Creating a common library for all DOM types.

sdk/lib/html/src/dart2js_Conversions.dart

 // 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.
 
 
 // Conversions for IDBKey.
 //
 // Per http://www.w3.org/TR/IndexedDB/#key-construct
 //
 // "A value is said to be a valid key if it is one of the following types: Array
@@ skipping 76 matching lines @@
 // with native names.
 _convertDartToNative_ImageData(ImageData imageData) {
   if (imageData is _TypedImageData) {
     return JS('', '{data: #, height: #, width: #}',
         imageData.data, imageData.height, imageData.width);
   }
   return imageData;
 }
 
 
-/// Converts a JavaScript object with properties into a Dart Map.
-/// Not suitable for nested objects.
-Map _convertNativeToDart_Dictionary(object) {
-  if (object == null) return null;
-  var dict = {};
-  for (final key in JS('=List', 'Object.getOwnPropertyNames(#)', object)) {
-    dict[key] = JS('var', '#[#]', object, key);
-  }
-  return dict;
-}
-
-/// Converts a flat Dart map into a JavaScript object with properties.
-_convertDartToNative_Dictionary(Map dict) {
-  if (dict == null) return null;
-  var object = JS('var', '{}');
-  dict.forEach((String key, value) {
-      JS('void', '#[#] = #', object, key, value);
-    });
-  return object;
-}
-
-
-/**
- * Ensures that the input is a JavaScript Array.
- *
- * Creates a new JavaScript array if necessary, otherwise returns the original.
- */
-List _convertDartToNative_StringArray(List<String> input) {
-  // TODO(sra).  Implement this.
-  return input;
-}
-
-
 // -----------------------------------------------------------------------------
 
 /**
  * Converts a native IDBKey into a Dart object.
  *
  * May return the original input.  May mutate the original input (but will be
  * idempotent if mutation occurs).  It is assumed that this conversion happens
  * on native IDBKeys on all paths that return IDBKeys from native DOM calls.
  *
  * If necessary, JavaScript Dates are converted into Dart Dates.
  */
 _convertNativeToDart_IDBKey(nativeKey) {
   containsDate(object) {
-    if (_isJavaScriptDate(object)) return true;
+    if (isJavaScriptDate(object)) return true;
     if (object is List) {
       for (int i = 0; i < object.length; i++) {
         if (containsDate(object[i])) return true;
       }
     }
     return false;  // number, string.
   }
   if (containsDate(nativeKey)) {
     throw new UnimplementedError('IDBKey containing Date');
   }
@@ skipping 11 matching lines @@
  */
 _convertDartToNative_IDBKey(dartKey) {
   // TODO: Implement.
   return dartKey;
 }
 
 
 
 /// May modify original.  If so, action is idempotent.
 _convertNativeToDart_IDBAny(object) {
-  return _convertNativeToDart_AcceptStructuredClone(object, mustCopy: false);
+  return convertNativeToDart_AcceptStructuredClone(object, mustCopy: false);
 }
 
-/// Converts a Dart value into a JavaScript SerializedScriptValue.
-_convertDartToNative_SerializedScriptValue(value) {
-  return _convertDartToNative_PrepareForStructuredClone(value);
-}
-
-/// Since the source object may be viewed via a JavaScript event listener the
-/// original may not be modified.
-_convertNativeToDart_SerializedScriptValue(object) {
-  return _convertNativeToDart_AcceptStructuredClone(object, mustCopy: true);
-}
-
-
-/**
- * Converts a Dart value into a JavaScript SerializedScriptValue.  Returns the
- * original input or a functional 'copy'.  Does not mutate the original.
- *
- * The main transformation is the translation of Dart Maps are converted to
- * JavaScript Objects.
- *
- * The algorithm is essentially a dry-run of the structured clone algorithm
- * described at
- * http://www.whatwg.org/specs/web-apps/current-work/multipage/common-dom-interfaces.html#structured-clone
- * https://www.khronos.org/registry/typedarray/specs/latest/#9
- *
- * Since the result of this function is expected to be passed only to JavaScript
- * operations that perform the structured clone algorithm which does not mutate
- * its output, the result may share structure with the input [value].
- */
-_convertDartToNative_PrepareForStructuredClone(value) {
-
-  // TODO(sra): Replace slots with identity hash table.
-  var values = [];
-  var copies = [];  // initially 'null', 'true' during initial DFS, then a copy.
-
-  int findSlot(value) {
-    int length = values.length;
-    for (int i = 0; i < length; i++) {
-      if (identical(values[i], value)) return i;
-    }
-    values.add(value);
-    copies.add(null);
-    return length;
-  }
-  readSlot(int i) => copies[i];
-  writeSlot(int i, x) { copies[i] = x; }
-  cleanupSlots() {}  // Will be needed if we mark objects with a property.
-
-  // Returns the input, or a clone of the input.
-  walk(e) {
-    if (e == null) return e;
-    if (e is bool) return e;
-    if (e is num) return e;
-    if (e is String) return e;
-    if (e is Date) {
-      // TODO(sra).
-      throw new UnimplementedError('structured clone of Date');
-    }
-    if (e is RegExp) {
-      // TODO(sra).
-      throw new UnimplementedError('structured clone of RegExp');
-    }
-
-    // The browser's internal structured cloning algorithm will copy certain
-    // types of object, but it will copy only its own implementations and not
-    // just any Dart implementations of the interface.
-
-    // TODO(sra): The JavaScript objects suitable for direct cloning by the
-    // structured clone algorithm could be tagged with an private interface.
-
-    if (e is File) return e;
-    if (e is Blob) return e;
-    if (e is _FileList) return e;
-
-    // TODO(sra): Firefox: How to convert _TypedImageData on the other end?
-    if (e is ImageData) return e;
-    if (e is ArrayBuffer) return e;
-
-    if (e is ArrayBufferView) return e;
-
-    if (e is Map) {
-      var slot = findSlot(e);
-      var copy = readSlot(slot);
-      if (copy != null) return copy;
-      copy = JS('var', '{}');
-      writeSlot(slot, copy);
-      e.forEach((key, value) {
-          JS('void', '#[#] = #', copy, key, walk(value));
-        });
-      return copy;
-    }
-
-    if (e is List) {
-      // Since a JavaScript Array is an instance of Dart List it is possible to
-      // avoid making a copy of the list if there is no need to copy anything
-      // reachable from the array.  We defer creating a new array until a cycle
-      // is detected or a subgraph was copied.
-      int length = e.length;
-      var slot = findSlot(e);
-      var copy = readSlot(slot);
-      if (copy != null) {
-        if (true == copy) {  // Cycle, so commit to making a copy.
-          copy = JS('=List', 'new Array(#)', length);
-          writeSlot(slot, copy);
-        }
-        return copy;
-      }
-
-      int i = 0;
-
-      if (_isJavaScriptArray(e) &&
-          // We have to copy immutable lists, otherwise the structured clone
-          // algorithm will copy the .immutable$list marker property, making the
-          // list immutable when received!
-          !_isImmutableJavaScriptArray(e)) {
-        writeSlot(slot, true);  // Deferred copy.
-        for ( ; i < length; i++) {
-          var element = e[i];
-          var elementCopy = walk(element);
-          if (!identical(elementCopy, element)) {
-            copy = readSlot(slot);   // Cyclic reference may have created it.
-            if (true == copy) {
-              copy = JS('=List', 'new Array(#)', length);
-              writeSlot(slot, copy);
-            }
-            for (int j = 0; j < i; j++) {
-              copy[j] = e[j];
-            }
-            copy[i] = elementCopy;
-            i++;
-            break;
-          }
-        }
-        if (copy == null) {
-          copy = e;
-          writeSlot(slot, copy);
-        }
-      } else {
-        // Not a JavaScript Array.  We are forced to make a copy.
-        copy = JS('=List', 'new Array(#)', length);
-        writeSlot(slot, copy);
-      }
-
-      for ( ; i < length; i++) {
-        copy[i] = walk(e[i]);
-      }
-      return copy;
-    }
-
-    throw new UnimplementedError('structured clone of other type');
-  }
-
-  var copy = walk(value);
-  cleanupSlots();
-  return copy;
-}
-
-/**
- * Converts a native value into a Dart object.
- *
- * If [mustCopy] is [:false:], may return the original input.  May mutate the
- * original input (but will be idempotent if mutation occurs).  It is assumed
- * that this conversion happens on native serializable script values such values
- * from native DOM calls.
- *
- * [object] is the result of a structured clone operation.
- *
- * If necessary, JavaScript Dates are converted into Dart Dates.
- *
- * If [mustCopy] is [:true:], the entire object is copied and the original input
- * is not mutated.  This should be the case where Dart and JavaScript code can
- * access the value, for example, via multiple event listeners for
- * MessageEvents.  Mutating the object to make it more 'Dart-like' would corrupt
- * the value as seen from the JavaScript listeners.
- */
-_convertNativeToDart_AcceptStructuredClone(object, {mustCopy = false}) {
-
-  // TODO(sra): Replace slots with identity hash table that works on non-dart
-  // objects.
-  var values = [];
-  var copies = [];
-
-  int findSlot(value) {
-    int length = values.length;
-    for (int i = 0; i < length; i++) {
-      if (identical(values[i], value)) return i;
-    }
-    values.add(value);
-    copies.add(null);
-    return length;
-  }
-  readSlot(int i) => copies[i];
-  writeSlot(int i, x) { copies[i] = x; }
-
-  walk(e) {
-    if (e == null) return e;
-    if (e is bool) return e;
-    if (e is num) return e;
-    if (e is String) return e;
-
-    if (_isJavaScriptDate(e)) {
-      // TODO(sra).
-      throw new UnimplementedError('structured clone of Date');
-    }
-
-    if (_isJavaScriptRegExp(e)) {
-      // TODO(sra).
-      throw new UnimplementedError('structured clone of RegExp');
-    }
-
-    if (_isJavaScriptSimpleObject(e)) {
-      // TODO(sra): If mustCopy is false, swizzle the prototype for one of a Map
-      // implementation that uses the properies as storage.
-      var slot = findSlot(e);
-      var copy = readSlot(slot);
-      if (copy != null) return copy;
-      copy = {};
-
-      writeSlot(slot, copy);
-      for (final key in JS('=List', 'Object.keys(#)', e)) {
-        copy[key] = walk(JS('var', '#[#]', e, key));
-      }
-      return copy;
-    }
-
-    if (_isJavaScriptArray(e)) {
-      var slot = findSlot(e);
-      var copy = readSlot(slot);
-      if (copy != null) return copy;
-
-      int length = e.length;
-      // Since a JavaScript Array is an instance of Dart List, we can modify it
-      // in-place unless we must copy.
-      copy = mustCopy ? JS('=List', 'new Array(#)', length) : e;
-      writeSlot(slot, copy);
-
-      for (int i = 0; i < length; i++) {
-        copy[i] = walk(e[i]);
-      }
-      return copy;
-    }
-
-    // Assume anything else is already a valid Dart object, either by having
-    // already been processed, or e.g. a clonable native class.
-    return e;
-  }
-
-  var copy = walk(object);
-  return copy;
-}
-
-
-bool _isJavaScriptDate(value) => JS('bool', '# instanceof Date', value);
-bool _isJavaScriptRegExp(value) => JS('bool', '# instanceof RegExp', value);
-bool _isJavaScriptArray(value) => JS('bool', '# instanceof Array', value);
-bool _isJavaScriptSimpleObject(value) =>
-    JS('bool', 'Object.getPrototypeOf(#) === Object.prototype', value);
-bool _isImmutableJavaScriptArray(value) =>
-    JS('bool', r'!!(#.immutable$list)', value);
-
-
-
-const String _serializedScriptValue =
-    'num|String|bool|'
-    '=List|=Object|'
-    'Blob|File|ArrayBuffer|ArrayBufferView'
-    // TODO(sra): Add Date, RegExp.
-    ;
-const _annotation_Creates_SerializedScriptValue =
-    const Creates(_serializedScriptValue);
-const _annotation_Returns_SerializedScriptValue =
-    const Returns(_serializedScriptValue);
 
 const String _idbKey = '=List|=Object|num|String';  // TODO(sra): Add Date.
 const _annotation_Creates_IDBKey = const Creates(_idbKey);
 const _annotation_Returns_IDBKey = const Returns(_idbKey);