- Base JSON stream printing on stack objects.

runtime/vm/json_stream.h

Index: runtime/vm/json_stream.h
===================================================================
--- runtime/vm/json_stream.h	(revision 27342)
+++ runtime/vm/json_stream.h	(working copy)
@@ -6,16 +6,38 @@
 #define VM_JSON_STREAM_H_
 
 #include "platform/json.h"
+#include "vm/allocation.h"
 
 namespace dart {
 
 class Object;
+class JSONObject;
+class JSONArray;
 
 class JSONStream : ValueObject {
  public:
-  explicit JSONStream(TextBuffer* buffer);
+  explicit JSONStream(intptr_t buf_size = 256);
   ~JSONStream();
 
+  const char* ToCString() { return buffer_.buf(); }
+
+  void SetArguments(const char** arguments, intptr_t num_arguments);
+  void SetOptions(const char** option_keys, const char** option_values,
+                  intptr_t num_options);
+
+  intptr_t num_arguments() const { return num_arguments_; }
+  const char* GetArgument(intptr_t i) const {
+    return arguments_[i];
+  }
+  intptr_t num_options() const { return num_options_; }
+  const char* GetOptionKey(intptr_t i) const {
+    return option_keys_[i];
+  }
+  const char* GetOptionValue(intptr_t i) const {
+    return option_values_[i];
+  }
+
+ private:
   void Clear();
 
   void OpenObject(const char* property_name = NULL);
@@ -36,38 +58,94 @@
   void PrintProperty(const char* name, double d);
   void PrintProperty(const char* name, const char* s);
   void PrintfProperty(const char* name, const char* format, ...)
-      PRINTF_ATTRIBUTE(3, 4);
+  PRINTF_ATTRIBUTE(3, 4);
   void PrintProperty(const char* name, const Object& o, bool ref = true);
 
-  void SetArguments(const char** arguments, intptr_t num_arguments);
-  void SetOptions(const char** option_keys, const char** option_values,
-                  intptr_t num_options);
-
-  intptr_t num_arguments() const { return num_arguments_; }
-  const char* GetArgument(intptr_t i) const {
-    return arguments_[i];
-  }
-  intptr_t num_options() const { return num_options_; }
-  const char* GetOptionKey(intptr_t i) const {
-    return option_keys_[i];
-  }
-  const char* GetOptionValue(intptr_t i) const {
-    return option_values_[i];
-  }
-
- private:
   void PrintPropertyName(const char* name);
   void PrintCommaIfNeeded();
   bool NeedComma();
+
+  intptr_t nesting_level() const { return open_objects_; }
+
   intptr_t open_objects_;
-  TextBuffer* buffer_;
+  TextBuffer buffer_;
   const char** arguments_;
   intptr_t num_arguments_;
   const char** option_keys_;
   const char** option_values_;
   intptr_t num_options_;
+
+  friend class JSONObject;
+  friend class JSONArray;
 };
 
+
+class JSONObject : public ValueObject {
+ public:
+  explicit JSONObject(JSONStream* stream) : stream_(stream) {
+    stream_->OpenObject();
+  }
+  JSONObject(const JSONObject& obj, const char* name) : stream_(obj.stream_) {
+    stream_->OpenObject(name);
+  }
+  explicit JSONObject(const JSONArray& arr);
+
+  ~JSONObject() {
+    stream_->CloseObject();
+  }
+
+  void AddProperty(const char* name, bool b) const {
+    stream_->PrintPropertyBool(name, b);
+  }
+  void AddProperty(const char* name, intptr_t i) const {
+    stream_->PrintProperty(name, i);
+  }
+  void AddProperty(const char* name, double d) const {
+    stream_->PrintProperty(name, d);
+  }
+  void AddProperty(const char* name, const Object& obj, bool ref = true) const {
+    stream_->PrintProperty(name, obj, ref);
+  }
+  void AddPropertyF(const char* name, const char* format, ...) const
+      PRINTF_ATTRIBUTE(3, 4);
+
+ private:
+  JSONStream* stream_;
+
+  friend class JSONArray;
+};
+
+
+class JSONArray : public ValueObject {
+ public:
+  explicit JSONArray(JSONStream* stream) : stream_(stream) {
+    stream_->OpenArray();
+  }
+  JSONArray(const JSONObject& obj, const char* name) : stream_(obj.stream_) {
+    stream_->OpenArray(name);
+  }
+  JSONArray(const JSONArray& arr) : stream_(arr.stream_) {
+    stream_->OpenArray();
+  }
+  ~JSONArray() {
+    stream_->CloseArray();
+  }
+
+  void AddValue(bool b) const { stream_->PrintValueBool(b); }
+  void AddValue(intptr_t i) const { stream_->PrintValue(i); }
+  void AddValue(double d) const { stream_->PrintValue(d); }
+  void AddValue(const char* s) const { stream_->PrintValue(s); }
+  void AddValue(const Object& obj, bool ref = true) const {
+    stream_->PrintValue(obj, ref);
+  }
+  void AddValueF(const char* format, ...) const PRINTF_ATTRIBUTE(2, 3);
+
+ private:
+  JSONStream* stream_;
+
+  friend class JSONObject;
+};
+
 }  // namespace dart
 
 #endif  // VM_JSON_STREAM_H_