fixes #219, able to compile multiple entry points

lib/src/codegen/code_generator.dart

 // Copyright (c) 2015, 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.
 
 library dev_compiler.src.codegen.code_generator;
 
-import 'dart:io';
-
-import 'package:analyzer/src/generated/ast.dart' show CompilationUnit;
 import 'package:analyzer/src/generated/element.dart'
     show CompilationUnitElement, LibraryElement;
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
 import 'package:path/path.dart' as path;
 
-import 'package:dev_compiler/devc.dart' show AbstractCompiler;
+import 'package:dev_compiler/src/compiler.dart' show AbstractCompiler;
 import 'package:dev_compiler/src/info.dart';
 import 'package:dev_compiler/src/utils.dart' show canonicalLibraryName;
 import 'package:dev_compiler/src/checker/rules.dart';
 import 'package:dev_compiler/src/options.dart' show CodegenOptions;
 
 abstract class CodeGenerator {
   final AbstractCompiler compiler;
-  final String outDir;
-  final Uri root;
   final TypeRules rules;
   final AnalysisContext context;
   final CodegenOptions options;
 
   CodeGenerator(AbstractCompiler compiler)
       : compiler = compiler,
-        outDir = path.absolute(compiler.options.codegenOptions.outputDir),
-        root = compiler.entryPointUri,
         rules = compiler.rules,
         context = compiler.context,
         options = compiler.options.codegenOptions;
 
   /// Return a hash, if any, that can be used for caching purposes. When two
   /// invocations to this function return the same hash, the underlying
   /// code-generator generated the same code.
-  String generateLibrary(LibraryUnit unit, LibraryInfo info);
+  String generateLibrary(LibraryUnit unit);
 
   static List<String> _searchPaths = () {
     // TODO(vsm): Can we remove redundancy with multi_package_resolver logic?
     var packagePaths =
         new String.fromEnvironment('package_paths', defaultValue: null);
     if (packagePaths == null) return null;
     var list = packagePaths.split(',');
     // Normalize the paths.
     list = new List<String>.from(list.map(_dirToPrefix));
     // The current directory is implicitly in the search path.
@@ skipping 56 matching lines @@
           suffix = resolvedDir.substring(prefix.length);
           break;
         }
       }
     }
     assert(suffix != null);
     assert(path.isRelative(suffix));
     return _convertIfPackage(suffix);
   }
 
-  String makeOutputDirectory(LibraryInfo info, CompilationUnit unit) {
-    var suffix = _getOutputDirectory(info.name, unit.element);
-    var fileDir = path.join(outDir, suffix);
-    var dir = new Directory(fileDir);
-    if (!dir.existsSync()) {
-      dir.createSync(recursive: true);
-    }
-    return fileDir;
-  }
-
   static Uri uriFor(LibraryElement lib) {
     var unitElement = lib.definingCompilationUnit;
     var uri = unitElement.source.uri;
     if (uri.scheme == 'dart') return uri;
     if (uri.scheme == 'package') return uri;
     var suffix = _getOutputDirectory(canonicalLibraryName(lib), unitElement);
     suffix = path.join(suffix, uri.pathSegments.last);
     var parts = path.split(suffix);
     var index = parts.indexOf('packages');
     if (index < 0) {
       // Not a package.
       // TODO(leafp) These may need to be adjusted
       // relative to the import location
       return new Uri(path: suffix);
     }
     assert(index == 0);
     return new Uri(
         scheme: 'package', path: path.joinAll(parts.sublist(index + 1)));
   }
 }