More String + elimination in tests

tests/standalone/io/file_invalid_arguments_test.dart

 // Copyright (c) 2012, 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("dart:io");
 
 class FileTest {
   static void testOpenInvalidArgs(name) {
     var file = new File(name);
     try {
@@ skipping 71 matching lines @@
       });
       return true;
     });
     readListFuture.then((bytes) {
       Expect.fail('read list invalid arguments');
     });
   }
 
   static void testWriteByteInvalidArgs(value) {
     String filename = getFilename("tests/vm/data/fixed_length_file");
-    var file = (new File(filename + "_out")).openSync(FileMode.WRITE);
+    var file = (new File(filename.concat("_out"))).openSync(FileMode.WRITE);

[siva, 2012/05/18 19:56:10]

Why do you use concat here and not:
new File("${filename}_out").openSync(FileMode.WRITE);

[hausner, 2012/05/18 21:03:46]

No particular reason, it just seemed more readable to me. If the code owners
don't like it, they can change it to use interpolation.

On 2012/05/18 19:56:10, asiva wrote:

     try {
       file.writeByteSync(value);
       Expect.fail('exception expected');
     } catch (var e) {
       Expect.isTrue(e is FileIOException);
       Expect.isTrue(e.toString().contains('Invalid argument'));
     }
 
     var writeByteFuture = file.writeByte(value);
     writeByteFuture.then((ignore) {
       Expect.fail('write byte invalid argument');
     });
     writeByteFuture.handleException((s) {
       Expect.isTrue(s is FileIOException);
       Expect.isTrue(s.toString().contains('Invalid argument'));
       file.close();
       return true;
     });
   }
 
   static void testWriteListInvalidArgs(buffer, offset, bytes) {
     String filename = getFilename("tests/vm/data/fixed_length_file");
-    var file = (new File(filename + "_out")).openSync(FileMode.WRITE);
+    var file = (new File(filename.concat("_out"))).openSync(FileMode.WRITE);
     try {
       file.writeListSync(buffer, offset, bytes);
       Expect.fail('exception expected');
     } catch (var e) {
       Expect.isTrue(e is FileIOException);
       Expect.isTrue(e.toString().contains('Invalid arguments'));
     }
 
     var writeListFuture = file.writeList(buffer, offset, bytes);
     writeListFuture.then((ignore) {
       Expect.fail('write list invalid argument');
     });
     writeListFuture.handleException((s) {
       Expect.isTrue(s is FileIOException);
       Expect.isTrue(s.toString().contains('Invalid arguments'));
       file.close();
       return true;
     });
   }
 
   static void testWriteStringInvalidArgs(string) {
     String filename = getFilename("tests/vm/data/fixed_length_file");
-    var file = new File(filename + "_out");
+    var file = new File(filename.concat("_out"));
     file.openSync(FileMode.WRITE);
     try {
       file.writeString(string);
       Expect.fail('exception expected');
     } catch (var e) {
       Expect.isTrue(e is FileIOException);
       Expect.isTrue(e.toString().contains('writeString failed'));
     }
 
     var errors = 0;
@@ skipping 25 matching lines @@
     fullPathFuture.handleException((e) {
       Expect.isTrue(e is IllegalArgumentException);
       return true;
     });
     fullPathFuture.then((path) {
       Expect.fail('full path invalid argument');
     });
   }
 
   static String getFilename(String path) =>
-      new File(path).existsSync() ? path : 'runtime/' + path;
+      new File(path).existsSync() ? path : 'runtime/$path';
 }
 
 main() {
   FileTest.testOpenInvalidArgs(0);
   FileTest.testExistsInvalidArgs(0);
   FileTest.testCreateInvalidArgs(0);
   FileTest.testReadListInvalidArgs(12, 0, 1);
   FileTest.testReadListInvalidArgs(new List(10), '0', 1);
   FileTest.testReadListInvalidArgs(new List(10), 0, '1');
   FileTest.testWriteByteInvalidArgs('asdf');
   FileTest.testWriteListInvalidArgs(12, 0, 1);
   FileTest.testWriteListInvalidArgs(new List(10), '0', 1);
   FileTest.testWriteListInvalidArgs(new List(10), 0, '1');
   FileTest.testFullPathInvalidArgs(12);
 }