a === b -> identical(a, b)

runtime/vm/snapshot_test.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.
 
 import 'dart:isolate';
 
 class Fields {
   Fields(int i, int j) : fld1 = i, fld2 = j, fld5 = true {}
   int fld1;
   final int fld2;
@@ skipping 97 matching lines @@
   }
 
   void build(int pile, int disks) {
     for (var i = disks - 1; i >= 0; i--) {
       push(pile, new TowersDisk(i));
     }
   }
 
   void push(int pile, TowersDisk disk) {
     TowersDisk top = piles[pile];
-    if ((top !== null) && (disk.size >= top.size))
+    if ((top != null) && (disk.size >= top.size))
       Error.error("Cannot put a big disk on a smaller disk.");
     disk.next = top;
     piles[pile] = disk;
   }
 
   TowersDisk pop(int pile) {
     var top = piles[pile];
-    if (top === null)
+    if (top == null)
       Error.error("Attempting to remove a disk from an empty pile.");
     piles[pile] = top.next;
     top.next = null;
     return top;
   }
 
   void moveTop(int from, int to) {
     push(to, pop(from));
     movesDone++;
   }
@@ skipping 382 matching lines @@
 // T r e e S o r t
 class TreeNodePress {
   int value;
   TreeNodePress left;
   TreeNodePress right;
 
   TreeNodePress(int n) : value = n {}
 
   void insert(int n) {
     if (n < value) {
-      if (left === null) left = new TreeNodePress(n);
+      if (left == null) left = new TreeNodePress(n);
       else left.insert(n);
     } else {
-      if (right === null) right = new TreeNodePress(n);
+      if (right == null) right = new TreeNodePress(n);
       else right.insert(n);
     }
   }
 
   void check() {
     TreeNodePress left = this.left;
     TreeNodePress right = this.right;
     int value = this.value;
 
-    return ((left === null) || ((left.value < value) && left.check())) &&
-           ((right === null) || ((right.value >= value) && right.check()));
+    return ((left == null) || ((left.value < value) && left.check())) &&
+           ((right == null) || ((right.value >= value) && right.check()));
   }
 }
 
 class TreeSort {
   static void sort(List<int> a) {
     int len = a.length;
     TreeNodePress tree = new TreeNodePress(a[0]);
     for (var i = 1; i < len; i++) tree.insert(a[i]);
     if (!tree.check()) Error.error("Invalid result, tree not sorted");
   }
@@ skipping 49 matching lines @@
     this.next = next;
 
   static ListElement makeList(int length) {
     if (length == 0) return null;
     return new ListElement(length, makeList(length - 1));
   }
 
   static bool isShorter(ListElement x, ListElement y) {
     ListElement xTail = x;
     ListElement yTail = y;
-    while (yTail !== null) {
-      if (xTail === null) return true;
+    while (yTail != null) {
+      if (xTail == null) return true;
       xTail = xTail.next;
       yTail = yTail.next;
     }
     return false;
   }
 }
 
 class Takl {
   static ListElement takl(ListElement x, ListElement y, ListElement z) {
     if (ListElement.isShorter(y, x)) {
@@ skipping 695 matching lines @@
     List sendObject = new List(5);
     sendObject[0] = local_list1;
     sendObject[1] = sendObject;
     sendObject[2] = local_list2;
     sendObject[3] = sendObject;
     sendObject[4] = local_list3;
     remote.call(sendObject).then((var replyObject) {
       Expect.equals(true, sendObject is List);
       Expect.equals(true, replyObject is List);
       Expect.equals(sendObject.length, replyObject.length);
-      Expect.equals(true, replyObject[1] === replyObject);
-      Expect.equals(true, replyObject[3] === replyObject);
-      Expect.equals(true, replyObject[0] === replyObject[2][1]);
-      Expect.equals(true, replyObject[0] === replyObject[2][2]);
-      Expect.equals(true, replyObject[2] === replyObject[4][0]);
-      Expect.equals(true, replyObject[0][0] === replyObject[0][2]);
+      Expect.equals(true, identical(replyObject[1], replyObject));
+      Expect.equals(true, identical(replyObject[3], replyObject));
+      Expect.equals(true, identical(replyObject[0], replyObject[2][1]));
+      Expect.equals(true, identical(replyObject[0], replyObject[2][2]));
+      Expect.equals(true, identical(replyObject[2], replyObject[4][0]));
+      Expect.equals(true, identical(replyObject[0][0], replyObject[0][2]));
       // Bigint literals are not canonicalized so do a == check.
       Expect.equals(true, replyObject[0][3] == replyObject[4][4]);
     });
 
     // Shutdown the MessageServer.
     remote.call(-1).then(expectAsync1((int message) {
         Expect.equals(MessageTest.elms.length + 1, message);
       }));
   });
 }
@@ skipping 101 matching lines @@
     _validated = new Completer<bool>();
   }
 
   void startClient(int id) {
     assert(_sent < N);
     final client = new LineProcessorClient(this, id);
     client.processLine(_sent++);
   }
 
   void notifyProcessedLine(LineProcessorClient client, int y, List<int> line) {
-    assert(_result[y] === null);
+    assert(_result[y] == null);
     _result[y] = line;
     _lineProcessedBy[y] = client;
 
     if (_sent != N) {
       client.processLine(_sent++);
     } else {
       client.shutdown();
     }
 
     // If all lines have been computed, validate the result.
@@ skipping 80 matching lines @@
 void processLines() {
   port.receive((message, SendPort replyTo) {
     if (message == TERMINATION_MESSAGE) {
       assert(replyTo == null);
       port.close();
     } else {
       replyTo.send(processLine(message), null);
     }
   });
 }