Optimize one-byte string's toUpperCase.

tests/corelib/string_case_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.
 
 import "package:expect/expect.dart";
 
-class StringCaseTest {
-
-  static testMain() {
-    testLowerUpper();
-  }
-
-  static testLowerUpper() {
-    var a = "Stop! Smell the Roses.";
-    var allLower = "stop! smell the roses.";
-    var allUpper = "STOP! SMELL THE ROSES.";
-    Expect.equals(allUpper, a.toUpperCase());
-    Expect.equals(allLower, a.toLowerCase());
-  }
+main() {
+  testLowerUpper();
+  testSpecialCases();
 }
 
-main() {
-  StringCaseTest.testMain();
+void testLowerUpper() {
+  var a = "Stop! Smell the Roses.";
+  var allLower = "stop! smell the roses.";
+  var allUpper = "STOP! SMELL THE ROSES.";
+  Expect.equals(allUpper, a.toUpperCase());
+  Expect.equals(allLower, a.toLowerCase());
 }
+
+void testSpecialCases() {
+  // Letters in Latin-1 where the upper case is not in Latin-1.
+
+  // Small letter y diaresis.
+  Expect.equals("\u0178", "\xff".toUpperCase());              /// 03: ok
+  Expect.equals("\xff", "\xff".toLowerCase());
+  Expect.equals("\xff", "\xff".toUpperCase().toLowerCase());  /// 03: continued
+  // German sharp s. Upper case variant is "SS".
+  Expect.equals("SS", "\xdf".toUpperCase());                /// 01: ok
+  Expect.equals("\xdf", "\xdf".toLowerCase());
+  Expect.equals("ss", "\xdf".toUpperCase().toLowerCase());  /// 01: continued
+  // Micro sign (not same as lower-case Greek letter mu, U+03BC).
+  Expect.equals("\u039c", "\xb5".toUpperCase());                /// 02: ok
+  Expect.equals("\xb5", "\xb5".toLowerCase());
+  Expect.equals("\u03Bc", "\xb5".toUpperCase().toLowerCase());  /// 02: continued

[Anders Johnsen, 2014/04/07 11:43:43]

Long line.

[Lasse Reichstein Nielsen, 2014/04/07 12:12:13]

Done.

+  // Zero.

[Anders Johnsen, 2014/04/07 11:43:43]

Do you have a test that would have spotted the 0xff issue? For lower-case, we
have a one-byte-string vs two-byte-string test for all characters. Can we do
that here as well?

[Lasse Reichstein Nielsen, 2014/04/07 12:12:13]

It should be detected by the "\xff".toUpperCase() case alone.
That's why I added the "\x00" test. 

I'll add a few more tests, just for good measure.

+  Expect.equals("\x00", "\x00".toLowerCase());
+  Expect.equals("\x00", "\x00".toUpperCase());
+}