Migrate test block 8 to Dart 2.0.

tests/corelib_strong/format_exception_test.dart

-// Copyright (c) 2011, 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.
-
-library format_exception_test;
-
-import "package:expect/expect.dart";
-
-test(exn, message, source, offset, toString) {
-  Expect.equals(message, exn.message);
-  Expect.equals(source, exn.source);
-  Expect.equals(offset, exn.offset);
-  Expect.equals(toString, exn.toString());
-}
-
-main() {
-  var e;
-  e = new FormatException();
-  test(e, "", null, null, "FormatException");
-  e = new FormatException("");
-  test(e, "", null, null, "FormatException");
-  e = new FormatException(null);
-  test(e, null, null, null, "FormatException");
-
-  e = new FormatException("message");
-  test(e, "message", null, null, "FormatException: message");
-
-  e = new FormatException("message", "source");
-  test(e, "message", "source", null, "FormatException: message\nsource");
-
-  e = new FormatException("message", "source" * 25);
-  test(e, "message", "source" * 25, null,
-      "FormatException: message\n" + "source" * 12 + "sou...");
-  e = new FormatException("message", "source" * 25);
-  test(e, "message", "source" * 25, null,
-      "FormatException: message\n" + "source" * 12 + "sou...");
-  e = new FormatException("message", "s1\nsource\ns2");
-  test(e, "message", "s1\nsource\ns2", null,
-      "FormatException: message\n" + "s1\nsource\ns2");
-
-  var o = new Object();
-  e = new FormatException("message", o, 10);
-  test(e, "message", o, 10, "FormatException: message (at offset 10)");
-
-  e = new FormatException("message", "source", 3);
-  test(e, "message", "source", 3,
-      "FormatException: message (at character 4)\nsource\n   ^\n");
-
-  e = new FormatException("message", "s1\nsource\ns2", 6);
-  test(e, "message", "s1\nsource\ns2", 6,
-      "FormatException: message (at line 2, character 4)\nsource\n   ^\n");
-
-  var longline = "watermelon cantaloupe " * 8 + "watermelon"; // Length > 160.
-  var longsource = (longline + "\n") * 25;
-  var line10 = (longline.length + 1) * 9;
-  e = new FormatException("message", longsource, line10);
-  test(
-      e,
-      "message",
-      longsource,
-      line10,
-      "FormatException: message (at line 10, character 1)\n"
-      "${longline.substring(0, 75)}...\n^\n");
-
-  e = new FormatException("message", longsource, line10 - 1);
-  test(
-      e,
-      "message",
-      longsource,
-      line10 - 1,
-      "FormatException: message (at line 9, "
-      "character ${longline.length + 1})\n"
-      "...${longline.substring(longline.length - 75)}\n"
-      "${' ' * 78}^\n");
-
-  var half = longline.length ~/ 2;
-  e = new FormatException("message", longsource, line10 + half);
-  test(
-      e,
-      "message",
-      longsource,
-      line10 + half,
-      "FormatException: message (at line 10, character ${half + 1})\n"
-      "...${longline.substring(half - 36, half + 36)}...\n"
-      "${' ' * 39}^\n");
-}