Expose the content of Maps and WeakMaps through MapMirror.

src/mirror-debugger.js

 // Copyright 2006-2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Handle id counters.
 var next_handle_ = 0;
 var next_transient_handle_ = -1;
 
 // Mirror cache.
 var mirror_cache_ = [];
@@ skipping 63 matching lines @@
   } else if (IS_DATE(value)) {
     mirror = new DateMirror(value);
   } else if (IS_FUNCTION(value)) {
     mirror = new FunctionMirror(value);
   } else if (IS_REGEXP(value)) {
     mirror = new RegExpMirror(value);
   } else if (IS_ERROR(value)) {
     mirror = new ErrorMirror(value);
   } else if (IS_SCRIPT(value)) {
     mirror = new ScriptMirror(value);
+  } else if (IS_MAP(value) || IS_WEAKMAP(value)) {
+    mirror = new MapMirror(value);
   } else if (ObjectIsPromise(value)) {
     mirror = new PromiseMirror(value);
   } else {
     mirror = new ObjectMirror(value, OBJECT_TYPE, opt_transient);
   }
 
   if (mirror_cache_enabled_) mirror_cache_[mirror.handle()] = mirror;
   return mirror;
 }
 
@@ skipping 54 matching lines @@
 var FUNCTION_TYPE = 'function';
 var REGEXP_TYPE = 'regexp';
 var ERROR_TYPE = 'error';
 var PROPERTY_TYPE = 'property';
 var INTERNAL_PROPERTY_TYPE = 'internalProperty';
 var FRAME_TYPE = 'frame';
 var SCRIPT_TYPE = 'script';
 var CONTEXT_TYPE = 'context';
 var SCOPE_TYPE = 'scope';
 var PROMISE_TYPE = 'promise';
+var MAP_TYPE = 'map';
 
 // Maximum length when sending strings through the JSON protocol.
 var kMaxProtocolStringLength = 80;
 
 // Different kind of properties.
 var PropertyKind = {};
 PropertyKind.Named   = 1;
 PropertyKind.Indexed = 2;
 
 
@@ skipping 35 matching lines @@
 //       - StringMirror
 //       - SymbolMirror
 //       - ObjectMirror
 //         - FunctionMirror
 //           - UnresolvedFunctionMirror
 //         - ArrayMirror
 //         - DateMirror
 //         - RegExpMirror
 //         - ErrorMirror
 //         - PromiseMirror
+//         - MapMirror
 //     - PropertyMirror
 //     - InternalPropertyMirror
 //     - FrameMirror
 //     - ScriptMirror
 
 
 /**
  * Base class for all mirror objects.
  * @param {string} type The type of the mirror
  * @constructor
@@ skipping 191 matching lines @@
 /**
  * Check whether the mirror reflects a scope.
  * @returns {boolean} True if the mirror reflects a scope
  */
 Mirror.prototype.isScope = function() {
   return this instanceof ScopeMirror;
 };
 
 
 /**
+ * Check whether the mirror reflects a map.
+ * @returns {boolean} True if the mirror reflects a map
+ */
+Mirror.prototype.isMap = function() {
+  return this instanceof MapMirror;
+};
+
+
+/**
  * Allocate a handle id for this object.
  */
 Mirror.prototype.allocateHandle_ = function() {
   if (mirror_cache_enabled_) this.handle_ = next_handle_++;
 };
 
 
 /**
  * Allocate a transient handle id for this object. Transient handles are
  * negative.
@@ skipping 812 matching lines @@
 PromiseMirror.prototype.status = function() {
   return PromiseGetStatus_(this.value_);
 };
 
 
 PromiseMirror.prototype.promiseValue = function() {
   return MakeMirror(PromiseGetValue_(this.value_));
 };
 
 
+function MapMirror(value) {
+  %_CallFunction(this, value, MAP_TYPE, ObjectMirror);
+}
+inherits(MapMirror, ObjectMirror);
+
+
+/**
+ * Returns an array of key/value pairs of a map.
+ * This will keep keys alive for WeakMaps.
+ *
+ * @returns {Array.<Object>} Array of key/value pairs of a map.
+ */
+MapMirror.prototype.entries = function() {
+  var result = [];
+
+  if (IS_WEAKMAP(this.value_)) {
+    var entries = %GetWeakMapEntries(this.value_);
+    for (var i = 0; i < entries.length; i += 2) {
+      result.push({
+        key: entries[i],
+        value: entries[i + 1]
+      });
+    }
+    return result;
+  }
+
+  var iter = %_CallFunction(this.value_, builtins.MapEntries);
+  var next;
+  while (!(next = iter.next()).done) {
+    result.push({
+      key: next.value[0],
+      value: next.value[1]
+    });
+  }
+  return result;
+};
+
+
 /**
  * Base mirror object for properties.
  * @param {ObjectMirror} mirror The mirror object having this property
  * @param {string} name The name of the property
  * @param {Array} details Details about the property
  * @constructor
  * @extends Mirror
  */
 function PropertyMirror(mirror, name, details) {
   %_CallFunction(this, PROPERTY_TYPE, Mirror);
@@ skipping 1512 matching lines @@
   }
   if (!NUMBER_IS_FINITE(value)) {
     if (value > 0) {
       return 'Infinity';
     } else {
       return '-Infinity';
     }
   }
   return value;
 }