Migrate test block 10 to Dart 2.0.

tests/corelib_2/iterable_fold_test.dart

 // Copyright (c) 2014, 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 "package:expect/expect.dart";
 import 'dart:collection';
 import 'dart:typed_data';
 
 class MyList extends ListBase {
   List list;
   MyList(this.list);
 
   get length => list.length;
   set length(val) {
     list.length = val;
   }
 
   operator [](index) => list[index];
   operator []=(index, val) => list[index] = val;
 }
 
-id(x) => x;
+id (x) => x;
 
 main() {
-  for (var iterable in [
+  for (dynamic iterable in [
     const [1, 2, 3],
     [1, 2, 3],
     new List(3)
       ..[0] = 1
       ..[1] = 2
       ..[2] = 3,
     {1: 1, 2: 2, 3: 3}.keys,
     {1: 1, 2: 2, 3: 3}.values,
     new Iterable.generate(3, (x) => x + 1),
     new List.generate(3, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x > 0),
     [0, 1, 2].map((x) => x + 1),
-    [
-      [1, 2],
-      [3]
-    ].expand(id),
+    [ //# 01: ok
+      [1, 2], //# 01: ok
+      [3] //# 01: ok
+    ].expand(id), //# 01: ok
     [3, 2, 1].reversed,
     [0, 1, 2, 3].skip(1),
     [1, 2, 3, 4].take(3),
     new Uint8List(3)
       ..[0] = 1
       ..[1] = 2
       ..[2] = 3,
     (new HashMap()
           ..[1] = 1
           ..[2] = 2
@@ skipping 34 matching lines @@
   for (var iterable in [
     const [],
     [],
     new List(0),
     {}.keys,
     {}.values,
     new Iterable.generate(0, (x) => x + 1),
     new List.generate(0, (x) => x + 1),
     [0, 1, 2, 3].where((x) => false),
     [].map((x) => x + 1),
-    [[], []].expand(id),
+    [[], []].expand(id), //# 01: ok
     [].reversed,
     [0, 1, 2, 3].skip(4),
     [1, 2, 3, 4].take(0),
     new Uint8List(0),
     (new HashMap()).keys,
     (new HashMap()).values,
     (new SplayTreeMap()).keys,
     (new SplayTreeMap()).values,
     new HashSet(),
     new LinkedHashSet(),
     new SplayTreeSet(),
     "".codeUnits,
     "".runes,
     new MyList([]),
   ]) {
     Expect.equals(42, iterable.fold(42, (x, y) => throw "Unreachable"));
   }
 
   // Singleton iterables are calling reduce function.
-  for (var iterable in [
+  for (dynamic iterable in [
     const [1],
     [1],
     new List(1)..[0] = 1,
     {1: 1}.keys,
     {1: 1}.values,
     new Iterable.generate(1, (x) => x + 1),
     new List.generate(1, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x == 1),
     [0].map((x) => x + 1),
-    [
-      [],
-      [1]
-    ].expand(id),
+    [ //# 01: ok
+      [], //# 01: ok
+      [1] //# 01: ok
+    ].expand(id), //# 01: ok
     [1].reversed,
     [0, 1].skip(1),
     [1, 2, 3, 4].take(1),
     new Uint8List(1)..[0] = 1,
     (new HashMap()..[1] = 0).keys,
-    (new HashMap()..[0] = 1).values,
+    (new HashMap()..[0] = 1).values, //# 02: ok
     (new SplayTreeMap()..[1] = 0).keys,
-    (new SplayTreeMap()..[0] = 1).values,
+    (new SplayTreeMap()..[0] = 1).values, //# 02: ok
     new HashSet()..add(1),
     new LinkedHashSet()..add(1),
     new SplayTreeSet()..add(1),
     "\x01".codeUnits,
     "\x01".runes,
     new MyList([1]),
   ]) {
     Expect.equals(43, iterable.fold(42, (x, y) => x + y));
   }
 
   // Concurrent modifications not allowed.
   testModification(base, modify, transform) {
     var iterable = transform(base);
     Expect.throws(() {
       iterable.fold(0, (x, y) {
         modify(base);
         return x + y;
       });
     }, (e) => e is ConcurrentModificationError);
   }
 
   void add4(collection) {
     collection.add(4);
   }
 
   void put4(map) {
     map[4] = 4;
   }
 
-  testModification([1, 2, 3], add4, id);
-  testModification(new HashSet()..add(1)..add(2)..add(3), add4, id);
-  testModification(new LinkedHashSet()..add(1)..add(2)..add(3), add4, id);
-  testModification(new SplayTreeSet()..add(1)..add(2)..add(3), add4, id);
-  testModification(new MyList([1, 2, 3]), add4, id);
+  testModification([1, 2, 3], add4, id); //# 02: ok
+  testModification(new HashSet()..add(1)..add(2)..add(3), add4, id); //# 02: ok
+  testModification(new LinkedHashSet()..add(1)..add(2)..add(3), add4, id); //# 02: ok
+  testModification(new SplayTreeSet()..add(1)..add(2)..add(3), add4, id); //# 02: ok
+  testModification(new MyList([1, 2, 3]), add4, id); //# 02: ok
 
-  testModification([0, 1, 2, 3], add4, (x) => x.where((x) => x > 0));
-  testModification([0, 1, 2], add4, (x) => x.map((x) => x + 1));
-  testModification([
-    [1, 2],
-    [3]
-  ], add4, (x) => x.expand((x) => x));
-  testModification([3, 2, 1], add4, (x) => x.reversed);
+  testModification([0, 1, 2, 3], add4, (x) => x.where((x) => x > 0)); //# 02: ok
+  testModification([0, 1, 2], add4, (x) => x.map((x) => x + 1)); //# 02: ok
+  testModification([ //# 02: ok
+    [1, 2], //# 02: ok
+    [3] //# 02: ok
+  ], add4, (x) => x.expand((x) => x)); //# 02: ok
+  testModification([3, 2, 1], add4, (x) => x.reversed); //# 02: ok
   testModification({1: 1, 2: 2, 3: 3}, put4, (x) => x.keys);
   testModification({1: 1, 2: 2, 3: 3}, put4, (x) => x.values);
   var hashMap = new HashMap()
     ..[1] = 1
     ..[2] = 2
     ..[3] = 3;
   testModification(hashMap, put4, (x) => x.keys);
   hashMap = new HashMap()
     ..[1] = 1
     ..[2] = 2
     ..[3] = 3;
   testModification(hashMap, put4, (x) => x.values);
   var splayMap = new SplayTreeMap()
     ..[1] = 1
     ..[2] = 2
     ..[3] = 3;
   testModification(splayMap, put4, (x) => x.keys);
   splayMap = new SplayTreeMap()
     ..[1] = 1
     ..[2] = 2
     ..[3] = 3;
   testModification(splayMap, put4, (x) => x.values);
 }