Change how we provide value previews in the vm service.

runtime/vm/object.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 12693 matching lines @@
     const String& type_name = String::Handle(type.UserVisibleName());
     // Calculate the size of the string.
     intptr_t len = OS::SNPrint(NULL, 0, kFormat, type_name.ToCString()) + 1;
     char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
     OS::SNPrint(chars, len, kFormat, type_name.ToCString());
     return chars;
   }
 }
 
 
-const char* Instance::ToUserCString(intptr_t max_len, intptr_t nesting) const {
-  if (IsNull()) {
-    return "null";
-  } else if (raw() == Object::sentinel().raw()) {
-    return "<not initialized>";
-  } else if (raw() == Object::transition_sentinel().raw()) {
-    return "<being initialized>";
-  } else {
-    return ToCString();
-  }
-}
-
-
 void Instance::PrintSharedInstanceJSON(JSONObject* jsobj, bool ref) const {
   jsobj->AddProperty("type", JSONType(ref));
   Class& cls = Class::Handle(this->clazz());
   jsobj->AddProperty("class", cls);
+  // TODO(turnidge): Provide the type arguments here too.
   if (ref) {
     return;
   }
 
-  jsobj->AddProperty("size", raw()->Size());
+  if (raw()->IsHeapObject()) {
+    jsobj->AddProperty("size", raw()->Size());
+  }
 
   // Walk the superclass chain, adding all instance fields.
   {
     Instance& fieldValue = Instance::Handle();
     JSONArray jsarr(jsobj, "fields");
     while (!cls.IsNull()) {
       const Array& field_array = Array::Handle(cls.fields());
       Field& field = Field::Handle();
       if (!field_array.IsNull()) {
         for (intptr_t i = 0; i < field_array.Length(); i++) {
@@ skipping 22 matching lines @@
 }
 
 
 void Instance::PrintToJSONStream(JSONStream* stream, bool ref) const {
   JSONObject jsobj(stream);
 
   // Handle certain special instance values.
   if (IsNull()) {
     jsobj.AddProperty("type", ref ? "@Null" : "Null");
     jsobj.AddProperty("id", "objects/null");
-    jsobj.AddProperty("preview", "null");
+    jsobj.AddProperty("valueAsString", "null");
     return;
   } else if (raw() == Object::sentinel().raw()) {
     jsobj.AddProperty("type", ref ? "@Null" : "Null");
     jsobj.AddProperty("id", "objects/not-initialized");
-    jsobj.AddProperty("preview", "<not initialized>");
+    jsobj.AddProperty("valueAsString", "<not initialized>");
     return;
   } else if (raw() == Object::transition_sentinel().raw()) {
     jsobj.AddProperty("type", ref ? "@Null" : "Null");
     jsobj.AddProperty("id", "objects/being-initialized");
-    jsobj.AddProperty("preview", "<being initialized>");
-    return;
-  } else if (raw() == Symbols::OptimizedOut().raw()) {
-    // TODO(turnidge): This is a hack.  The user could have this
-    // special string in their program.  Fixing this involves updating
-    // the debugging api a bit.
-    jsobj.AddProperty("type", ref ? "@Null" : "Null");
-    jsobj.AddProperty("id", "objects/optimized-out");
-    jsobj.AddProperty("preview", "<optimized out>");
+    jsobj.AddProperty("valueAsString", "<being initialized>");
     return;
   }
 
   PrintSharedInstanceJSON(&jsobj, ref);
   ObjectIdRing* ring = Isolate::Current()->object_id_ring();
   const intptr_t id = ring->GetIdForObject(raw());
   if (IsClosure()) {
     const Function& closureFunc = Function::Handle(Closure::function(*this));
     jsobj.AddProperty("closureFunc", closureFunc);
   }
   jsobj.AddPropertyF("id", "objects/%" Pd "", id);
-  jsobj.AddProperty("preview", ToUserCString(40));
   if (ref) {
     return;
   }
 }
 
 
 bool AbstractType::IsResolved() const {
   // AbstractType is an abstract class.
   UNREACHABLE();
   return false;
@@ skipping 1697 matching lines @@
 
 
 const char* Number::ToCString() const {
   // Number is an interface. No instances of Number should exist.
   UNREACHABLE();
   return "Number";
 }
 
 
 void Number::PrintToJSONStream(JSONStream* stream, bool ref) const {
-  Instance::PrintToJSONStream(stream, ref);
+  JSONObject jsobj(stream);
+  PrintSharedInstanceJSON(&jsobj, ref);
+  ObjectIdRing* ring = Isolate::Current()->object_id_ring();
+  const intptr_t id = ring->GetIdForObject(raw());
+  jsobj.AddPropertyF("id", "objects/%" Pd "", id);
+  jsobj.AddProperty("valueAsString", ToCString());
 }
 
 
 const char* Integer::ToCString() const {
   // Integer is an interface. No instances of Integer should exist.
   UNREACHABLE();
   return "Integer";
 }
 
 
@@ skipping 421 matching lines @@
   // Calculate the size of the string.
   intptr_t len = OS::SNPrint(NULL, 0, kFormat, Value()) + 1;
   char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
   OS::SNPrint(chars, len, kFormat, Value());
   return chars;
 }
 
 
 void Smi::PrintToJSONStream(JSONStream* stream, bool ref) const {
   JSONObject jsobj(stream);
-  jsobj.AddProperty("type", JSONType(ref));
+  PrintSharedInstanceJSON(&jsobj, ref);
   jsobj.AddPropertyF("id", "objects/int-%" Pd "", Value());
-  class Class& cls = Class::Handle(this->clazz());
-  jsobj.AddProperty("class", cls);
-  jsobj.AddPropertyF("preview", "%" Pd "", Value());
+  jsobj.AddPropertyF("valueAsString", "%" Pd "", Value());
 }
 
 
 RawClass* Smi::Class() {
   return Isolate::Current()->object_store()->smi_class();
 }
 
 
 void Mint::set_value(int64_t value) const {
   raw_ptr()->value_ = value;
@@ skipping 1208 matching lines @@
     }
     if (len > too_long) {
       // No point going further.
       break;
     }
   }
   return len;
 }
 
 
-const char* String::ToUserCString(intptr_t max_len, intptr_t nesting) const {
+const char* String::ToUserCString(intptr_t max_len) const {
   // Compute the needed length for the buffer.
   const intptr_t escaped_len = EscapedStringLen(max_len);
   intptr_t print_len = escaped_len;
   intptr_t buffer_len = escaped_len + 2;  // +2 for quotes.
   if (buffer_len > max_len) {
     buffer_len = max_len;     // Truncate.
     print_len = max_len - 5;  // -2 for quotes, -3 for elipsis.
   }
 
   // Allocate the buffer.
@@ skipping 16 matching lines @@
     buffer[pos++] = '.';
   }
   ASSERT(pos <= buffer_len);
   buffer[pos++] = '\0';
 
   return buffer;
 }
 
 
 void String::PrintToJSONStream(JSONStream* stream, bool ref) const {
-  Instance::PrintToJSONStream(stream, ref);
+  JSONObject jsobj(stream);
+  if (raw() == Symbols::OptimizedOut().raw()) {
+    // TODO(turnidge): This is a hack.  The user could have this
+    // special string in their program.  Fixing this involves updating
+    // the debugging api a bit.
+    jsobj.AddProperty("type", ref ? "@Null" : "Null");
+    jsobj.AddProperty("id", "objects/optimized-out");
+    jsobj.AddProperty("valueAsString", "<optimized out>");
+    return;
+  }
+  PrintSharedInstanceJSON(&jsobj, ref);
+  ObjectIdRing* ring = Isolate::Current()->object_id_ring();
+  const intptr_t id = ring->GetIdForObject(raw());
+  jsobj.AddPropertyF("id", "objects/%" Pd "", id);
+  jsobj.AddProperty("valueAsString", ToUserCString(1024));
 }
 
 
 void String::ToUTF8(uint8_t* utf8_array, intptr_t array_len) const {
   ASSERT(array_len >= Utf8::Length(*this));
   Utf8::Encode(*this, reinterpret_cast<char*>(utf8_array), array_len);
 }
 
 
 static FinalizablePersistentHandle* AddFinalizer(
@@ skipping 777 matching lines @@
 }
 
 
 void Bool::PrintToJSONStream(JSONStream* stream, bool ref) const {
   const char* str = ToCString();
   JSONObject jsobj(stream);
   jsobj.AddProperty("type", JSONType(ref));
   jsobj.AddPropertyF("id", "objects/bool-%s", str);
   class Class& cls = Class::Handle(this->clazz());
   jsobj.AddProperty("class", cls);
-  jsobj.AddPropertyF("preview", "%s", str);
+  jsobj.AddPropertyF("valueAsString", "%s", str);
 }
 
 
 bool Array::Equals(const Instance& other) const {
   if (this->raw() == other.raw()) {
     // Both handles point to the same raw instance.
     return true;
   }
 
   // An Array may be compared to an ImmutableArray.
@@ skipping 298 matching lines @@
     return "_GrowableList NULL";
   }
   const char* format = "Instance(length:%" Pd ") of '_GrowableList'";
   intptr_t len = OS::SNPrint(NULL, 0, format, Length()) + 1;
   char* chars = Isolate::Current()->current_zone()->Alloc<char>(len);
   OS::SNPrint(chars, len, format, Length());
   return chars;
 }
 
 
-const char* GrowableObjectArray::ToUserCString(intptr_t max_len,
-                                               intptr_t nesting) const {
-  if (Length() == 0) {
-    return "[]";
-  }
-  if (nesting > 3) {
-    return "[...]";
-  }
-
-  Isolate* isolate = Isolate::Current();
-  Zone* zone = isolate->current_zone();
-  Object& obj = Object::Handle(isolate);
-  Instance& element = Instance::Handle(isolate);
-
-  // Pre-print the suffix that we will use if the string is truncated.
-  // It is important to know the suffix length when deciding where to
-  // limit the list.
-  const intptr_t kMaxTruncSuffixLen = 16;
-  char trunc_suffix[kMaxTruncSuffixLen];
-  intptr_t trunc_suffix_len;
-  if (nesting == 0) {
-    trunc_suffix_len = OS::SNPrint(trunc_suffix, 16, "...](length:%" Pd ")",
-                                   Length());
-  } else {
-    trunc_suffix_len = OS::SNPrint(trunc_suffix, 16, "...]");
-  }
-  bool truncate = false;
-
-  const int kMaxPrintElements = 128;
-  const char* strings[kMaxPrintElements];
-  intptr_t print_len = 1;  // +1 for "["
-
-  // Figure out how many elements will fit in the string.
-  int i = 0;
-  while (i < Length()) {
-    if (i == kMaxPrintElements) {
-      if (i < Length()) {
-        truncate = true;
-      }
-      break;
-    }
-    obj = At(i);
-    if (!obj.IsNull() && !obj.IsInstance()) {
-      UNREACHABLE();
-      return "[<invalid list>]";
-    }
-    element ^= obj.raw();
-
-    // Choose max child length.  This is chosen so that it is small
-    // enough to maybe fit but not so small that we can't print
-    // anything.
-    int child_max_len = max_len - print_len;
-    if ((i + 1) < Length()) {
-      child_max_len -= (trunc_suffix_len + 1);  // 1 for ","
-    } else {
-      child_max_len -= 1;  // 1 for "]"
-    }
-    if (child_max_len < 8) {
-      child_max_len = 8;
-    }
-
-    strings[i] = element.ToUserCString(child_max_len,  nesting + 1);
-    print_len += strlen(strings[i]) + 1;  // +1 for "," or "]"
-    i++;
-    if (print_len > max_len) {
-      truncate = true;
-      break;
-    }
-  }
-  if (truncate) {
-    // Go backwards until there is enough room for the truncation suffix.
-    while (i >= 0 && (print_len + trunc_suffix_len) > max_len) {
-      i--;
-      print_len -= (strlen(strings[i]) + 1);  // +1 for ","
-    }
-  }
-
-  // Finally, allocate and print the string.
-  int num_to_print = i;
-  char* buffer = zone->Alloc<char>(print_len + 1);  // +1 for "\0"
-  intptr_t pos = 0;
-  buffer[pos++] = '[';
-  for (i = 0; i < num_to_print; i++) {
-    if ((i + 1) == Length()) {
-      pos += OS::SNPrint((buffer + pos), (max_len + 1 - pos),
-                         "%s]", strings[i]);
-    } else {
-      pos += OS::SNPrint((buffer + pos), (max_len + 1 - pos),
-                         "%s,", strings[i]);
-    }
-  }
-  if (i < Length()) {
-    pos += OS::SNPrint((buffer + pos), (max_len + 1 - pos), "%s", trunc_suffix);
-  }
-  ASSERT(pos <= max_len);
-  buffer[pos] = '\0';
-  return buffer;
-}
-
-
 void GrowableObjectArray::PrintToJSONStream(JSONStream* stream,
                                             bool ref) const {
   JSONObject jsobj(stream);
   PrintSharedInstanceJSON(&jsobj, ref);
   ObjectIdRing* ring = Isolate::Current()->object_id_ring();
   const intptr_t id = ring->GetIdForObject(raw());
   jsobj.AddPropertyF("id", "objects/%" Pd "", id);
   jsobj.AddProperty("length", Length());
   if (ref) {
     return;
@@ skipping 860 matching lines @@
   return "_MirrorReference";
 }
 
 
 void MirrorReference::PrintToJSONStream(JSONStream* stream, bool ref) const {
   Instance::PrintToJSONStream(stream, ref);
 }
 
 
 }  // namespace dart