Use iterator, moveNext(), current.

pkg/unittest/lib/src/core_matchers.dart

Index: pkg/unittest/lib/src/core_matchers.dart
diff --git a/pkg/unittest/lib/src/core_matchers.dart b/pkg/unittest/lib/src/core_matchers.dart
index 20e9db2efbb2628e8a9bb4a0f55ad0961d2fadc0..cfb3254758a4ac56a120c0b8dc79722771c8c58f 100644
--- a/pkg/unittest/lib/src/core_matchers.dart
+++ b/pkg/unittest/lib/src/core_matchers.dart
@@ -98,15 +98,15 @@ class _DeepMatcher extends BaseMatcher {
     if (actual is !Iterable) {
       return 'is not Iterable';
     }
-    var expectedIterator = expected.iterator();
-    var actualIterator = actual.iterator();
+    var expectedIterator = expected.iterator;
+    var actualIterator = actual.iterator;
     var position = 0;
     String reason = null;
     while (reason == null) {
-      if (expectedIterator.hasNext) {
-        if (actualIterator.hasNext) {
-          Description r = matcher(expectedIterator.next(),
-                           actualIterator.next(),
+      if (expectedIterator.moveNext()) {
+        if (actualIterator.moveNext()) {
+          Description r = matcher(expectedIterator.current,
+                           actualIterator.current,
                            'mismatch at position ${position}',
                            depth);
           if (r != null) reason = r.toString();
@@ -114,7 +114,7 @@ class _DeepMatcher extends BaseMatcher {
         } else {
           reason = 'shorter than expected';
         }
-      } else if (actualIterator.hasNext) {
+      } else if (actualIterator.moveNext()) {
         reason = 'longer than expected';
       } else {
         return null;