Merge pull request #24 from davidmorgan/switch-to-oo

Refactor to objects. Fix duplicate detection.

Author: davidmorgan

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 1.0.0
+
+- API now stable.
+- Refactor generator to split into logical classes.
+- Fix "watch mode": check for duplicate identifiers per library.
+
 ## 0.2.2
 
 - Improve error output on failure to generate.

enum_class/pubspec.yaml

@@ -1,5 +1,5 @@
 name: enum_class
-version: 0.2.2
+version: 1.0.0
 description: >
   Dart classes as enums. This library is the runtime dependency.
 authors:

enum_class_generator/lib/enum_class_generator.dart

@@ -8,265 +8,18 @@ import 'dart:async';
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:build/build.dart';
-import 'package:quiver/iterables.dart' show concat;
+import 'package:enum_class_generator/src/source_library.dart';
 import 'package:source_gen/source_gen.dart';
 
 /// Generator for Enum Classes.
 ///
 /// See https://github.com/google/enum_class.dart/tree/master/example for how
 /// to use it.
 class EnumClassGenerator extends Generator {
-  Set<String> _usedGeneratedIdentifiers = new Set<String>();
-
   @override
   Future<String> generate(Element element, BuildStep buildStep) async {
-    if (element is! ClassElement) {
-      return null;
-    }
-    final classElement = element as ClassElement;
-    final enumName = classElement.displayName;
-
-    if (classElement.supertype.displayName != 'EnumClass') {
-      // Maybe they're trying to use EnumClass but forgot to import the library.
-      if (classElement
-          .computeNode()
-          .toSource()
-          .contains('class ${classElement.displayName} extends EnumClass')) {
-        throw _makeError(
-            ["Import EnumClass: import 'package:enum_class/enum_class.dart';"]);
-      } else {
-        return null;
-      }
-    }
-
-    final libraryName = classElement.library.displayName;
-    final fields = _getApplicableFields(classElement);
-    final errors = concat([
-      _checkPart(classElement),
-      _checkFields(libraryName, fields),
-      _checkConstructor(classElement),
-      _checkValuesGetter(libraryName, classElement),
-      _checkValueOf(libraryName, classElement)
-    ]).toList();
-
-    final mixinElement = classElement.library.getType(enumName + 'Mixin');
-    final shouldGenerateMixin = mixinElement != null;
-    if (shouldGenerateMixin) {
-      final expectedCode =
-          'abstract class ${enumName}Mixin = Object with _\$${enumName}Mixin;';
-      if (mixinElement.computeNode().toString() != expectedCode) {
-        errors.add('Remove mixin or declare using exactly: $expectedCode');
-      }
-    }
-
-    if (errors.isNotEmpty) {
-      throw _makeError(errors);
-    }
-
-    return _generateCode(classElement, enumName, fields, shouldGenerateMixin);
-  }
-
-  Iterable<String> _checkPart(ClassElement classElement) {
-    final fileName =
-        classElement.library.source.shortName.replaceAll('.dart', '');
-    final expectedCode = "part '$fileName.g.dart';";
-    final alternativeExpectedCode = 'part "$fileName.g.dart";';
-    final source = classElement.library.source.contents.data;
-    return source.contains(expectedCode) ||
-            source.contains(alternativeExpectedCode)
-        ? <String>[]
-        : <String>['Import generated part: $expectedCode'];
-  }
-
-  Iterable<FieldElement> _getApplicableFields(ClassElement classElement) {
-    final enumName = classElement.displayName;
-    final result = <FieldElement>[];
-    for (final field in classElement.fields) {
-      final type = field.getter.returnType.displayName;
-      if (!field.isSynthetic && (type == enumName || type == 'dynamic')) {
-        result.add(field);
-      }
-    }
-    return result;
-  }
-
-  Iterable<String> _checkFields(
-      String libraryName, Iterable<FieldElement> fields) {
-    final result = <String>[];
-    for (final field in fields) {
-      final fieldName = field.displayName;
-      if (field.getter.returnType.displayName == 'dynamic') {
-        result.add('Specify a type for field "$fieldName".');
-        continue;
-      } else if (!field.isConst && !field.isStatic) {
-        result.add('Make field "$fieldName" static const.');
-        continue;
-      } else if (!field.isConst) {
-        result.add('Make field "$fieldName" const.');
-        continue;
-      }
-
-      if (!field.computeNode().toString().startsWith('$fieldName = _\$')) {
-        result
-            .add('Initialize field "$fieldName" with a value starting "_\$".');
-      }
-
-      final identifier = _getGeneratedIdentifier(field);
-      result.addAll(
-          _checkAndRegisterGeneratedIdentifier(libraryName, identifier));
-    }
-    return result;
-  }
-
-  Iterable<String> _checkConstructor(ClassElement classElement) {
-    final enumName = classElement.displayName;
-    final expectedCode = 'const $enumName._(String name) : super(name);';
-    return classElement.constructors.length == 1 &&
-            classElement.constructors.single.computeNode().toString() ==
-                expectedCode
-        ? <String>[]
-        : <String>['Have exactly one constructor: $expectedCode'];
-  }
-
-  Iterable<String> _checkValuesGetter(
-      String libraryName, ClassElement classElement) {
-    final enumName = classElement.displayName;
-    final valuesIdentifier = _getValuesIdentifier(classElement, enumName);
-    final result = <String>[];
-    if (valuesIdentifier == null) {
-      result.add(
-          'Add getter: static BuiltSet<$enumName> get values => _\$values');
-    } else {
-      result.addAll(
-          _checkAndRegisterGeneratedIdentifier(libraryName, valuesIdentifier));
-    }
-    return result;
-  }
-
-  Iterable<String> _checkValueOf(
-      String libraryName, ClassElement classElement) {
-    final enumName = classElement.displayName;
-    final valueOfIdentifier = _getValueOfIdentifier(classElement, enumName);
-    final result = <String>[];
-    if (valueOfIdentifier == null) {
-      result.add('Add method: '
-          'static $enumName valueOf(String name) => _\$valueOf(name)');
-    } else {
-      result.addAll(
-          _checkAndRegisterGeneratedIdentifier(libraryName, valueOfIdentifier));
-    }
-    return result;
-  }
-
-  Iterable<String> _checkAndRegisterGeneratedIdentifier(
-      String libraryName, String identifier) {
-    final result = <String>[];
-    final scopedIdentifier = '$libraryName.$identifier';
-    if (_usedGeneratedIdentifiers.contains(scopedIdentifier)) {
-      result
-          .add('Generated identifier "_\$$identifier" is used multiple times in'
-              ' $libraryName, change to something else.');
-    } else {
-      _usedGeneratedIdentifiers.add(scopedIdentifier);
-    }
-    return result;
-  }
-
-  String _generateCode(ClassElement classElement, String enumName,
-      Iterable<FieldElement> fields, bool generateMixin) {
-    final result = new StringBuffer();
-
-    for (final field in fields) {
-      final fieldName = field.displayName;
-      result.writeln('const $enumName _\$${_getGeneratedIdentifier(field)} = '
-          'const $enumName._(\'$fieldName\');');
-    }
-
-    result.writeln('');
-
-    final valueOf = _getValueOfIdentifier(classElement, enumName);
-    result.writeln('$enumName _\$$valueOf(String name) {'
-        'switch (name) {');
-    for (final field in fields) {
-      final fieldName = field.displayName;
-      result.writeln(
-          'case \'$fieldName\': return _\$${_getGeneratedIdentifier(field)};');
-    }
-    result.writeln('default: throw new ArgumentError(name);');
-    result.writeln('}}');
-
-    result.writeln('');
-
-    final values = _getValuesIdentifier(classElement, enumName);
-    result.writeln('final BuiltSet<$enumName> _\$$values ='
-        'new BuiltSet<$enumName>(const [');
-    for (final field in fields) {
-      result.writeln('_\$${_getGeneratedIdentifier(field)},');
-    }
-    result.writeln(']);');
-
-    if (generateMixin)
-      result.write(_generateMixin(enumName, fields, valueOf, values));
-
-    return result.toString();
-  }
-
-  String _generateMixin(String enumName, Iterable<FieldElement> fields,
-      String valueOfIdentifier, String valuesIdentifier) {
-    final result = new StringBuffer();
-
-    result.writeln('class _\$${enumName}Meta {');
-    result.writeln('const _\$${enumName}Meta();');
-    for (final field in fields) {
-      final fieldName = field.displayName;
-      result.writeln('$enumName get $fieldName => _\$${_getGeneratedIdentifier(
-          field)};');
-    }
-    result.writeln(
-        '$enumName valueOf(String name) => _\$$valueOfIdentifier(name);');
-    result.writeln('BuiltSet<$enumName> get values => _\$$valuesIdentifier;');
-    result.writeln('}');
-    result.writeln('abstract class _\$${enumName}Mixin {');
-    result.writeln(
-        '_\$${enumName}Meta get $enumName => const _\$${enumName}Meta();');
-    result.writeln('}');
-
-    return result.toString();
-  }
-
-  String _getGeneratedIdentifier(FieldElement field) {
-    final fieldName = field.displayName;
-    return field.computeNode().toString().substring('$fieldName = _\$'.length);
-  }
-
-  String _getValueOfIdentifier(ClassElement classElement, String enumName) {
-    final getter = classElement.getMethod('valueOf');
-    if (getter == null) return null;
-    final source = getter.computeNode().toSource();
-    final matches = new RegExp(r'static ' +
-            enumName +
-            r' valueOf\(String name\) \=\> \_\$(\w+)\(name\)\;')
-        .allMatches(source);
-    return matches.isEmpty ? null : matches.first.group(1);
-  }
-
-  String _getValuesIdentifier(ClassElement classElement, String enumName) {
-    final getter = classElement.getGetter('values');
-    if (getter == null) return null;
-    final source = getter.computeNode().toSource();
-    final matches = new RegExp(
-            r'static BuiltSet<' + enumName + r'> get values => _\$(\w+)\;')
-        .allMatches(source);
-    return matches.isEmpty ? null : matches.first.group(1);
-  }
-
-  InvalidGenerationSourceError _makeError(Iterable<String> todos) {
-    final message = new StringBuffer(
-        'Please make the following changes to use EnumClass:\n');
-    for (var i = 0; i != todos.length; ++i) {
-      message.write('\n${i + 1}. ${todos.elementAt(i)}');
-    }
+    if (element is! LibraryElement) return null;
 
-    return new InvalidGenerationSourceError(message.toString());
+    return new SourceLibrary.fromLibraryElement(element).generateCode();
   }
 }

enum_class_generator/lib/src/library_elements.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2016, Google Inc. 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:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/visitor.dart';
+import 'package:built_collection/built_collection.dart';
+
+/// Tools for [LibraryElement]s.
+class LibraryElements {
+  static BuiltList<ClassElement> getClassElements(
+      LibraryElement libraryElement) {
+    final result = new _GetClassesVisitor();
+    libraryElement.visitChildren(result);
+    return new BuiltList<ClassElement>(result.classElements);
+  }
+}
+
+/// Visitor that gets all [ClassElement]s.
+class _GetClassesVisitor extends SimpleElementVisitor {
+  final List<ClassElement> classElements = new List<ClassElement>();
+
+  @override
+  visitClassElement(ClassElement element) {
+    classElements.add(element);
+  }
+
+  @override
+  visitCompilationUnitElement(CompilationUnitElement element) {
+    element.visitChildren(this);
+  }
+}