Initial cut for a development server

lib/src/codegen/js_codegen.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 ddc.src.codegen.js_codegen;
 
 import 'dart:io' show Directory, File;
 
 import 'package:analyzer/analyzer.dart' hide ConstantEvaluator;
 import 'package:analyzer/src/generated/ast.dart' hide ConstantEvaluator;
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/scanner.dart'
     show StringToken, Token, TokenType;
 import 'package:source_maps/source_maps.dart' as srcmaps show Printer;
 import 'package:source_maps/source_maps.dart' show SourceMapSpan;
-import 'package:source_span/source_span.dart' show SourceLocation;
 import 'package:path/path.dart' as path;
 
 // TODO(jmesserly): import from its own package
 import 'package:dev_compiler/src/js/js_ast.dart' as JS;
 import 'package:dev_compiler/src/js/js_ast.dart' show js;
 
 import 'package:dev_compiler/src/checker/rules.dart';
 import 'package:dev_compiler/src/info.dart';
 import 'package:dev_compiler/src/options.dart';
 import 'package:dev_compiler/src/report.dart';
@@ skipping 938 matching lines @@
     var methods = [];
     for (var node in fields) {
       var name = node.name.name;
       methods.add(new JS.Method(new JS.PropertyName(name),
           js.call('function() { return #; }', _visit(node.initializer)),
           isGetter: true));
 
       // TODO(jmesserly): use a dummy setter to indicate writable.
       if (!node.isFinal) {
         methods.add(new JS.Method(
-            new JS.PropertyName(name), js.call('function() {}'),
+            new JS.PropertyName(name), js.call('function(_) {}'),

[Siggi Cherem (dart-lang), 2015/03/03 01:34:14]

@jmesserly - I thought this change to remove the argument here was on purpose,
but for some reason it's failing for me. Maybe I'm doing something wrong?

I get this error in Chrome v42.0.2311.11:

  Uncaught SyntaxError: Unexpected token )

[Jennifer Messerly, 2015/03/03 02:24:21]

yeah, seems that 1 arg is required for the setter per spec.

             isSetter: true));
       }
     }
 
     return js.statement(
         'dart.defineLazyProperties(#, { # })', [objExpr, methods]);
   }
 
   void _flushLibraryProperties(List<JS.Statement> body) {
     if (_properties.isEmpty) return;
@@ skipping 792 matching lines @@
 
   void enterNode(JS.Node jsNode) {
     AstNode node = jsNode.sourceInformation;
     if (node is CompilationUnit) {
       unit = node;
       uri = _makeRelativeUri(unit.element.source.uri);
       return;
     }
     if (unit == null || node == null || node.offset == -1) return;
 
-    var loc = _location(node.offset);
+    var loc = locationFor(unit, uri, node.offset);
     var name = _getIdentifier(node);
     if (name != null) {
       // TODO(jmesserly): mark only uses the beginning of the span, but
       // we're required to pass this as a valid span.
-      var end = _location(node.end);
+      var end = locationFor(unit, uri, node.end);
       printer.mark(new SourceMapSpan(loc, end, name, isIdentifier: true));
     } else {
       printer.mark(loc);
     }
   }
 
-  SourceLocation _location(int offset) {

[Jennifer Messerly, 2015/03/03 02:24:21]

seems worth keeping this, but simplify impl?

_location(offset) => locationFor(unit, uri, offset);
 

[Siggi Cherem (dart-lang), 2015/03/04 04:44:23]

Done.

-    var lineInfo = unit.lineInfo.getLocation(offset);
-    return new SourceLocation(offset,
-        sourceUrl: uri,
-        line: lineInfo.lineNumber - 1,
-        column: lineInfo.columnNumber - 1);
-  }
-
   Uri _makeRelativeUri(Uri src) {
     return new Uri(path: path.relative(src.path, from: outputDir));
   }
 
   void exitNode(JS.Node jsNode) {
     AstNode node = jsNode.sourceInformation;
     if (node is CompilationUnit) {
       unit = null;
       uri = null;
       return;
     }
     if (unit == null || node == null || node.offset == -1) return;
 
     // TODO(jmesserly): in many cases marking the end will be unncessary.
-    printer.mark(_location(node.end));
+    printer.mark(locationFor(unit, uri, node.end));
   }
 
   String _getIdentifier(AstNode node) {
     if (node is SimpleIdentifier) return node.name;
     return null;
   }
 }