    // TODO: implement reportUnusedAssets
+  }
+
+  @override
+  // TODO: implement resolver
+  Resolver get resolver => throw UnimplementedError();
+
+  @override
+  T trackStage<T>(String label, T Function() action,
+      {bool isExternal = false}) {
+    // TODO: implement trackStage
+    throw UnimplementedError();
+  }
+
+  @override
+  Future<void> writeAsBytes(AssetId id, FutureOr<List<int>> bytes) {
+    // TODO: implement writeAsBytes
+    throw UnimplementedError();
+  }
+
+  @override
+  Future<void> writeAsString(AssetId id, FutureOr<String> contents,
+      {Encoding encoding = utf8}) {
+    // TODO: implement writeAsString
+    throw UnimplementedError();
+  }
+}

example/researcher/test/src/mock_builders/mock_standalone_builder.dart

@@ -1,5 +1,4 @@
 import 'package:merging_builder/merging_builder.dart';
-import 'package:meta/meta.dart';
 import 'package:source_gen/source_gen.dart';
 
 /// StandaloneBuilder for testing purposes with
@@ -8,7 +7,7 @@ class MockStandaloneBuilder extends StandaloneBuilder<LibDir> {
   MockStandaloneBuilder({
     String inputFiles = 'lib/*.dart',
     String outputFiles = 'lib/standalone_(*).dart',
-    @required Generator generator,
+    required Generator generator,
     String header = '',
     String footer = '',
   }) : super(

example/researcher_builder/lib/src/generators/add_names_generator.dart

@@ -35,7 +35,7 @@ class AddNamesGenerator extends MergingGenerator<List<String>, AddNames> {
       }
       return result;
     }
-    return null;
+    return <String>['Could not read name'];
   }
 
   /// Returns the merged content.

example/researcher_builder/lib/src/generators/add_numbers_generator.dart

@@ -26,9 +26,11 @@ class AddNumbersGenerator extends MergingGenerator<num, AddNumbers> {
     BuildStep buildStep,
   ) {
     if (element is ClassElement) {
-      return element.getField('number')?.computeConstantValue()?.toIntValue();
+      return element.getField('number')?.computeConstantValue()?.toIntValue() ??
+          double.nan;
+    } else {
+      return double.nan;
     }
-    return null;
   }
 
   /// Returns merged content.

example/researcher_builder/lib/src/generators/assistant_generator.dart

@@ -33,6 +33,6 @@ class AssistantGenerator extends GeneratorForAnnotation<AddNames> {
       }
       return 'final String assistants = \'${result.join(', ')}\';';
     }
-    return null;
+    return '';
   }
 }

example/researcher_builder/pubspec.yaml

@@ -1,19 +1,26 @@
 name: researcher_builder
-description:
-  Example demonstrating how to use the library merging_builder.
+
+description: Example demonstrating how to use the library merging_builder.
 
 environment:
-  sdk: '>=2.8.1 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
-  analyzer: ^0.39.12
-  build: ^1.3.0
-  build_config: ^0.4.2
   merging_builder:
     path: ../../
   researcher:
     path: ../researcher
-  source_gen: ^0.9.5
-  quote_buffer: ^0.1.5
+  analyzer: ^1.2.0
+  build: ^2.0.0
+  build_config: ^0.4.7
+  quote_buffer: ^0.2.2
+  source_gen: ^0.9.10+4
+
+dev_dependencies: null
 
-dev_dependencies:
+dependency_overrides:
+  source_gen:
+    git:
+      url: [email protected]:dart-lang/source_gen.git
+      ref: master
+      path: source_gen

lib/src/builders/merging_builder.dart

@@ -2,7 +2,6 @@ import 'dart:async';
 import 'package:build/build.dart';
 import 'package:exception_templates/exception_templates.dart';
 import 'package:glob/glob.dart';
-import 'package:meta/meta.dart';
 import 'package:path/path.dart' as path show equals;
 import 'package:source_gen/source_gen.dart' show LibraryReader;
 
@@ -18,31 +17,31 @@ import 'synthetic_input.dart';
 /// - Requires a generator extending [MergingGenerator].
 class MergingBuilder<T, S extends SyntheticInput> extends SyntheticBuilder<S> {
   /// Constructs a [MergingBuilder] object.
-  ///
-  /// - [inputFiles] defaults to: `'lib/*.dart'`.
-  ///
-  /// - [outputFile] defaults to: `'lib/merged_output.dart'`.
-  ///
-  /// - [generator] extending [MergingGenerator<T, A>] is required.
-  ///
-  /// - [header] defaults to: `''`
-  ///
-  /// - [footer] defaults to : `''`
-  ///
-  /// - [formatOutput] defaults to: `DartFormatter().format`.
+  /// * `inputFiles`: Path to the input files relative to the
+  /// package root directory. Glob-style syntax is
+  /// allowed, defaults to: `'lib/*.dart'`.
+  /// * `outputFile`: defaults to: `'lib/merged_output.dart'`.
+  /// * `generator`: Must extend `MergingGenerator<T, A>`.
+  /// * `header`: `String` that will be inserted at the top of the
+  /// generated file below the 'DO NOT EDIT' warning message.
+  /// * `footer`: String that will be inserted at the very bottom of the
+  /// generated file.
+  /// * `formatter`: A function with signature `String Function(String input)`
+  /// that is used to format the generated source code.
+  /// The default formatter is: `DartFormatter().format`.
   MergingBuilder({
     String inputFiles = 'lib/*.dart',
     this.outputFile = 'lib/merged_output.dart',
-    @required this.generator,
+    required this.generator,
     String header = '',
     String footer = '',
     this.sortAssets = false,
-    Formatter formatOutput,
+    Formatter? formatter,
   }) : super(
           inputFiles: inputFiles,
           header: header,
           footer: footer,
-          formatOutput: formatOutput,
+          formatter: formatter,
         );
 
   /// Path to output file relative to the package root directory.
@@ -108,7 +107,7 @@ class MergingBuilder<T, S extends SyntheticInput> extends SyntheticBuilder<S> {
   /// by iterating over each library file asset.
   Stream<T> _combineStreams(
     BuildStep buildStep,
-    List<AssetId> libraryAssetIds,
+    Iterable<AssetId> libraryAssetIds,
   ) async* {
     // Accessing libraries.
     for (final libraryAssetId in libraryAssetIds) {
@@ -119,7 +118,7 @@ class MergingBuilder<T, S extends SyntheticInput> extends SyntheticBuilder<S> {
       // Calling generator.generateStream. An object of type [T] is
       // emitted for each class defined in library that is annotated with [A].
       log.fine('Running ${generator.runtimeType} on: ${libraryAssetId.path}.');
-      final streamOfT = await generator.generateStream(library, buildStep);
+      final streamOfT = generator.generateStream(library, buildStep);
 
       // Combining all objects of type [T] into a stream.
       await for (final T t in streamOfT) {