Update all Angular libs (run update_all.sh).

third_party/pkg/angular/lib/directive/ng_repeat.dart

 part of angular.directive;
 
-class _Row {
-  var id;
-  Scope scope;
-  Block block;
-  dom.Element startNode;
-  dom.Element endNode;
-  List<dom.Element> elements;
-
-  _Row(this.id);
-}
-
 /**
  * The `ngRepeat` directive instantiates a template once per item from a
  * collection. Each template instance gets its own scope, where the given loop
  * variable is set to the current collection item, and `$index` is set to the
  * item index or key.
  *
  * Special properties are exposed on the local scope of each template instance,
  * including:
  *
- * <table>
- * <tr><th> Variable  </th><th> Type </th><th> Details                                                                     <th></tr>
- * <tr><td> `$index`  </td><td>[num] </td><td> iterator offset of the repeated element (0..length-1)                       <td></tr>
- * <tr><td> `$first`  </td><td>[bool]</td><td> true if the repeated element is first in the iterator.                      <td></tr>
- * <tr><td> `$middle` </td><td>[bool]</td><td> true if the repeated element is between the first and last in the iterator. <td></tr>
- * <tr><td> `$last`   </td><td>[bool]</td><td> true if the repeated element is last in the iterator.                       <td></tr>
- * <tr><td> `$even`   </td><td>[bool]</td><td> true if the iterator position `$index` is even (otherwise false).           <td></tr>
- * <tr><td> `$odd`    </td><td>[bool]</td><td> true if the iterator position `$index` is odd (otherwise false).            <td></tr>
- * </table>
+ *   * `$index` ([:num:]) the iterator offset of the repeated element
+ *      (0..length-1)
+ *   * `$first`  ([:bool:]) whether the repeated element is first in the
+ *      iterator.
+ *   * `$middle` ([:bool:]) whether the repeated element is between the first
+ *      and last in the iterator.
+ *   * `$last` ([:bool:]) whether the repeated element is last in the iterator.
+ *   * `$even` ([:bool:]) whether the iterator position `$index` is even.
+ *   * `$odd` ([:bool:]) whether the iterator position `$index` is odd.
  *
  *
  * [repeat_expression] ngRepeat The expression indicating how to enumerate a
  * collection. These formats are currently supported:
  *
  *   * `variable in expression` – where variable is the user defined loop
  *   variable and `expression` is a scope expression giving the collection to
  *   enumerate.
  *
  *     For example: `album in artist.albums`.
  *
  *   * `variable in expression track by tracking_expression` – You can also
  *   provide an optional tracking function which can be used to associate the
  *   objects in the collection with the DOM elements. If no tracking function is
  *   specified the ng-repeat associates elements by identity in the collection.
  *   It is an error to have more than one tracking function to resolve to the
  *   same key. (This would mean that two distinct objects are mapped to the same
  *   DOM element, which is not possible.)  Filters should be applied to the
  *   expression, before specifying a tracking expression.
  *
  *     For example: `item in items` is equivalent to `item in items track by
  *     $id(item)`. This implies that the DOM elements will be associated by item
  *     identity in the array.
  *
  *     For example: `item in items track by $id(item)`. A built in `$id()`
  *     function can be used to assign a unique `$$hashKey` property to each item
  *     in the array. This property is then used as a key to associated DOM
  *     elements with the corresponding item in the array by identity. Moving the
- *     same object in array would move the DOM element in the same way ian the
+ *     same object in array would move the DOM element in the same way in the
  *     DOM.
  *
  *     For example: `item in items track by item.id` is a typical pattern when
  *     the items come from the database. In this case the object identity does
  *     not matter. Two objects are considered equivalent as long as their `id`
  *     property is same.
  *
  *     For example: `item in items | filter:searchText track by item.id` is a
- *     pattern that might be used to apply a filter to items in conjunction with
+ *     pattern that might be used to apply a formatter to items in conjunction with
  *     a tracking expression.
  *
  * # Example:
  *
  *     <ul>
  *       <li ng-repeat="item in ['foo', 'bar', 'baz']">{{item}}</li>
  *     </ul>
  */
 
-@NgDirective(
-    children: NgAnnotation.TRANSCLUDE_CHILDREN,
+@Decorator(
+    children: Directive.TRANSCLUDE_CHILDREN,
     selector: '[ng-repeat]',
     map: const {'.': '@expression'})
-class NgRepeatDirective extends AbstractNgRepeatDirective {
-  NgRepeatDirective(BlockHole blockHole,
-                    BoundBlockFactory boundBlockFactory,
-                    Scope scope,
-                    Parser parser,
-                    AstParser astParser)
-      : super(blockHole, boundBlockFactory, scope, parser, astParser);
-}
+class NgRepeat {
+  static RegExp _SYNTAX = new RegExp(r'^\s*(.+)\s+in\s+(.*?)\s*(?:track\s+by\s+(.+)\s*)?(\s+lazily\s*)?$');
+  static RegExp _LHS_SYNTAX = new RegExp(r'^(?:([$\w]+)|\(([$\w]+)\s*,\s*([$\w]+)\))$');
 
-/**
- * *EXPERIMENTAL:* This feature is experimental. We reserve the right to change
- * or delete it.
- *
- * [ng-shallow-repeat] is same as [ng-repeat] with some tradeoffs designed for
- * speed. Use [ng-shallow-repeat] when you expect that your items you are
- * repeating over do not change during the repeater lifetime.
- *
- * The shallow repeater introduces these changes:
- *
- *  * The repeater only fires if the identity of the list changes or if the list
- *  [length] property changes. This means that the repeater will still see
- *  additions and deletions but not changes to the array.
- *  * The child scopes for each item are created in the lazy mode
- *  (see [Scope.$new]). This means the scopes are effectively taken out of the
- *  digest cycle and will not update on changes to the model.
- *
- */
-@deprecated
-@NgDirective(
-    children: NgAnnotation.TRANSCLUDE_CHILDREN,
-    selector: '[ng-shallow-repeat]',
-    map: const {'.': '@expression'})
-//TODO(misko): delete me, since we can no longer do shallow digest.
-class NgShallowRepeatDirective extends AbstractNgRepeatDirective {
-  NgShallowRepeatDirective(BlockHole blockHole,
-                          BoundBlockFactory boundBlockFactory,
-                          Scope scope,
-                          Parser parser,
-                          AstParser astParser)
-      : super(blockHole, boundBlockFactory, scope, parser, astParser)
-  {
-    print('DEPRECATED: [ng-shallow-repeat] use [ng-repeat]');
-  }
-}
-
-abstract class AbstractNgRepeatDirective  {
-  static RegExp _SYNTAX = new RegExp(r'^\s*(.+)\s+in\s+(.*?)\s*(\s+track\s+by\s+(.+)\s*)?(\s+lazily\s*)?$');
-  static RegExp _LHS_SYNTAX = new RegExp(r'^(?:([\$\w]+)|\(([\$\w]+)\s*,\s*([\$\w]+)\))$');
-
-  final BlockHole _blockHole;
-  final BoundBlockFactory _boundBlockFactory;
+  final ViewPort _viewPort;
+  final BoundViewFactory _boundViewFactory;
   final Scope _scope;
   final Parser _parser;
-  final AstParser _astParser;
+  final FormatterMap formatters;
 
   String _expression;
   String _valueIdentifier;
   String _keyIdentifier;
   String _listExpr;
-  Map<dynamic, _Row> _rows = {};
-  Function _trackByIdFn = (key, value, index) => value;
-  Watch _watch = null;
-  Iterable _lastCollection;
+  List<_Row> _rows;
+  Function _generateId = (key, value, index) => value;
+  Watch _watch;
 
-  AbstractNgRepeatDirective(this._blockHole, this._boundBlockFactory,
-                            this._scope, this._parser, this._astParser);
+  NgRepeat(this._viewPort, this._boundViewFactory, this._scope,
+           this._parser, this.formatters);
 
   set expression(value) {
+    assert(value != null);
     _expression = value;
     if (_watch != null) _watch.remove();
+
     Match match = _SYNTAX.firstMatch(_expression);
     if (match == null) {
       throw "[NgErr7] ngRepeat error! Expected expression in form of '_item_ "
           "in _collection_[ track by _id_]' but got '$_expression'.";
     }
+
     _listExpr = match.group(2);
-    var trackByExpr = match.group(4);
+
+    var trackByExpr = match.group(3);
     if (trackByExpr != null) {
       Expression trackBy = _parser(trackByExpr);
-      _trackByIdFn = ((key, value, index) {
-        final trackByLocals = <String, Object>{};
-        if (_keyIdentifier != null) trackByLocals[_keyIdentifier] = key;
-        trackByLocals
+      _generateId = ((key, value, index) {
+        final context = <String, Object>{}
             ..[_valueIdentifier] = value
             ..[r'$index'] = index
             ..[r'$id'] = (obj) => obj;
-        return relaxFnArgs(trackBy.eval)(new ScopeLocals(_scope.context, trackByLocals));
+        if (_keyIdentifier != null) context[_keyIdentifier] = key;
+        return relaxFnArgs(trackBy.eval)(new ScopeLocals(_scope.context,
+            context));
       });
     }
+
     var assignExpr = match.group(1);
     match = _LHS_SYNTAX.firstMatch(assignExpr);
     if (match == null) {
       throw "[NgErr8] ngRepeat error! '_item_' in '_item_ in _collection_' "
           "should be an identifier or '(_key_, _value_)' expression, but got "
           "'$assignExpr'.";
     }
+
     _valueIdentifier = match.group(3);
     if (_valueIdentifier == null) _valueIdentifier = match.group(1);
     _keyIdentifier = match.group(2);
 
     _watch = _scope.watch(
-        _astParser(_listExpr, collection: true),
-        (CollectionChangeRecord collection, _) {
-          //TODO(misko): we should take advantage of the CollectionChangeRecord!
-          _onCollectionChange(collection == null ? [] : collection.iterable);
-        }
+        _listExpr,
+        (CollectionChangeRecord changes, _) {
+          if (changes is! CollectionChangeRecord) return;
+          _onChange(changes);
+        },
+        collection: true,
+        formatters: formatters
     );
   }
 
-  List<_Row> _computeNewRows(Iterable collection, trackById) {
-    final newRowOrder = new List<_Row>(collection.length);
-    // Same as lastBlockMap but it has the current state. It will become the
-    // lastBlockMap on the next iteration.
-    final newRows = <dynamic, _Row>{};
-    // locate existing items
-    for (var index = 0; index < newRowOrder.length; index++) {
-      var value = collection.elementAt(index);
-      trackById = _trackByIdFn(index, value, index);
-      if (_rows.containsKey(trackById)) {
-        var row = _rows[trackById];
-        _rows.remove(trackById);
-        newRows[trackById] = row;
-        newRowOrder[index] = row;
-      } else if (newRows.containsKey(trackById)) {
-        // restore lastBlockMap
-        newRowOrder.forEach((row) {
-          if (row != null && row.startNode != null) _rows[row.id] = row;
-        });
-        // This is a duplicate and we need to throw an error
-        throw "[NgErr50] ngRepeat error! Duplicates in a repeater are not "
-            "allowed. Use 'track by' expression to specify unique keys. "
-            "Repeater: $_expression, Duplicate key: $trackById";
+  // Computes and executes DOM changes when the item list changes
+  void _onChange(CollectionChangeRecord changes) {
+    final int length = changes.length;
+    final rows = new List<_Row>(length);
+    final changeFunctions = new List<Function>(length);
+    final removedIndexes = <int>[];
+    final int domLength = _rows == null ? 0 : _rows.length;
+    final leftInDom = new List.generate(domLength, (i) => domLength - 1 - i);
+    var domIndex;
+
+    var addRow = (int index, value, View previousView) {
+      var childContext = _updateContext(new PrototypeMap(_scope.context), index,
+          length)..[_valueIdentifier] = value;
+      var childScope = _scope.createChild(childContext);
+      var view = _boundViewFactory(childScope);
+      var nodes = view.nodes;
+      rows[index] = new _Row(_generateId(index, value, index))
+          ..view = view
+          ..scope = childScope
+          ..nodes = nodes
+          ..startNode = nodes.first
+          ..endNode = nodes.last;
+      _viewPort.insert(view, insertAfter: previousView);
+    };
+
+    // todo(vicb) refactor once GH-774 gets fixed
+    if (_rows == null) {
+      _rows = new List<_Row>(length);
+      for (var i = 0; i < length; i++) {
+        changeFunctions[i] = (index, previousView) {
+          addRow(index, changes.iterable.elementAt(i), previousView);
+        };
+      }
+    } else {
+      changes.forEachRemoval((CollectionChangeItem removal) {
+        var index = removal.previousIndex;
+        var row = _rows[index];
+        row.scope.destroy();
+        _viewPort.remove(row.view);
+        leftInDom.removeAt(domLength - 1 - index);
+      });
+
+      changes.forEachAddition((CollectionChangeItem addition) {
+        changeFunctions[addition.currentIndex] = (index, previousView) {
+          addRow(index, addition.item, previousView);
+        };
+      });
+
+      changes.forEachMove((CollectionChangeItem move) {
+        var previousIndex = move.previousIndex;
+        var value = move.item;
+        changeFunctions[move.currentIndex] = (index, previousView) {
+          var previousRow = _rows[previousIndex];
+          var childScope = previousRow.scope;
+          var childContext = _updateContext(childScope.context, index, length);
+          if (!identical(childScope.context[_valueIdentifier], value)) {
+            childContext[_valueIdentifier] = value;
+          }
+          rows[index] = _rows[previousIndex];
+          // Only move the DOM node when required
+          if (domIndex < 0 || leftInDom[domIndex] != previousIndex) {
+            _viewPort.move(previousRow.view, moveAfter: previousView);
+            leftInDom.remove(previousIndex);
+          }
+          domIndex--;
+        };
+      });
+    }
+
+    var previousView = null;
+    domIndex = leftInDom.length - 1;
+    for(var targetIndex = 0; targetIndex < length; targetIndex++) {
+      var changeFn = changeFunctions[targetIndex];
+      if (changeFn == null) {
+        rows[targetIndex] = _rows[targetIndex];
+        domIndex--;
+        // The element has not moved but `$last` and `$middle` might still need
+        // to be updated
+        _updateContext(rows[targetIndex].scope.context, targetIndex, length);
       } else {
-        // new never before seen row
-        newRowOrder[index] = new _Row(trackById);
-        newRows[trackById] = null;
+        changeFn(targetIndex, previousView);
       }
+      previousView = rows[targetIndex].view;
     }
-    // remove existing items
-    _rows.forEach((key, row) {
-      row.block.remove();
-      row.scope.destroy();
-    });
-    _rows = newRows;
-    return newRowOrder;
+
+    _rows = rows;
   }
 
-  _onCollectionChange(Iterable collection) {
-    dom.Node previousNode = _blockHole.elements[0]; // current position of the node
-    dom.Node nextNode;
-    Scope childScope;
-    Map childContext;
-    Scope trackById;
-    ElementWrapper cursor = _blockHole;
-
-    List<_Row> newRowOrder = _computeNewRows(collection, trackById);
-
-    for (var index = 0; index < collection.length; index++) {
-      var value = collection.elementAt(index);
-      _Row row = newRowOrder[index];
-
-      if (row.startNode != null) {
-        // if we have already seen this object, then we need to reuse the
-        // associated scope/element
-        childScope = row.scope;
-        childContext = childScope.context as Map;
-
-        nextNode = previousNode;
-        do {
-          nextNode = nextNode.nextNode;
-        } while(nextNode != null);
-
-        // existing item which got moved
-        if (row.startNode != nextNode) row.block.moveAfter(cursor);
-        previousNode = row.endNode;
-      } else {
-        // new item which we don't know about
-        childScope = _scope.createChild(childContext = new PrototypeMap(_scope.context));
-      }
-
-      if (!identical(childScope.context[_valueIdentifier], value)) {
-        childContext[_valueIdentifier] = value;
-      }
-      var first = (index == 0);
-      var last = (index == collection.length - 1);
-      childContext
-          ..[r'$index'] = index
-          ..[r'$first'] = first
-          ..[r'$last'] = last
-          ..[r'$middle'] = !first && !last
-          ..[r'$odd'] = index & 1 == 1
-          ..[r'$even'] = index & 1 == 0;
-
-      if (row.startNode == null) {
-        var block = _boundBlockFactory(childScope);
-        _rows[row.id] = row
-            ..block = block
-            ..scope = childScope
-            ..elements = block.elements
-            ..startNode = row.elements[0]
-            ..endNode = row.elements[row.elements.length - 1];
-        block.insertAfter(cursor);
-      }
-      cursor = row.block;
-    }
+  PrototypeMap _updateContext(PrototypeMap context, int index, int length) {
+    var first = (index == 0);
+    var last = (index == length - 1);
+    return context
+        ..[r'$index'] = index
+        ..[r'$first'] = first
+        ..[r'$last'] = last
+        ..[r'$middle'] = !(first || last)
+        ..[r'$odd'] = index.isOdd
+        ..[r'$even'] = index.isEven;
   }
 }
+
+class _Row {
+  final id;
+  Scope scope;
+  View view;
+  dom.Element startNode;
+  dom.Element endNode;
+  List<dom.Element> nodes;
+
+  _Row(this.id);
+}