Strings recipes for the Dart Cookbook

recipes/test/core/strings/splitting_strings_test.dart

+library splitting_strings_test;
+
+import 'package:unittest/unittest.dart';
+
+void main() {
+  group('splitting a string', () {
+    var clef = '\u{1F3BC}';
+    var smileyFace = '\u263A';
+    var happy = 'I am $smileyFace';
+
+    group('using split(string)', () {
+      test('on code-unit boundary', () {
+        expect('Dart'.split(''), equals(['D', 'a', 'r', 't']));
+        expect(smileyFace.split('').length, equals(1));
+        expect(clef.split('').length, equals(2));
+      });
+      
+      test('on rune boundary', () {
+        expect(happy.runes.map((charCode) => new String.fromCharCode(charCode)).toList(), 
+            equals(['I', ' ', 'a', 'm', ' ', '\u263A']));
+      });
+    });
+      
+    group('using split(regExp)', () {
+      var nums = "2/7 3 4/5 3~/5";
+      var numsRegExp = new RegExp(r'(\s|/|~/)');
+      test('', () { 
+        expect(nums.split(numsRegExp), 
+            equals(['2', '7', '3', '4', '5', '3', '5']));
+      });
+    });
+    
+    group('using splitMapJoin(regExp)', () {
+      expect('Eats SHOOTS leaves'.splitMapJoin((new RegExp(r'SHOOTS')),
+          onMatch: (m) => '*${m.group(0).toLowerCase()}*',
+          onNonMatch: (n) => n.toUpperCase()
+      ), equals('EATS *shoots* LEAVES'));
+    });
+  });
+}