[Tests] Fix corelib_2/iterable_fold_test and iterable_reduce_test

* Change 'var iterable' to dynamic as type inference can only
  infer Object type.

* Explicitly set result type of closures passed to reduce() to
  make closure type compatible with parameter type expected by reduce().

* To modify List of Lists of int, add '[4]' instead of '4' to trigger
  expected ConcurrentModificationError instead of type error.

* Remove splitting to multi-test.

* Format with dartfmt.

Change-Id: Ie1a35eececbf1133cb2384afad10e9d355016abe
Reviewed-on: https://dart-review.googlesource.com/36300
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>

tests/corelib_2/corelib_2.status

@@ -15,7 +15,6 @@ apply3_test: CompileTimeError
 bool_from_environment2_test/03: Crash
 int_modulo_arith_test/modPow: RuntimeError
 int_modulo_arith_test/none: RuntimeError
-iterable_reduce_test/01: CompileTimeError
 map_test: Crash # crash in front_end.
 null_nosuchmethod_test/01: CompileTimeError
 null_nosuchmethod_test/none: CompileTimeError
@@ -234,13 +233,10 @@ integer_to_radix_string_test/02: RuntimeError
 integer_to_radix_string_test/none: RuntimeError
 integer_to_string_test/01: RuntimeError
 iterable_empty_test: Crash # 'file:*/pkg/compiler/lib/src/ssa/interceptor_simplifier.dart': Failed assertion: line 391 pos 16: 'receiver.nonCheck() == user.inputs[1].nonCheck()': is not true.
-iterable_fold_test/01: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_fold_test/02: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_fold_test/none: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
+iterable_fold_test: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
 iterable_generate_test/01: RuntimeError
 iterable_generate_test/none: RuntimeError
-iterable_reduce_test/01: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_reduce_test/none: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
+iterable_reduce_test: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
 iterable_return_type_test/01: RuntimeError
 iterable_return_type_test/02: RuntimeError
 iterable_return_type_test/none: RuntimeError
@@ -300,13 +296,10 @@ integer_to_radix_string_test/02: RuntimeError
 integer_to_radix_string_test/none: RuntimeError
 integer_to_string_test/01: RuntimeError
 iterable_empty_test: RuntimeError
-iterable_fold_test/01: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_fold_test/02: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_fold_test/none: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
+iterable_fold_test: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
 iterable_generate_test/01: RuntimeError
 iterable_generate_test/none: RuntimeError
-iterable_reduce_test/01: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
-iterable_reduce_test/none: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
+iterable_reduce_test: Crash # NoSuchMethodError: The getter 'isDynamic' was called on null.
 iterable_return_type_test/01: RuntimeError
 iterable_return_type_test/02: RuntimeError
 iterable_return_type_test/none: RuntimeError
@@ -409,9 +402,6 @@ bigint_test: Pass, Timeout # Please triage.
 [ $compiler == dartk && $runtime == vm && $strong ]
 apply3_test: CompileTimeError # Issue 31402 (Invocation arguments)
 bool_from_environment2_test/03: MissingCompileTimeError
-iterable_fold_test/02: RuntimeError
-iterable_reduce_test/01: CompileTimeError # Issue 31533
-iterable_reduce_test/none: RuntimeError
 iterable_to_list_test/01: RuntimeError
 iterable_to_list_test/none: RuntimeError
 json_map_test: RuntimeError
@@ -435,9 +425,6 @@ unicode_test: RuntimeError # Issue 18061: German double S.
 # ===== dartkp + dart_precompiled status lines =====
 [ $compiler == dartkp && $runtime == dart_precompiled && $strong ]
 bool_from_environment2_test/03: MissingCompileTimeError
-iterable_fold_test/02: RuntimeError
-iterable_reduce_test/01: CompileTimeError # Issue 31533
-iterable_reduce_test/none: RuntimeError
 iterable_to_list_test/01: RuntimeError
 iterable_to_list_test/none: RuntimeError
 json_map_test: RuntimeError
@@ -525,9 +512,6 @@ integer_arith_vm_test/modPow: RuntimeError # Issue 30170
 integer_parsed_arith_vm_test: RuntimeError # Issue 29921
 integer_to_radix_string_test: RuntimeError # Issue 29921
 integer_to_string_test/01: RuntimeError # Issue 29921
-iterable_fold_test/02: RuntimeError # different type inference problem
-iterable_reduce_test/01: RuntimeError
-iterable_reduce_test/none: RuntimeError
 iterable_return_type_test/02: RuntimeError # Issue 29921
 iterable_to_list_test/*: RuntimeError
 json_map_test: RuntimeError # Issue 29921
@@ -688,7 +672,6 @@ double_parse_test/02: Skip # Temporarily disable the following tests until we fi
 double_parse_test/03: Skip # Temporarily disable the following tests until we figure out why they started failing.
 double_parse_test/04: Skip # Temporarily disable the following tests until we figure out why they started failing.
 double_parse_test/none: Skip # Temporarily disable the following tests until we figure out why they started failing.
-iterable_reduce_test/01: CompileTimeError # Issue 31533
 
 [ $compiler == dartkp || $compiler == precompiler ]
 apply3_test: SkipByDesign

tests/corelib_2/iterable_fold_test.dart

@@ -19,7 +19,7 @@ class MyList extends ListBase {
   operator []=(index, val) => list[index] = val;
 }
 
-Iterable id (Iterable x) => x;
+Iterable id(Iterable x) => x;
 
 main() {
   for (dynamic iterable in [
@@ -35,10 +35,10 @@ main() {
     new List.generate(3, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x > 0),
     [0, 1, 2].map((x) => x + 1),
-    [ //# 01: ok
-      [1, 2], //# 01: ok
-      [3] //# 01: ok
-    ].expand(id), //# 01: ok
+    [
+      [1, 2],
+      [3]
+    ].expand(id),
     [3, 2, 1].reversed,
     [0, 1, 2, 3].skip(1),
     [1, 2, 3, 4].take(3),
@@ -93,7 +93,7 @@ main() {
     new List.generate(0, (x) => x + 1),
     [0, 1, 2, 3].where((x) => false),
     [].map((x) => x + 1),
-    [[], []].expand(id), //# 01: ok
+    [[], []].expand(id),
     [].reversed,
     [0, 1, 2, 3].skip(4),
     [1, 2, 3, 4].take(0),
@@ -123,18 +123,18 @@ main() {
     new List.generate(1, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x == 1),
     [0].map((x) => x + 1),
-    [ //# 01: ok
-      [], //# 01: ok
-      [1] //# 01: ok
-    ].expand(id), //# 01: ok
+    [
+      [],
+      [1]
+    ].expand(id),
     [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, //# 02: ok
+    (new HashMap()..[0] = 1).values,
     (new SplayTreeMap()..[1] = 0).keys,
-    (new SplayTreeMap()..[0] = 1).values, //# 02: ok
+    (new SplayTreeMap()..[0] = 1).values,
     new HashSet()..add(1),
     new LinkedHashSet()..add(1),
     new SplayTreeSet()..add(1),
@@ -160,23 +160,27 @@ main() {
     collection.add(4);
   }
 
+  void addListOf4(collection) {
+    collection.add([4]);
+  }
+
   void put4(map) {
     map[4] = 4;
   }
 
-  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([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([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([0, 1, 2, 3], add4, (x) => x.where((int x) => x > 0));
+  testModification([0, 1, 2], add4, (x) => x.map((x) => x + 1));
+  testModification([
+    [1, 2],
+    [3]
+  ], addListOf4, (x) => x.expand((List<int> x) => x));
+  testModification([3, 2, 1], add4, (x) => x.reversed);
   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()

tests/corelib_2/iterable_reduce_test.dart

@@ -23,7 +23,7 @@ Iterable id(Iterable x) => x;
 
 main() {
   // Test functionality.
-  for (var iterable in [
+  for (dynamic iterable in [
     const [1, 2, 3],
     [1, 2, 3],
     new List(3)
@@ -36,10 +36,10 @@ main() {
     new List.generate(3, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x > 0),
     [0, 1, 2].map((x) => x + 1),
-    [ //# 01: ok
-      [1, 2], //# 01: ok
-      [3]  //# 01: ok
-    ].expand(id), //# 01: ok
+    [
+      [1, 2],
+      [3]
+    ].expand(id),
     [3, 2, 1].reversed,
     [0, 1, 2, 3].skip(1),
     [1, 2, 3, 4].take(3),
@@ -75,12 +75,13 @@ main() {
     new MyList([1, 2, 3]),
   ]) {
     int callCount = 0;
-    var result = iterable.reduce((x, y) { //# 01: ok
-      callCount++; //# 01: ok
-      return x + y; //# 01: ok
-    }); //# 01: ok
-    Expect.equals(6, result, "${iterable.runtimeType}"); //# 01: ok
-    Expect.equals(2, callCount); //# 01: ok
+    var result = iterable.reduce((x, y) {
+      callCount++;
+      // Return type of reduce() callback should match element type.
+      return (x + y) as int;
+    });
+    Expect.equals(6, result, "${iterable.runtimeType}");
+    Expect.equals(2, callCount);
   }
 
   // Empty iterables not allowed.
@@ -94,7 +95,7 @@ main() {
     new List.generate(0, (x) => x + 1),
     [0, 1, 2, 3].where((x) => false),
     [].map((x) => x + 1),
-    [[], []].expand(id), //# 01: ok
+    [[], []].expand(id),
     [].reversed,
     [0, 1, 2, 3].skip(4),
     [1, 2, 3, 4].take(0),
@@ -110,12 +111,12 @@ main() {
     "".runes,
     new MyList([]),
   ]) {
-    Expect.throwsStateError(
-        () => iterable.reduce((x, y) => throw "Unreachable"));
+    Expect
+        .throwsStateError(() => iterable.reduce((x, y) => throw "Unreachable"));
   }
 
   // Singleton iterables not calling reduce function.
-  for (var iterable in [
+  for (dynamic iterable in [
     const [1],
     [1],
     new List(1)..[0] = 1,
@@ -125,10 +126,10 @@ main() {
     new List.generate(1, (x) => x + 1),
     [0, 1, 2, 3].where((x) => x == 1),
     [0].map((x) => x + 1),
-    [ //# 01: ok
-      [], //# 01: ok
-      [1] //# 01: ok
-    ].expand(id), //# 01: ok
+    [
+      [],
+      [1]
+    ].expand(id),
     [1].reversed,
     [0, 1].skip(1),
     [1, 2, 3, 4].take(1),
@@ -144,7 +145,7 @@ main() {
     "\x01".runes,
     new MyList([1]),
   ]) {
-    Expect.equals(1, iterable.reduce((x, y) => throw "Unreachable")); //# 01: ok
+    Expect.equals(1, iterable.reduce((x, y) => throw "Unreachable"));
   }
 
   // Concurrent modifications not allowed.
@@ -153,7 +154,8 @@ main() {
     Expect.throws(() {
       iterable.reduce((x, y) {
         modify(base);
-        return x + y;
+        // Return type of reduce() callback should match element type.
+        return (x + y) as int;
       });
     }, (e) => e is ConcurrentModificationError);
   }
@@ -162,6 +164,10 @@ main() {
     collection.add(4);
   }
 
+  void addListOf4(collection) {
+    collection.add([4]);
+  }
+
   void put4(map) {
     map[4] = 4;
   }
@@ -172,12 +178,12 @@ main() {
   testModification(new SplayTreeSet()..add(1)..add(2)..add(3), add4, id);
   testModification(new MyList([1, 2, 3]), add4, id);
 
-  testModification([0, 1, 2, 3], add4, (x) => x.where((x) => x > 0));
+  testModification([0, 1, 2, 3], add4, (x) => x.where((int x) => x > 0));
   testModification([0, 1, 2], add4, (x) => x.map((x) => x + 1));
   testModification([
     [1, 2],
     [3]
-  ], add4, (x) => x.expand((x) => x));
+  ], addListOf4, (x) => x.expand((List<int> x) => x));
   testModification([3, 2, 1], add4, (x) => x.reversed);
   testModification({1: 1, 2: 2, 3: 3}, put4, (x) => x.keys);
   testModification({1: 1, 2: 2, 3: 3}, put4, (x) => x.values);