Fixes #993. DoublePointer tests added for FFI library

Author: sgrekhov

LibTest/ffi/Pointer/DoublePointer.asTypedList_t01.dart

@@ -0,0 +1,31 @@
+// Copyright (c) 2021, 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.
+
+/// @assertion Float64List asTypedList(int length)
+/// Creates a typed list view backed by memory in the address space.
+///
+/// The returned view will allow access to the memory range from address to
+/// address + 8 * length.
+///
+/// The user has to ensure the memory range is accessible while using the
+/// returned list.
+///
+/// @description Check that this getter/setter works as designed
+/// @author [email protected]
+
+import "dart:ffi";
+import 'dart:typed_data';
+import "package:ffi/ffi.dart";
+import '../../../Utils/expect.dart';
+
+void main() {
+  Pointer<Double> p = calloc<Double>(3);
+  p[0] = 3.14;
+  p[1] = 42.42;
+  p[2] = 1.1;
+  Float64List l = p.asTypedList(3);
+  Expect.equals(3.14, l[0]);
+  Expect.equals(42.42, l[1]);
+  Expect.equals(1.1, l[2]);
+}

LibTest/ffi/Pointer/DoublePointer.value_t01.dart

@@ -0,0 +1,22 @@
+// Copyright (c) 2021, 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.
+
+/// @assertion double value
+/// The double at address.
+///
+/// The address must be 8-byte aligned.
+///
+/// @description Check that this getter/setter works as designed
+/// @author [email protected]
+
+import "dart:ffi";
+import "package:ffi/ffi.dart";
+import '../../../Utils/expect.dart';
+
+void main() {
+  Pointer<Double> p = calloc<Double>();
+  Expect.equals(0, p.value);
+  p.value = 3.14;
+  Expect.equals(3.14, p.value);
+}

LibTest/ffi/Pointer/DoublePointer_A01_t01.dart

@@ -0,0 +1,26 @@
+// Copyright (c) 2021, 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.
+
+/// @assertion double operator [](int index)
+/// The double at address + 8 * index.
+///
+/// The address must be 8-byte aligned.
+///
+/// @description Check that operator [](int index) returns double at
+/// address + 8 * index.
+/// @author [email protected]
+
+import "dart:ffi";
+import 'dart:typed_data';
+import "package:ffi/ffi.dart";
+import '../../../Utils/expect.dart';
+
+void main() {
+  Pointer<Double> p1 = calloc<Double>(2);
+  Pointer<Double> p2 = new Pointer.fromAddress(p1.address + sizeOf<Double>());
+  p1.value = 1.1;
+  p2.value = 3.14;
+  Expect.equals(1.1, p1[0]);
+  Expect.equals(3.14, p1[1]);
+}

LibTest/ffi/Pointer/DoublePointer_A02_t01.dart

@@ -0,0 +1,27 @@
+// Copyright (c) 2021, 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.
+
+/// @assertion void operator []=(int index, double value)
+/// The double at address + 8 * index.
+///
+/// The address must be 8-byte aligned.
+///
+/// @description Check that operator [](int index) returns double at
+/// address + 8 * index.
+/// @author [email protected]
+
+import "dart:ffi";
+import 'dart:typed_data';
+import "package:ffi/ffi.dart";
+import '../../../Utils/expect.dart';
+
+void main() {
+  Pointer<Double> p1 = calloc<Double>(2);
+  Pointer<Double> p2 = new Pointer.fromAddress(p1.address + sizeOf<Double>());
+  p1[0] = 1.1;
+  p1[1] = 3.14;
+  Expect.equals(1.1, p1[0]);
+  Expect.equals(3.14, p1[1]);
+  Expect.equals(3.14, p2.value);
+}