lib/json_info_codec.dart - dart2js_info - Git at Google

 // 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.

 /// Converters and codecs for converting between JSON and [Info] classes.

 import 'dart:collection';
 import 'dart:convert';

 import 'package:collection/collection.dart';
 import 'src/util.dart';
 import 'info.dart';

 List<String> _toSortedSerializedIds(
         Iterable<Info> infos, Id Function(Info) getId) =>
     infos.map((i) => getId(i).serializedId).toList()..sort(compareNatural);

 // TODO(sigmund): add unit tests.
 class JsonToAllInfoConverter extends Converter<Map<String, dynamic>, AllInfo> {
   // Using `MashMap` here because it's faster than the default `LinkedHashMap`.
   final Map<String, Info> registry = new HashMap<String, Info>();

   AllInfo convert(Map<String, dynamic> json) {
     registry.clear();

     var result = new AllInfo();
     var elements = json['elements'];
     // TODO(srawlins): Since only the Map values are being extracted below,
     // replace `as` with `cast` when `cast` becomes available in Dart 2.0:
     //
     //     .addAll(elements['library'].values.cast<Map>().map(parseLibrary));
     result.libraries.addAll(
         (elements['library'] as Map).values.map((l) => parseLibrary(l)));
     result.classes
         .addAll((elements['class'] as Map).values.map((c) => parseClass(c)));
     result.functions.addAll(
         (elements['function'] as Map).values.map((f) => parseFunction(f)));

     // TODO(het): Revert this when the dart2js with the new codec is in stable
     if (elements['closure'] != null) {
       result.closures.addAll(
           (elements['closure'] as Map).values.map((c) => parseClosure(c)));
     }
     result.fields
         .addAll((elements['field'] as Map).values.map((f) => parseField(f)));
     result.typedefs.addAll(
         (elements['typedef'] as Map).values.map((t) => parseTypedef(t)));
     result.constants.addAll(
         (elements['constant'] as Map).values.map((c) => parseConstant(c)));

     json['holding'].forEach((k, deps) {
       CodeInfo src = registry[k];
       assert(src != null);
       for (var dep in deps) {
         var target = registry[dep['id']];
         assert(target != null);
         src.uses.add(new DependencyInfo(target, dep['mask']));
       }
     });

     json['dependencies']?.forEach((String k, dependencies) {
       List<String> deps = dependencies;
       result.dependencies[registry[k]] = deps.map((d) => registry[d]).toList();
     });

     result.outputUnits
         .addAll((json['outputUnits'] as List).map((o) => parseOutputUnit(o)));

     result.program = parseProgram(json['program']);

     if (json['deferredFiles'] != null) {
       final deferredFilesMap =
           (json['deferredFiles'] as Map).cast<String, Map<String, dynamic>>();
       for (final library in deferredFilesMap.values) {
         if (library['imports'] != null) {
           // The importMap needs to be typed as <String, List<String>>, but the
           // json parser produces <String, dynamic>.
           final importMap = library['imports'] as Map<String, dynamic>;
           importMap.forEach((prefix, files) {
             importMap[prefix] = (files as List<dynamic>).cast<String>();
           });
           library['imports'] = importMap.cast<String, List<String>>();
         }
       }
       result.deferredFiles = deferredFilesMap;
     }

     // todo: version, etc
     return result;
   }

   OutputUnitInfo parseOutputUnit(Map json) {
     OutputUnitInfo result = parseId(json['id']);
     result
       ..filename = json['filename']
       ..name = json['name']
       ..size = json['size'];
     result.imports
         .addAll((json['imports'] as List).map((s) => s as String) ?? const []);
     return result;
   }

   LibraryInfo parseLibrary(Map json) {
     LibraryInfo result = parseId(json['id']);
     result
       ..name = json['name']
       ..uri = Uri.parse(json['canonicalUri'])
       ..outputUnit = parseId(json['outputUnit'])
       ..size = json['size'];
     for (var child in json['children'].map(parseId)) {
       if (child is FunctionInfo) {
         result.topLevelFunctions.add(child);
       } else if (child is FieldInfo) {
         result.topLevelVariables.add(child);
       } else if (child is ClassInfo) {
         result.classes.add(child);
       } else {
         assert(child is TypedefInfo);
         result.typedefs.add(child);
       }
     }
     return result;
   }

   ClassInfo parseClass(Map json) {
     ClassInfo result = parseId(json['id']);
     result
       ..name = json['name']
       ..parent = parseId(json['parent'])
       ..outputUnit = parseId(json['outputUnit'])
       ..size = json['size']
       ..isAbstract = json['modifiers']['abstract'] == true;
     assert(result is ClassInfo);
     for (var child in json['children'].map(parseId)) {
       if (child is FunctionInfo) {
         result.functions.add(child);
       } else {
         assert(child is FieldInfo);
         result.fields.add(child);
       }
     }
     return result;
   }

   FieldInfo parseField(Map json) {
     FieldInfo result = parseId(json['id']);
     return result
       ..name = json['name']
       ..parent = parseId(json['parent'])
       ..coverageId = json['coverageId']
       ..outputUnit = parseId(json['outputUnit'])
       ..size = json['size']
       ..type = json['type']
       ..inferredType = json['inferredType']
       ..code = parseCode(json['code'])
       ..isConst = json['const'] ?? false
       ..initializer = parseId(json['initializer'])
       ..closures = (json['children'] as List)
           .map<ClosureInfo>((c) => parseId(c))
           .toList();
   }

   ConstantInfo parseConstant(Map json) {
     ConstantInfo result = parseId(json['id']);
     return result
       ..code = parseCode(json['code'])
       ..size = json['size']
       ..outputUnit = parseId(json['outputUnit']);
   }

   TypedefInfo parseTypedef(Map json) {
     TypedefInfo result = parseId(json['id']);
     return result
       ..name = json['name']
       ..parent = parseId(json['parent'])
       ..type = json['type']
       ..size = 0;
   }

   ProgramInfo parseProgram(Map json) {
     var programInfo = new ProgramInfo()
       ..entrypoint = parseId(json['entrypoint'])
       ..size = json['size']
       ..compilationMoment = DateTime.parse(json['compilationMoment'])
       ..dart2jsVersion = json['dart2jsVersion']
       ..noSuchMethodEnabled = json['noSuchMethodEnabled']
       ..isRuntimeTypeUsed = json['isRuntimeTypeUsed']
       ..isIsolateInUse = json['isIsolateInUse']
       ..isFunctionApplyUsed = json['isFunctionApplyUsed']
       ..isMirrorsUsed = json['isMirrorsUsed']
       ..minified = json['minified'];

     // TODO(het): Revert this when the dart2js with the new codec is in stable
     var compilationDuration = json['compilationDuration'];
     if (compilationDuration is String) {
       programInfo.compilationDuration = _parseDuration(compilationDuration);
     } else {
       assert(compilationDuration is int);
       programInfo.compilationDuration =
           new Duration(microseconds: compilationDuration);
     }

     var toJsonDuration = json['toJsonDuration'];
     if (toJsonDuration is String) {
       programInfo.toJsonDuration = _parseDuration(toJsonDuration);
     } else {
       assert(toJsonDuration is int);
       programInfo.toJsonDuration = new Duration(microseconds: toJsonDuration);
     }

     var dumpInfoDuration = json['dumpInfoDuration'];
     if (dumpInfoDuration is String) {
       programInfo.dumpInfoDuration = _parseDuration(dumpInfoDuration);
     } else {
       assert(dumpInfoDuration is int);
       programInfo.dumpInfoDuration =
           new Duration(microseconds: dumpInfoDuration);
     }

     return programInfo;
   }

   /// Parse a string formatted as "XX:YY:ZZ.ZZZZZ" into a [Duration].
   Duration _parseDuration(String duration) {
     if (!duration.contains(':')) {
       return new Duration(milliseconds: int.parse(duration));
     }
     var parts = duration.split(':');
     var hours = double.parse(parts[0]);
     var minutes = double.parse(parts[1]);
     var seconds = double.parse(parts[2]);
     const secondsInMillis = 1000;
     const minutesInMillis = 60 * secondsInMillis;
     const hoursInMillis = 60 * minutesInMillis;
     var totalMillis = secondsInMillis * seconds +
         minutesInMillis * minutes +
         hoursInMillis * hours;
     return new Duration(milliseconds: totalMillis.round());
   }

   FunctionInfo parseFunction(Map json) {
     FunctionInfo result = parseId(json['id']);
     return result
       ..name = json['name']
       ..parent = parseId(json['parent'])
       ..coverageId = json['coverageId']
       ..outputUnit = parseId(json['outputUnit'])
       ..size = json['size']
       ..type = json['type']
       ..returnType = json['returnType']
       ..inferredReturnType = json['inferredReturnType']
       ..parameters =
           (json['parameters'] as List).map((p) => parseParameter(p)).toList()
       ..code = parseCode(json['code'])
       ..sideEffects = json['sideEffects']
       ..inlinedCount = json['inlinedCount']
       ..modifiers =
           parseModifiers(new Map<String, bool>.from(json['modifiers']))
       ..closures = (json['children'] as List)
           .map<ClosureInfo>((c) => parseId(c))
           .toList();
   }

   ParameterInfo parseParameter(Map json) =>
       new ParameterInfo(json['name'], json['type'], json['declaredType']);

   FunctionModifiers parseModifiers(Map<String, bool> json) {
     return new FunctionModifiers(
         isStatic: json['static'] == true,
         isConst: json['const'] == true,
         isFactory: json['factory'] == true,
         isExternal: json['external'] == true);
   }

   ClosureInfo parseClosure(Map json) {
     ClosureInfo result = parseId(json['id']);
     return result
       ..name = json['name']
       ..parent = parseId(json['parent'])
       ..outputUnit = parseId(json['outputUnit'])
       ..size = json['size']
       ..function = parseId(json['function']);
   }

   Info parseId(id) {
     String serializedId = id;
     if (serializedId == null) {
       return null;
     }
     return registry.putIfAbsent(serializedId, () {
       if (serializedId.startsWith('function/')) {
         return new FunctionInfo.internal();
       } else if (serializedId.startsWith('closure/')) {
         return new ClosureInfo.internal();
       } else if (serializedId.startsWith('library/')) {
         return new LibraryInfo.internal();
       } else if (serializedId.startsWith('class/')) {
         return new ClassInfo.internal();
       } else if (serializedId.startsWith('field/')) {
         return new FieldInfo.internal();
       } else if (serializedId.startsWith('constant/')) {
         return new ConstantInfo.internal();
       } else if (serializedId.startsWith('typedef/')) {
         return new TypedefInfo.internal();
       } else if (serializedId.startsWith('outputUnit/')) {
         return new OutputUnitInfo.internal();
       }
       assert(false);
     });
   }

   List<CodeSpan> parseCode(dynamic json) {
     // backwards compatibility with format 5.1:
     if (json is String) {
       return [new CodeSpan(start: null, end: null, text: json)];
     }

     if (json is List) {
       return json.map((dynamic value) {
         Map<String, dynamic> jsonCode = value;
         return new CodeSpan(
             start: jsonCode['start'],
             end: jsonCode['end'],
             text: jsonCode['text']);
       }).toList();
     }

     return [];
   }
 }

 class AllInfoToJsonConverter extends Converter<AllInfo, Map>
     implements InfoVisitor<Map> {
   /// Whether to generate json compatible with format 5.1
   final bool isBackwardCompatible;
   final Map<Info, Id> ids = new HashMap<Info, Id>();
   final Set<int> usedIds = new Set<int>();

   AllInfoToJsonConverter({this.isBackwardCompatible: false});

   Id idFor(Info info) {
     var serializedId = ids[info];
     if (serializedId != null) return serializedId;

     assert(
         info is LibraryInfo ||
             info is ConstantInfo ||
             info is OutputUnitInfo ||
             info.parent != null,
         "$info");

     int id;
     if (info is ConstantInfo) {
       // No name and no parent, so `longName` isn't helpful
       assert(info.name == null);
       assert(info.parent == null);
       assert(info.code != null);
       // Instead, use the content of the code.
       id = info.code.first.text.hashCode;
     } else {
       id = longName(info, useLibraryUri: true, forId: true).hashCode;
     }

     while (!usedIds.add(id)) {
       id++;
     }
     serializedId = new Id(info.kind, '$id');
     return ids[info] = serializedId;
   }

   Map convert(AllInfo info) => info.accept(this);

   Map _visitList(List<Info> infos) {
     // Using SplayTree to maintain a consistent order of keys
     var map = new SplayTreeMap<String, Map>(compareNatural);
     for (var info in infos) {
       map['${idFor(info).id}'] = info.accept(this);
     }
     return map;
   }

   Map _visitAllInfoElements(AllInfo info) {
     var jsonLibraries = _visitList(info.libraries);
     var jsonClasses = _visitList(info.classes);
     var jsonFunctions = _visitList(info.functions);
     var jsonTypedefs = _visitList(info.typedefs);
     var jsonFields = _visitList(info.fields);
     var jsonConstants = _visitList(info.constants);
     var jsonClosures = _visitList(info.closures);
     return {
       'library': jsonLibraries,
       'class': jsonClasses,
       'function': jsonFunctions,
       'typedef': jsonTypedefs,
       'field': jsonFields,
       'constant': jsonConstants,
       'closure': jsonClosures,
     };
   }

   Map _visitDependencyInfo(DependencyInfo info) =>
       {'id': idFor(info.target).serializedId, 'mask': info.mask};

   Map _visitAllInfoHolding(AllInfo allInfo) {
     var map = new SplayTreeMap<String, List>(compareNatural);
     void helper(CodeInfo info) {
       if (info.uses.isEmpty) return;
       map[idFor(info).serializedId] = info.uses
           .map(_visitDependencyInfo)
           .toList()
             ..sort((a, b) => a['id'].compareTo(b['id']));
     }

     allInfo.functions.forEach(helper);
     allInfo.fields.forEach(helper);
     return map;
   }

   Map _visitAllInfoDependencies(AllInfo allInfo) {
     var map = new SplayTreeMap<String, List>(compareNatural);
     allInfo.dependencies.forEach((k, v) {
       map[idFor(k).serializedId] = _toSortedSerializedIds(v, idFor);
     });
     return map;
   }

   Map visitAll(AllInfo info) {
     var elements = _visitAllInfoElements(info);
     var jsonHolding = _visitAllInfoHolding(info);
     var jsonDependencies = _visitAllInfoDependencies(info);
     return {
       'elements': elements,
       'holding': jsonHolding,
       'dependencies': jsonDependencies,
       'outputUnits': info.outputUnits.map((u) => u.accept(this)).toList(),
       'dump_version': isBackwardCompatible ? 5 : info.version,
       'deferredFiles': info.deferredFiles,
       'dump_minor_version': isBackwardCompatible ? 1 : info.minorVersion,
       'program': info.program.accept(this)
     };
   }

   Map visitProgram(ProgramInfo info) {
     return {
       'entrypoint': idFor(info.entrypoint).serializedId,
       'size': info.size,
       'dart2jsVersion': info.dart2jsVersion,
       'compilationMoment': '${info.compilationMoment}',
       'compilationDuration': info.compilationDuration.inMicroseconds,
       'toJsonDuration': info.toJsonDuration.inMicroseconds,
       'dumpInfoDuration': info.dumpInfoDuration.inMicroseconds,
       'noSuchMethodEnabled': info.noSuchMethodEnabled,
       'isRuntimeTypeUsed': info.isRuntimeTypeUsed,
       'isIsolateInUse': info.isIsolateInUse,
       'isFunctionApplyUsed': info.isFunctionApplyUsed,
       'isMirrorsUsed': info.isMirrorsUsed,
       'minified': info.minified,
     };
   }

   Map _visitBasicInfo(BasicInfo info) {
     var res = {
       'id': idFor(info).serializedId,
       'kind': kindToString(info.kind),
       'name': info.name,
       'size': info.size,
     };
     // TODO(sigmund): Omit this also when outputUnit.id == 0 (most code is in
     // the main output unit by default).
     if (info.outputUnit != null) {
       res['outputUnit'] = idFor(info.outputUnit).serializedId;
     }
     if (info.coverageId != null) res['coverageId'] = info.coverageId;
     if (info.parent != null) res['parent'] = idFor(info.parent).serializedId;
     return res;
   }

   Map visitLibrary(LibraryInfo info) {
     return _visitBasicInfo(info)
       ..addAll(<String, Object>{
         'children': _toSortedSerializedIds(
             [
               info.topLevelFunctions,
               info.topLevelVariables,
               info.classes,
               info.typedefs
             ].expand((i) => i),
             idFor),
         'canonicalUri': '${info.uri}',
       });
   }

   Map visitClass(ClassInfo info) {
     return _visitBasicInfo(info)
       ..addAll(<String, Object>{
         // TODO(sigmund): change format, include only when abstract is true.
         'modifiers': {'abstract': info.isAbstract},
         'children': _toSortedSerializedIds(
             [info.fields, info.functions].expand((i) => i), idFor)
       });
   }

   Map visitField(FieldInfo info) {
     var result = _visitBasicInfo(info)
       ..addAll(<String, Object>{
         'children': _toSortedSerializedIds(info.closures, idFor),
         'inferredType': info.inferredType,
         'code': _serializeCode(info.code),
         'type': info.type,
       });
     if (info.isConst) {
       result['const'] = true;
       if (info.initializer != null) {
         result['initializer'] = idFor(info.initializer).serializedId;
       }
     }
     return result;
   }

   Map visitConstant(ConstantInfo info) => _visitBasicInfo(info)
     ..addAll(<String, Object>{'code': _serializeCode(info.code)});

   // TODO(sigmund): exclude false values (requires bumping the format version):
   //     var res = <String, bool>{};
   //     if (isStatic) res['static'] = true;
   //     if (isConst) res['const'] = true;
   //     if (isFactory) res['factory'] = true;
   //     if (isExternal) res['external'] = true;
   //     return res;
   Map _visitFunctionModifiers(FunctionModifiers mods) => {
         'static': mods.isStatic,
         'const': mods.isConst,
         'factory': mods.isFactory,
         'external': mods.isExternal,
       };

   Map _visitParameterInfo(ParameterInfo info) =>
       {'name': info.name, 'type': info.type, 'declaredType': info.declaredType};

   Map visitFunction(FunctionInfo info) {
     return _visitBasicInfo(info)
       ..addAll(<String, Object>{
         'children': _toSortedSerializedIds(info.closures, idFor),
         'modifiers': _visitFunctionModifiers(info.modifiers),
         'returnType': info.returnType,
         'inferredReturnType': info.inferredReturnType,
         'parameters':
             info.parameters.map((p) => _visitParameterInfo(p)).toList(),
         'sideEffects': info.sideEffects,
         'inlinedCount': info.inlinedCount,
         'code': _serializeCode(info.code),
         'type': info.type,
         // Note: version 3.2 of dump-info serializes `uses` in a section called
         // `holding` at the top-level.
       });
   }

   Map visitClosure(ClosureInfo info) {
     return _visitBasicInfo(info)
       ..addAll(<String, Object>{'function': idFor(info.function).serializedId});
   }

   visitTypedef(TypedefInfo info) => _visitBasicInfo(info)..['type'] = info.type;

   visitOutput(OutputUnitInfo info) => _visitBasicInfo(info)
     ..['filename'] = info.filename
     ..['imports'] = info.imports;

   Object _serializeCode(List<CodeSpan> code) {
     if (isBackwardCompatible) {
       return code.map((c) => c.text).join('\n');
     }
     return code
         .map<Object>((c) => {
               'start': c.start,
               'end': c.end,
               'text': c.text,
             })
         .toList();
   }
 }

 class AllInfoJsonCodec extends Codec<AllInfo, Map> {
   final Converter<AllInfo, Map> encoder;
   final Converter<Map, AllInfo> decoder = new JsonToAllInfoConverter();

   AllInfoJsonCodec({bool isBackwardCompatible: false})
       : encoder = new AllInfoToJsonConverter(
             isBackwardCompatible: isBackwardCompatible);
 }

 class Id {
   final InfoKind kind;
   final String id;

   Id(this.kind, this.id);

   String get serializedId => '${kindToString(kind)}/$id';
 }
	// 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.

	/// Converters and codecs for converting between JSON and [Info] classes.

	import 'dart:collection';
	import 'dart:convert';

	import 'package:collection/collection.dart';
	import 'src/util.dart';
	import 'info.dart';

	List<String> _toSortedSerializedIds(
	Iterable<Info> infos, Id Function(Info) getId) =>
	infos.map((i) => getId(i).serializedId).toList()..sort(compareNatural);

	// TODO(sigmund): add unit tests.
	class JsonToAllInfoConverter extends Converter<Map<String, dynamic>, AllInfo> {
	// Using `MashMap` here because it's faster than the default `LinkedHashMap`.
	final Map<String, Info> registry = new HashMap<String, Info>();

	AllInfo convert(Map<String, dynamic> json) {
	registry.clear();

	var result = new AllInfo();
	var elements = json['elements'];
	// TODO(srawlins): Since only the Map values are being extracted below,
	// replace `as` with `cast` when `cast` becomes available in Dart 2.0:
	//
	// .addAll(elements['library'].values.cast<Map>().map(parseLibrary));
	result.libraries.addAll(
	(elements['library'] as Map).values.map((l) => parseLibrary(l)));
	result.classes
	.addAll((elements['class'] as Map).values.map((c) => parseClass(c)));
	result.functions.addAll(
	(elements['function'] as Map).values.map((f) => parseFunction(f)));

	// TODO(het): Revert this when the dart2js with the new codec is in stable
	if (elements['closure'] != null) {
	result.closures.addAll(
	(elements['closure'] as Map).values.map((c) => parseClosure(c)));
	}
	result.fields
	.addAll((elements['field'] as Map).values.map((f) => parseField(f)));
	result.typedefs.addAll(
	(elements['typedef'] as Map).values.map((t) => parseTypedef(t)));
	result.constants.addAll(
	(elements['constant'] as Map).values.map((c) => parseConstant(c)));

	json['holding'].forEach((k, deps) {
	CodeInfo src = registry[k];
	assert(src != null);
	for (var dep in deps) {
	var target = registry[dep['id']];
	assert(target != null);
	src.uses.add(new DependencyInfo(target, dep['mask']));
	}
	});

	json['dependencies']?.forEach((String k, dependencies) {
	List<String> deps = dependencies;
	result.dependencies[registry[k]] = deps.map((d) => registry[d]).toList();
	});

	result.outputUnits
	.addAll((json['outputUnits'] as List).map((o) => parseOutputUnit(o)));

	result.program = parseProgram(json['program']);

	if (json['deferredFiles'] != null) {
	final deferredFilesMap =
	(json['deferredFiles'] as Map).cast<String, Map<String, dynamic>>();
	for (final library in deferredFilesMap.values) {
	if (library['imports'] != null) {
	// The importMap needs to be typed as <String, List<String>>, but the
	// json parser produces <String, dynamic>.
	final importMap = library['imports'] as Map<String, dynamic>;
	importMap.forEach((prefix, files) {
	importMap[prefix] = (files as List<dynamic>).cast<String>();
	});
	library['imports'] = importMap.cast<String, List<String>>();
	}
	}
	result.deferredFiles = deferredFilesMap;
	}

	// todo: version, etc
	return result;
	}

	OutputUnitInfo parseOutputUnit(Map json) {
	OutputUnitInfo result = parseId(json['id']);
	result
	..filename = json['filename']
	..name = json['name']
	..size = json['size'];
	result.imports
	.addAll((json['imports'] as List).map((s) => s as String) ?? const []);
	return result;
	}

	LibraryInfo parseLibrary(Map json) {
	LibraryInfo result = parseId(json['id']);
	result
	..name = json['name']
	..uri = Uri.parse(json['canonicalUri'])
	..outputUnit = parseId(json['outputUnit'])
	..size = json['size'];
	for (var child in json['children'].map(parseId)) {
	if (child is FunctionInfo) {
	result.topLevelFunctions.add(child);
	} else if (child is FieldInfo) {
	result.topLevelVariables.add(child);
	} else if (child is ClassInfo) {
	result.classes.add(child);
	} else {
	assert(child is TypedefInfo);
	result.typedefs.add(child);
	}
	}
	return result;
	}

	ClassInfo parseClass(Map json) {
	ClassInfo result = parseId(json['id']);
	result
	..name = json['name']
	..parent = parseId(json['parent'])
	..outputUnit = parseId(json['outputUnit'])
	..size = json['size']
	..isAbstract = json['modifiers']['abstract'] == true;
	assert(result is ClassInfo);
	for (var child in json['children'].map(parseId)) {
	if (child is FunctionInfo) {
	result.functions.add(child);
	} else {
	assert(child is FieldInfo);
	result.fields.add(child);
	}
	}
	return result;
	}

	FieldInfo parseField(Map json) {
	FieldInfo result = parseId(json['id']);
	return result
	..name = json['name']
	..parent = parseId(json['parent'])
	..coverageId = json['coverageId']
	..outputUnit = parseId(json['outputUnit'])
	..size = json['size']
	..type = json['type']
	..inferredType = json['inferredType']
	..code = parseCode(json['code'])
	..isConst = json['const'] ?? false
	..initializer = parseId(json['initializer'])
	..closures = (json['children'] as List)
	.map<ClosureInfo>((c) => parseId(c))
	.toList();
	}

	ConstantInfo parseConstant(Map json) {
	ConstantInfo result = parseId(json['id']);
	return result
	..code = parseCode(json['code'])
	..size = json['size']
	..outputUnit = parseId(json['outputUnit']);
	}

	TypedefInfo parseTypedef(Map json) {
	TypedefInfo result = parseId(json['id']);
	return result
	..name = json['name']
	..parent = parseId(json['parent'])
	..type = json['type']
	..size = 0;
	}

	ProgramInfo parseProgram(Map json) {
	var programInfo = new ProgramInfo()
	..entrypoint = parseId(json['entrypoint'])
	..size = json['size']
	..compilationMoment = DateTime.parse(json['compilationMoment'])
	..dart2jsVersion = json['dart2jsVersion']
	..noSuchMethodEnabled = json['noSuchMethodEnabled']
	..isRuntimeTypeUsed = json['isRuntimeTypeUsed']
	..isIsolateInUse = json['isIsolateInUse']
	..isFunctionApplyUsed = json['isFunctionApplyUsed']
	..isMirrorsUsed = json['isMirrorsUsed']
	..minified = json['minified'];

	// TODO(het): Revert this when the dart2js with the new codec is in stable
	var compilationDuration = json['compilationDuration'];
	if (compilationDuration is String) {
	programInfo.compilationDuration = _parseDuration(compilationDuration);
	} else {
	assert(compilationDuration is int);
	programInfo.compilationDuration =
	new Duration(microseconds: compilationDuration);
	}

	var toJsonDuration = json['toJsonDuration'];
	if (toJsonDuration is String) {
	programInfo.toJsonDuration = _parseDuration(toJsonDuration);
	} else {
	assert(toJsonDuration is int);
	programInfo.toJsonDuration = new Duration(microseconds: toJsonDuration);
	}

	var dumpInfoDuration = json['dumpInfoDuration'];
	if (dumpInfoDuration is String) {
	programInfo.dumpInfoDuration = _parseDuration(dumpInfoDuration);
	} else {
	assert(dumpInfoDuration is int);
	programInfo.dumpInfoDuration =
	new Duration(microseconds: dumpInfoDuration);
	}

	return programInfo;
	}

	/// Parse a string formatted as "XX:YY:ZZ.ZZZZZ" into a [Duration].
	Duration _parseDuration(String duration) {
	if (!duration.contains(':')) {
	return new Duration(milliseconds: int.parse(duration));
	}
	var parts = duration.split(':');
	var hours = double.parse(parts[0]);
	var minutes = double.parse(parts[1]);
	var seconds = double.parse(parts[2]);
	const secondsInMillis = 1000;
	const minutesInMillis = 60 * secondsInMillis;
	const hoursInMillis = 60 * minutesInMillis;
	var totalMillis = secondsInMillis * seconds +
	minutesInMillis * minutes +
	hoursInMillis * hours;
	return new Duration(milliseconds: totalMillis.round());
	}

	FunctionInfo parseFunction(Map json) {
	FunctionInfo result = parseId(json['id']);
	return result
	..name = json['name']
	..parent = parseId(json['parent'])
	..coverageId = json['coverageId']
	..outputUnit = parseId(json['outputUnit'])
	..size = json['size']
	..type = json['type']
	..returnType = json['returnType']
	..inferredReturnType = json['inferredReturnType']
	..parameters =
	(json['parameters'] as List).map((p) => parseParameter(p)).toList()
	..code = parseCode(json['code'])
	..sideEffects = json['sideEffects']
	..inlinedCount = json['inlinedCount']
	..modifiers =
	parseModifiers(new Map<String, bool>.from(json['modifiers']))
	..closures = (json['children'] as List)
	.map<ClosureInfo>((c) => parseId(c))
	.toList();
	}

	ParameterInfo parseParameter(Map json) =>
	new ParameterInfo(json['name'], json['type'], json['declaredType']);

	FunctionModifiers parseModifiers(Map<String, bool> json) {
	return new FunctionModifiers(
	isStatic: json['static'] == true,
	isConst: json['const'] == true,
	isFactory: json['factory'] == true,
	isExternal: json['external'] == true);
	}

	ClosureInfo parseClosure(Map json) {
	ClosureInfo result = parseId(json['id']);
	return result
	..name = json['name']
	..parent = parseId(json['parent'])
	..outputUnit = parseId(json['outputUnit'])
	..size = json['size']
	..function = parseId(json['function']);
	}

	Info parseId(id) {
	String serializedId = id;
	if (serializedId == null) {
	return null;
	}
	return registry.putIfAbsent(serializedId, () {
	if (serializedId.startsWith('function/')) {
	return new FunctionInfo.internal();
	} else if (serializedId.startsWith('closure/')) {
	return new ClosureInfo.internal();
	} else if (serializedId.startsWith('library/')) {
	return new LibraryInfo.internal();
	} else if (serializedId.startsWith('class/')) {
	return new ClassInfo.internal();
	} else if (serializedId.startsWith('field/')) {
	return new FieldInfo.internal();
	} else if (serializedId.startsWith('constant/')) {
	return new ConstantInfo.internal();
	} else if (serializedId.startsWith('typedef/')) {
	return new TypedefInfo.internal();
	} else if (serializedId.startsWith('outputUnit/')) {
	return new OutputUnitInfo.internal();
	}
	assert(false);
	});
	}

	List<CodeSpan> parseCode(dynamic json) {
	// backwards compatibility with format 5.1:
	if (json is String) {
	return [new CodeSpan(start: null, end: null, text: json)];
	}

	if (json is List) {
	return json.map((dynamic value) {
	Map<String, dynamic> jsonCode = value;
	return new CodeSpan(
	start: jsonCode['start'],
	end: jsonCode['end'],
	text: jsonCode['text']);
	}).toList();
	}

	return [];
	}
	}

	class AllInfoToJsonConverter extends Converter<AllInfo, Map>
	implements InfoVisitor<Map> {
	/// Whether to generate json compatible with format 5.1
	final bool isBackwardCompatible;
	final Map<Info, Id> ids = new HashMap<Info, Id>();
	final Set<int> usedIds = new Set<int>();

	AllInfoToJsonConverter({this.isBackwardCompatible: false});

	Id idFor(Info info) {
	var serializedId = ids[info];
	if (serializedId != null) return serializedId;

	assert(
	info is LibraryInfo \|\|
	info is ConstantInfo \|\|
	info is OutputUnitInfo \|\|
	info.parent != null,
	"$info");

	int id;
	if (info is ConstantInfo) {
	// No name and no parent, so `longName` isn't helpful
	assert(info.name == null);
	assert(info.parent == null);
	assert(info.code != null);
	// Instead, use the content of the code.
	id = info.code.first.text.hashCode;
	} else {
	id = longName(info, useLibraryUri: true, forId: true).hashCode;
	}

	while (!usedIds.add(id)) {
	id++;
	}
	serializedId = new Id(info.kind, '$id');
	return ids[info] = serializedId;
	}

	Map convert(AllInfo info) => info.accept(this);

	Map _visitList(List<Info> infos) {
	// Using SplayTree to maintain a consistent order of keys
	var map = new SplayTreeMap<String, Map>(compareNatural);
	for (var info in infos) {
	map['${idFor(info).id}'] = info.accept(this);
	}
	return map;
	}

	Map _visitAllInfoElements(AllInfo info) {
	var jsonLibraries = _visitList(info.libraries);
	var jsonClasses = _visitList(info.classes);
	var jsonFunctions = _visitList(info.functions);
	var jsonTypedefs = _visitList(info.typedefs);
	var jsonFields = _visitList(info.fields);
	var jsonConstants = _visitList(info.constants);
	var jsonClosures = _visitList(info.closures);
	return {
	'library': jsonLibraries,
	'class': jsonClasses,
	'function': jsonFunctions,
	'typedef': jsonTypedefs,
	'field': jsonFields,
	'constant': jsonConstants,
	'closure': jsonClosures,
	};
	}

	Map _visitDependencyInfo(DependencyInfo info) =>
	{'id': idFor(info.target).serializedId, 'mask': info.mask};

	Map _visitAllInfoHolding(AllInfo allInfo) {
	var map = new SplayTreeMap<String, List>(compareNatural);
	void helper(CodeInfo info) {
	if (info.uses.isEmpty) return;
	map[idFor(info).serializedId] = info.uses
	.map(_visitDependencyInfo)
	.toList()
	..sort((a, b) => a['id'].compareTo(b['id']));
	}

	allInfo.functions.forEach(helper);
	allInfo.fields.forEach(helper);
	return map;
	}

	Map _visitAllInfoDependencies(AllInfo allInfo) {
	var map = new SplayTreeMap<String, List>(compareNatural);
	allInfo.dependencies.forEach((k, v) {
	map[idFor(k).serializedId] = _toSortedSerializedIds(v, idFor);
	});
	return map;
	}

	Map visitAll(AllInfo info) {
	var elements = _visitAllInfoElements(info);
	var jsonHolding = _visitAllInfoHolding(info);
	var jsonDependencies = _visitAllInfoDependencies(info);
	return {
	'elements': elements,
	'holding': jsonHolding,
	'dependencies': jsonDependencies,
	'outputUnits': info.outputUnits.map((u) => u.accept(this)).toList(),
	'dump_version': isBackwardCompatible ? 5 : info.version,
	'deferredFiles': info.deferredFiles,
	'dump_minor_version': isBackwardCompatible ? 1 : info.minorVersion,
	'program': info.program.accept(this)
	};
	}

	Map visitProgram(ProgramInfo info) {
	return {
	'entrypoint': idFor(info.entrypoint).serializedId,
	'size': info.size,
	'dart2jsVersion': info.dart2jsVersion,
	'compilationMoment': '${info.compilationMoment}',
	'compilationDuration': info.compilationDuration.inMicroseconds,
	'toJsonDuration': info.toJsonDuration.inMicroseconds,
	'dumpInfoDuration': info.dumpInfoDuration.inMicroseconds,
	'noSuchMethodEnabled': info.noSuchMethodEnabled,
	'isRuntimeTypeUsed': info.isRuntimeTypeUsed,
	'isIsolateInUse': info.isIsolateInUse,
	'isFunctionApplyUsed': info.isFunctionApplyUsed,
	'isMirrorsUsed': info.isMirrorsUsed,
	'minified': info.minified,
	};
	}

	Map _visitBasicInfo(BasicInfo info) {
	var res = {
	'id': idFor(info).serializedId,
	'kind': kindToString(info.kind),
	'name': info.name,
	'size': info.size,
	};
	// TODO(sigmund): Omit this also when outputUnit.id == 0 (most code is in
	// the main output unit by default).
	if (info.outputUnit != null) {
	res['outputUnit'] = idFor(info.outputUnit).serializedId;
	}
	if (info.coverageId != null) res['coverageId'] = info.coverageId;
	if (info.parent != null) res['parent'] = idFor(info.parent).serializedId;
	return res;
	}

	Map visitLibrary(LibraryInfo info) {
	return _visitBasicInfo(info)
	..addAll(<String, Object>{
	'children': _toSortedSerializedIds(
	[
	info.topLevelFunctions,
	info.topLevelVariables,
	info.classes,
	info.typedefs
	].expand((i) => i),
	idFor),
	'canonicalUri': '${info.uri}',
	});
	}

	Map visitClass(ClassInfo info) {
	return _visitBasicInfo(info)
	..addAll(<String, Object>{
	// TODO(sigmund): change format, include only when abstract is true.
	'modifiers': {'abstract': info.isAbstract},
	'children': _toSortedSerializedIds(
	[info.fields, info.functions].expand((i) => i), idFor)
	});
	}

	Map visitField(FieldInfo info) {
	var result = _visitBasicInfo(info)
	..addAll(<String, Object>{
	'children': _toSortedSerializedIds(info.closures, idFor),
	'inferredType': info.inferredType,
	'code': _serializeCode(info.code),
	'type': info.type,
	});
	if (info.isConst) {
	result['const'] = true;
	if (info.initializer != null) {
	result['initializer'] = idFor(info.initializer).serializedId;
	}
	}
	return result;
	}

	Map visitConstant(ConstantInfo info) => _visitBasicInfo(info)
	..addAll(<String, Object>{'code': _serializeCode(info.code)});

	// TODO(sigmund): exclude false values (requires bumping the format version):
	// var res = <String, bool>{};
	// if (isStatic) res['static'] = true;
	// if (isConst) res['const'] = true;
	// if (isFactory) res['factory'] = true;
	// if (isExternal) res['external'] = true;
	// return res;
	Map _visitFunctionModifiers(FunctionModifiers mods) => {
	'static': mods.isStatic,
	'const': mods.isConst,
	'factory': mods.isFactory,
	'external': mods.isExternal,
	};

	Map _visitParameterInfo(ParameterInfo info) =>
	{'name': info.name, 'type': info.type, 'declaredType': info.declaredType};

	Map visitFunction(FunctionInfo info) {
	return _visitBasicInfo(info)
	..addAll(<String, Object>{
	'children': _toSortedSerializedIds(info.closures, idFor),
	'modifiers': _visitFunctionModifiers(info.modifiers),
	'returnType': info.returnType,
	'inferredReturnType': info.inferredReturnType,
	'parameters':
	info.parameters.map((p) => _visitParameterInfo(p)).toList(),
	'sideEffects': info.sideEffects,
	'inlinedCount': info.inlinedCount,
	'code': _serializeCode(info.code),
	'type': info.type,
	// Note: version 3.2 of dump-info serializes `uses` in a section called
	// `holding` at the top-level.
	});
	}

	Map visitClosure(ClosureInfo info) {
	return _visitBasicInfo(info)
	..addAll(<String, Object>{'function': idFor(info.function).serializedId});
	}

	visitTypedef(TypedefInfo info) => _visitBasicInfo(info)..['type'] = info.type;

	visitOutput(OutputUnitInfo info) => _visitBasicInfo(info)
	..['filename'] = info.filename
	..['imports'] = info.imports;

	Object _serializeCode(List<CodeSpan> code) {
	if (isBackwardCompatible) {
	return code.map((c) => c.text).join('\n');
	}
	return code
	.map<Object>((c) => {
	'start': c.start,
	'end': c.end,
	'text': c.text,
	})
	.toList();
	}
	}

	class AllInfoJsonCodec extends Codec<AllInfo, Map> {
	final Converter<AllInfo, Map> encoder;
	final Converter<Map, AllInfo> decoder = new JsonToAllInfoConverter();

	AllInfoJsonCodec({bool isBackwardCompatible: false})
	: encoder = new AllInfoToJsonConverter(
	isBackwardCompatible: isBackwardCompatible);
	}

	class Id {
	final InfoKind kind;
	final String id;

	Id(this.kind, this.id);

	String get serializedId => '${kindToString(kind)}/$id';
	}