Support serialization of the compiler backbone.

pkg/compiler/lib/src/serialization/json_serializer.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 dart2js.serialization.json;
+
+import 'dart:convert';
+import 'keys.dart';
+import 'serialization.dart';
+import 'values.dart';
+
+/// Serialization encoder for JSON.
+class JsonSerializationEncoder implements SerializationEncoder {
+  const JsonSerializationEncoder();
+
+  String encode(ObjectValue objectValue) {
+    return new JsonEncoder.withIndent(' ').convert(
+        const JsonValueEncoder().convert(objectValue));
+  }
+}
+
+/// Serialization decoder for JSON.
+class JsonSerializationDecoder implements SerializationDecoder {
+  const JsonSerializationDecoder();
+
+  Map decode(String text) => JSON.decode(text);
+
+  /// Returns the name of the [key] which used for to store a [Key] into a
+  /// [Map]; corresponding to the encoding of object properties in
+  /// [JsonValueEncoder.visitObject].
+  getObjectPropertyValue(Key key) => key.name;
+}
+
+/// A [ValueVisitor] that computes a JSON object value.
+class JsonValueEncoder implements ValueVisitor {
+  const JsonValueEncoder();
+
+  convert(Value value) => visit(value, null);
+
+  @override
+  visit(Value value, [arg]) => value.accept(this, arg);
+
+  @override
+  bool visitBool(BoolValue value, arg) => value.value;
+
+  @override
+  visitConstant(ConstantValue value, arg) => visit(value.id);
+
+  @override
+  double visitDouble(DoubleValue value, arg) => value.value;
+
+  @override
+  visitElement(ElementValue value, arg) => visit(value.id);
+
+  @override
+  visitEnum(EnumValue value, arg) => value.value.index;
+
+  @override
+  int visitInt(IntValue value, arg) => value.value;
+
+  @override
+  List visitList(ListValue value, arg) => value.values.map(visit).toList();
+
+  @override
+  Map visitMap(MapValue value, arg) {
+    Map<String, dynamic> map = <String, dynamic>{};
+    value.map.forEach((String key, Value value) {
+      map[key] = visit(value);
+    });
+    return map;
+  }
+
+  @override
+  Map visitObject(ObjectValue value, arg) {
+    Map<String, dynamic> map = <String, dynamic>{};
+    value.map.forEach((Key key, Value value) {
+      map[key.name] = visit(value);
+    });
+    return map;
+  }
+
+  @override
+  String visitString(StringValue value, arg) => value.value;
+
+  @override
+  visitType(TypeValue value, arg) => visit(value.id);
+
+  @override
+  visitUri(UriValue value, arg) => '${value.value}';
+}
+
+/// [ValueVisitor] that generates a verbose JSON-like output.
+class PrettyPrintEncoder implements ValueVisitor {
+  StringBuffer buffer;
+
+  String toText(Value value) {
+    buffer = new StringBuffer();
+    visit(value, '');
+    String text = buffer.toString();
+    buffer = null;
+    return text;
+  }
+
+  @override
+  void visit(Value value, String indentation) {
+    value.accept(this, indentation);
+  }
+
+  @override
+  void visitBool(BoolValue value, String indentation) {
+    buffer.write(value.value);
+  }
+
+  @override
+  void visitConstant(ConstantValue value, String indentation) {
+    buffer.write('Constant(${value.id}):${value.constant.getText()}');
+  }
+
+  @override
+  void visitDouble(DoubleValue value, String indentation) {
+    buffer.write(value.value);
+  }
+  @override
+  void visitElement(ElementValue value, String indentation) {
+    buffer.write('Element(${value.id}):${value.element}');
+  }
+
+  @override
+  void visitEnum(EnumValue value, String indentation) {
+    buffer.write(value.value);
+  }
+
+  @override
+  void visitInt(IntValue value, String indentation) {
+    buffer.write(value.value);
+  }
+
+  @override
+  void visitList(ListValue value, String indentation) {
+    if (value.values.isEmpty) {
+      buffer.write('[]');
+    } else {
+      buffer.write('[');
+      bool needsComma = false;
+      String nextIndentation = '${indentation}  ';
+      for (Value element in value.values) {
+        if (needsComma) {
+          buffer.write(',');
+        }
+        buffer.write('\n$nextIndentation');
+        visit(element, nextIndentation);
+        needsComma = true;
+      }
+      buffer.write('\n$indentation]');
+    }
+  }
+
+  @override
+  void visitMap(MapValue value, String indentation) {
+    if (value.map.isEmpty) {
+      buffer.write('{}');
+    } else {
+      buffer.write('{');
+      bool needsComma = false;
+      String nextIndentation = '${indentation}  ';
+      value.map.forEach((String key, Value subvalue) {
+        if (needsComma) {
+          buffer.write(',');
+        }
+        buffer.write('\n$nextIndentation$key: ');
+        visit(subvalue, nextIndentation);
+        needsComma = true;
+      });
+      buffer.write('\n$indentation}');
+    }
+  }
+
+  @override
+  void visitObject(ObjectValue value, String indentation) {
+    if (value.map.isEmpty) {
+      buffer.write('{}');
+    } else {
+      buffer.write('{');
+      bool needsComma = false;
+      String nextIndentation = '${indentation}  ';
+      value.map.forEach((Key key, Value subvalue) {
+        if (needsComma) {
+          buffer.write(',');
+        }
+        buffer.write('\n$nextIndentation$key: ');
+        visit(subvalue, nextIndentation);
+        needsComma = true;
+      });
+      buffer.write('\n$indentation}');
+    }
+  }
+
+  @override
+  void visitString(StringValue value, String indentation) {
+    buffer.write('"${value.value}"');
+  }
+
+  @override
+  void visitType(TypeValue value, String indentation) {
+    buffer.write('Type(${value.id}):${value.type}');
+  }
+
+  @override
+  void visitUri(UriValue value, String indentation) {
+    buffer.write('Uri(${value.value})');
+  }
+}