Cleanup for dart 2 and add unit testing with --preview-dart-2 (#1669)

* Cleanup for dart 2 and add unit testing with --preview-dart-2

* Try to hack around Windows failures

* Clarify how MultiFutureTracker works

* Remove extra attempt to find categories

Author: jcollins-g

lib/src/dartdoc_options.dart

@@ -634,7 +634,7 @@ abstract class _DartdocArgOption<T> implements DartdocOption<T> {
       retval = double.tryParse(_argResults[argName]) as T;
       if (retval == null) _throwErrorForTypes(_argResults[argName]);
     } else if (_isMapString) {
-      retval = {} as T;
+      retval = <String, String>{} as T;
       for (String pair in _argResults[argName]) {
         List<String> pairList = pair.split('::');
         if (pairList.length != 2) {
@@ -788,7 +788,9 @@ class _FileDartdocOptions extends DartdocOptions {
       _categoryOrder = [];
       if (_dartdocOptions.containsKey('categoryOrder')) {
         if (_dartdocOptions['categoryOrder'] is YamlList) {
-          _categoryOrder.addAll(_dartdocOptions['categoryOrder']);
+          _categoryOrder.addAll(_dartdocOptions['categoryOrder']
+              .map((c) => c.toString())
+              .cast<String>());
         } else {
           logWarning('${_path}: categoryOrder must be a list (ignoring)');
         }

lib/src/element_type.dart

@@ -254,7 +254,7 @@ abstract class CallableElementTypeMixin implements ParameterizedElementType {
   @override
   // TODO(jcollins-g): Rewrite this and improve object model so this doesn't
   // require type checking everywhere.
-  Iterable<DefinedElementType> get typeArguments {
+  Iterable<ElementType> get typeArguments {
     if (_typeArguments == null) {
       Iterable<DartType> dartTypeArguments;
       if (type.typeFormals.isEmpty &&

lib/src/html/html_generator_instance.dart

@@ -8,6 +8,7 @@ import 'dart:io' show File;
 
 import 'package:collection/collection.dart' show compareNatural;
 import 'package:dartdoc/src/model_utils.dart';
+import 'package:mustache4dart/mustache4dart.dart';
 import 'package:path/path.dart' as pathLib;
 
 import '../logging.dart';

lib/src/html/resource_loader.dart

@@ -28,7 +28,6 @@ Future<List<int>> loadAsBytes(String path) async {
     throw new ArgumentError('path must begin with package:');
   }
 
-  var uri = Uri.parse(path);
-
+  Uri uri = Uri.parse(path);
   return await ResourceLoader.defaultLoader.readAsBytes(uri);
 }

lib/src/html/templates.dart

@@ -11,9 +11,6 @@ import 'package:mustache4dart/mustache4dart.dart';
 
 import 'resource_loader.dart' as loader;
 
-typedef String TemplateRenderer(context,
-    {bool assumeNullNonExistingProperty, bool errorOnMissingProperty});
-
 const _partials = const <String>[
   'callable',
   'callable_multiline',
@@ -112,7 +109,7 @@ class Templates {
 
     Future<TemplateRenderer> _loadTemplate(String templatePath) async {
       String templateContents = await _getTemplateFile(templatePath);
-      return compile(templateContents, partial: _partial) as TemplateRenderer;
+      return compile(templateContents, partial: _partial);
     }
 
     var indexTemplate = await _loadTemplate('index.html');

lib/src/io_utils.dart

@@ -6,6 +6,7 @@
 library dartdoc.io_utils;
 
 import 'dart:async';
+import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
 
@@ -65,6 +66,36 @@ final newLinePartOfRegexp = new RegExp('\npart of ');
 
 final RegExp quotables = new RegExp(r'[ "\r\n\$]');
 
+/// Best used with Future<void>.
+class MultiFutureTracker<T> {
+  /// Approximate maximum number of simultaneous active Futures.
+  final int parallel;
+
+  final Queue<Future<T>> _queue = new Queue();
+
+  MultiFutureTracker(this.parallel);
+
+  /// Adds a Future to the queue of outstanding Futures, and returns a Future
+  /// that completes only when the number of Futures outstanding is <= parallel.
+  /// That can be extremely brief and there's no longer a guarantee after that
+  /// point that another async task has not added a Future to the list.
+  void addFuture(Future<T> future) async {
+    _queue.add(future);
+    future.then((f) => _queue.remove(future));
+    await _waitUntil(parallel);
+  }
+
+  /// Wait until fewer or equal to this many Futures are outstanding.
+  void _waitUntil(int max) async {
+    while (_queue.length > max) {
+      await Future.any(_queue);
+    }
+  }
+
+  /// Wait until all futures added so far have completed.
+  void wait() async => await _waitUntil(0);
+}
+
 class SubprocessLauncher {
   final String context;
   final Map<String, String> environment;
@@ -126,6 +157,8 @@ class SubprocessLauncher {
       return line.split('\n');
     }
 
+    Process process = await Process.start(executable, arguments,
+        workingDirectory: workingDirectory, environment: environment);
     stderr.write('$prefix+ ');
     if (workingDirectory != null) stderr.write('(cd "$workingDirectory" && ');
     if (environment != null) {
@@ -150,9 +183,6 @@ class SubprocessLauncher {
     }
     if (workingDirectory != null) stderr.write(')');
     stderr.write('\n');
-    Process process = await Process.start(executable, arguments,
-        workingDirectory: workingDirectory, environment: environment);
-
     _printStream(process.stdout, stdout, prefix: prefix, filter: jsonCallback);
     _printStream(process.stderr, stderr, prefix: prefix, filter: jsonCallback);
     await process.exitCode;

lib/src/model.dart

@@ -443,7 +443,7 @@ class Class extends ModelElement
       : super(element, library, packageGraph, null) {
     _mixins = _cls.mixins
         .map((f) {
-          ElementType t = new ElementType.from(f, packageGraph);
+          DefinedElementType t = new ElementType.from(f, packageGraph);
           return t;
         })
         .where((mixin) => mixin != null)
@@ -454,7 +454,7 @@ class Class extends ModelElement
     }
 
     _interfaces = _cls.interfaces
-        .map((f) => new ElementType.from(f, packageGraph))
+        .map((f) => new ElementType.from(f, packageGraph) as DefinedElementType)
         .toList(growable: false);
   }
 
@@ -605,7 +605,7 @@ class Class extends ModelElement
     if (_constructors != null) return _constructors;
 
     _constructors = _cls.constructors.map((e) {
-      return new ModelElement.from(e, library, packageGraph);
+      return new ModelElement.from(e, library, packageGraph) as Constructor;
     }).toList(growable: true)
       ..sort(byName);
 
@@ -818,9 +818,11 @@ class Class extends ModelElement
 
   List<Operator> get operators {
     if (_operators != null) return _operators;
-
-    _operators = _methods.where((m) => m.isOperator).toList(growable: false)
-      ..sort(byName);
+    _operators = _methods
+        .where((m) => m.isOperator)
+        .cast<Operator>()
+        .toList(growable: false)
+          ..sort(byName);
     _genPageOperators.addAll(_operators);
 
     return _operators;
@@ -935,7 +937,9 @@ class Class extends ModelElement
     if (_fields != null) return _fields;
     _fields = [];
     Set<PropertyAccessorElement> inheritedAccessors = new Set()
-      ..addAll(_inheritedElements.where((e) => e is PropertyAccessorElement));
+      ..addAll(_inheritedElements
+          .where((e) => e is PropertyAccessorElement)
+          .cast<PropertyAccessorElement>());
 
     // This structure keeps track of inherited accessors, allowing lookup
     // by field name (stripping the '=' from setters).
@@ -1041,7 +1045,7 @@ class Class extends ModelElement
     if (_allMethods != null) return _allMethods;
 
     _allMethods = _cls.methods.map((e) {
-      return new ModelElement.from(e, library, packageGraph);
+      return new ModelElement.from(e, library, packageGraph) as Method;
     }).toList(growable: false)
       ..sort(byName);
 
@@ -1052,7 +1056,7 @@ class Class extends ModelElement
   @override
   List<TypeParameter> get typeParameters => _cls.typeParameters.map((f) {
         var lib = new Library(f.enclosingElement.library, packageGraph);
-        return new ModelElement.from(f, lib, packageGraph);
+        return new ModelElement.from(f, lib, packageGraph) as TypeParameter;
       }).toList();
 
   @override
@@ -1162,7 +1166,7 @@ abstract class Documentable extends Nameable {
 abstract class Categorization implements ModelElement {
   @override
   String _buildDocumentationLocal() {
-    _rawDocs = super._buildDocumentationLocal();
+    _rawDocs = _buildDocumentationBase();
     _rawDocs = _stripAndSetDartdocCategory(_rawDocs);
     return _rawDocs;
   }
@@ -1282,7 +1286,7 @@ class Enum extends Class {
         .instanceProperties
         .map((Field p) => new ModelElement.from(
             p.element, p.library, p.packageGraph,
-            getter: p.getter, setter: p.setter))
+            getter: p.getter, setter: p.setter) as EnumField)
         .toList(growable: false);
   }
 
@@ -1720,7 +1724,7 @@ abstract class GetterSetterCombo implements ModelElement {
 
 class Library extends ModelElement with Categorization {
   List<Class> _classes;
-  List<Class> _enums;
+  List<Enum> _enums;
   List<ModelFunction> _functions;
   List<Typedef> _typeDefs;
   List<TopLevelVariable> _variables;
@@ -1931,12 +1935,13 @@ class Library extends ModelElement with Categorization {
 
   List<Class> get enums {
     if (_enums != null) return _enums;
-
     List<ClassElement> enumClasses = [];
     enumClasses.addAll(_exportedNamespace.definedNames.values
-        .where((element) => element is ClassElement && element.isEnum));
+        .where((e) => e is ClassElement)
+        .cast<ClassElement>()
+        .where((element) => element.isEnum));
     _enums = enumClasses
-        .map((e) => new ModelElement.from(e, this, packageGraph))
+        .map((e) => new ModelElement.from(e, this, packageGraph) as Enum)
         .toList(growable: false)
           ..sort(byName);
 
@@ -1966,10 +1971,11 @@ class Library extends ModelElement with Categorization {
       elements.addAll(cu.functions);
     }
     elements.addAll(_exportedNamespace.definedNames.values
-        .where((element) => element is FunctionElement));
+        .where((e) => e is FunctionElement)
+        .cast<FunctionElement>());
 
     _functions = elements.map((e) {
-      return new ModelElement.from(e, this, packageGraph);
+      return new ModelElement.from(e, this, packageGraph) as ModelFunction;
     }).toList(growable: false)
       ..sort(byName);
 
@@ -2080,9 +2086,10 @@ class Library extends ModelElement with Categorization {
     }
 
     elements.addAll(_exportedNamespace.definedNames.values
-        .where((element) => element is FunctionTypeAliasElement));
+        .where((e) => e is FunctionTypeAliasElement)
+        .cast<FunctionTypeAliasElement>());
     _typeDefs = elements
-        .map((e) => new ModelElement.from(e, this, packageGraph))
+        .map((e) => new ModelElement.from(e, this, packageGraph) as Typedef)
         .toList(growable: false)
           ..sort(byName);
 
@@ -2106,10 +2113,12 @@ class Library extends ModelElement with Categorization {
     }
 
     types.addAll(_exportedNamespace.definedNames.values
-        .where((element) => element is ClassElement && !element.isEnum));
+        .where((e) => e is ClassElement)
+        .cast<ClassElement>()
+        .where((element) => !element.isEnum));
 
     _classes = types
-        .map((e) => new ModelElement.from(e, this, packageGraph))
+        .map((e) => new ModelElement.from(e, this, packageGraph) as Class)
         .toList(growable: false)
           ..sort(byName);
 
@@ -2335,7 +2344,7 @@ class Method extends ModelElement
 
   void _calcTypeParameters() {
     typeParameters = _method.typeParameters.map((f) {
-      return new ModelElement.from(f, library, packageGraph);
+      return new ModelElement.from(f, library, packageGraph) as TypeParameter;
     }).toList();
   }
 
@@ -2845,7 +2854,10 @@ abstract class ModelElement extends Canonicalization
     return docFrom;
   }
 
-  String _buildDocumentationLocal() {
+  String _buildDocumentationLocal() => _buildDocumentationBase();
+
+  /// Separate from _buildDocumentationLocal for overriding.
+  String _buildDocumentationBase() {
     assert(_rawDocs == null);
     if (config.dropTextFrom.contains(element.library.name)) {
       _rawDocs = '';
@@ -3245,8 +3257,9 @@ abstract class ModelElement extends Canonicalization
       }
 
       _parameters = new UnmodifiableListView<Parameter>(params
-          .map((p) => new ModelElement.from(p, library, packageGraph))
-          .toList() as Iterable<Parameter>);
+          .map((p) =>
+              new ModelElement.from(p, library, packageGraph) as Parameter)
+          .toList());
     }
     return _parameters;
   }
@@ -3651,7 +3664,7 @@ class ModelFunctionTyped extends ModelElement
 
   void _calcTypeParameters() {
     typeParameters = _func.typeParameters.map((f) {
-      return new ModelElement.from(f, library, packageGraph);
+      return new ModelElement.from(f, library, packageGraph) as TypeParameter;
     }).toList();
   }
 
@@ -3835,16 +3848,16 @@ class PackageGraph extends Canonicalization
   @override
   final DartdocConfig config;
 
-  Map<String, Map<String, List<Map<String, dynamic>>>> __crossdartJson;
+  Map<String, Map<String, dynamic>> __crossdartJson;
   // TODO(jcollins-g): move to [Package]
-  Map<String, Map<String, List<Map<String, dynamic>>>> get crossdartJson {
+  Map<String, Map<String, dynamic>> get crossdartJson {
     if (__crossdartJson == null) {
       // TODO(jcollins-g): allow crossdart.json location to be configurable
       var crossdartFile =
           new File(pathLib.join(config.inputDir.path, "crossdart.json"));
       if (crossdartFile.existsSync()) {
-        var __crossdartJsonTmp = json.decode(crossdartFile.readAsStringSync())
-            as Map<String, Map<String, List<Map<String, dynamic>>>>;
+        Map<String, dynamic> __crossdartJsonTmp =
+            json.decode(crossdartFile.readAsStringSync());
         __crossdartJson = {};
         for (String key in __crossdartJsonTmp.keys) {
           __crossdartJson[pathLib.canonicalize(key)] = __crossdartJsonTmp[key];
@@ -4480,8 +4493,10 @@ class PackageGraph extends Canonicalization
       // for an inherited element whose defining Class is not canonical.
       if (matches.length > 1 && preferredClass != null) {
         // Search for matches inside our superchain.
-        List<Class> superChain =
-            preferredClass.superChain.map((et) => et.element).toList();
+        List<Class> superChain = preferredClass.superChain
+            .map((et) => et.element)
+            .cast<Class>()
+            .toList();
         superChain.add(preferredClass);
         matches.removeWhere((me) =>
             !superChain.contains((me as EnclosedElement).enclosingElement));
@@ -5024,7 +5039,7 @@ abstract class TypeParameters implements ModelElement {
   }
 
   @override
-  DefinedElementType get modelType => super.modelType;
+  DefinedElementType get modelType;
 
   List<TypeParameter> get typeParameters;
 }
@@ -5158,7 +5173,7 @@ class Typedef extends ModelElement
 
   @override
   List<TypeParameter> get typeParameters => _typedef.typeParameters.map((f) {
-        return new ModelElement.from(f, library, packageGraph);
+        return new ModelElement.from(f, library, packageGraph) as TypeParameter;
       }).toList();
 }
 

lib/src/model_utils.dart

@@ -140,7 +140,7 @@ String stripIndentFromSource(String source) {
 /// Add links to crossdart.info to the given source fragment
 String crossdartifySource(
     String inputPath,
-    Map<String, Map<String, List<Map<String, dynamic>>>> json,
+    Map<String, Map<String, dynamic>> json,
     String source,
     Element element,
     int start) {

pubspec.lock

@@ -210,7 +210,7 @@ packages:
       name: mustache4dart
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.1"
   node_preamble:
     dependency: transitive
     description: