1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package libcore.java.lang; 18 19 import java.util.Arrays; 20 21 public class StringBuilderTest extends junit.framework.TestCase { 22 // See https://code.google.com/p/android/issues/detail?id=60639 23 public void test_deleteChatAt_lastRange() { 24 StringBuilder sb = new StringBuilder("oarFish_"); 25 sb.append('a'); 26 String oarFishA = sb.toString(); 27 28 sb.deleteCharAt(sb.length() - 1); 29 sb.append('b'); 30 String oarFishB = sb.toString(); 31 32 assertEquals("oarFish_a", oarFishA); 33 assertEquals("oarFish_b", oarFishB); 34 } 35 36 // See https://code.google.com/p/android/issues/detail?id=60639 37 public void test_deleteCharAt_lastChar() { 38 StringBuilder sb = new StringBuilder(); 39 sb.append('a'); 40 String a = sb.toString(); 41 42 sb.deleteCharAt(0); 43 sb.append('b'); 44 String b = sb.toString(); 45 46 assertEquals("a", a); 47 assertEquals("b", b); 48 } 49 50 // See https://code.google.com/p/android/issues/detail?id=60639 51 public void test_delete_endsAtLastChar() { 52 StringBuilder sb = new StringBuilder("newGuineaSinging"); 53 sb.append("Dog"); 54 String dog = sb.toString(); 55 56 sb.delete(sb.length() - 3, sb.length()); 57 sb.append("Cat"); 58 String cat = sb.toString(); 59 60 // NOTE: It's important that these asserts stay at the end of this test. 61 // We're trying to make sure that replacing chars in the builder does not 62 // change strings that have already been returned from it. 63 assertEquals("newGuineaSingingDog", dog); 64 assertEquals("newGuineaSingingCat", cat); 65 } 66 67 public void test_deleteCharAt_boundsChecks() { 68 StringBuilder sb = new StringBuilder("yeti"); 69 70 try { 71 sb.deleteCharAt(sb.length()); 72 fail(); 73 } catch (StringIndexOutOfBoundsException expected) { 74 } 75 76 try { 77 sb.deleteCharAt(-1); 78 fail(); 79 } catch (StringIndexOutOfBoundsException expected) { 80 } 81 } 82 83 public void test_delete_boundsChecks() throws Exception { 84 StringBuilder sb = new StringBuilder("yeti"); 85 86 // The cases below ahould not throw (even though they are clearly invalid 87 // ranges), because we promise not to throw if start == count as long as 88 // end >= start. 89 sb.delete(sb.length(), sb.length() + 2); 90 sb.delete(sb.length(), sb.length()); 91 92 sb.delete(2, 2); 93 assertEquals("yeti", sb.toString()); 94 95 // We must throw if start > count.... 96 try { 97 sb.delete(sb.length() + 2, sb.length() + 3); 98 fail(); 99 } catch (StringIndexOutOfBoundsException expected) { 100 } 101 102 // ... even if the length of the range is 0. 103 try { 104 sb.delete(sb.length() + 2, sb.length() + 2); 105 fail(); 106 } catch (StringIndexOutOfBoundsException expected) { 107 } 108 109 // Must throw if start < 0. 110 try { 111 sb.delete(-1, sb.length() -1); 112 fail(); 113 } catch (StringIndexOutOfBoundsException expected) { 114 } 115 116 // A few commonly used specializations: sb.delete(0, 0) on an empty 117 // builder is a particularly common pattern. 118 StringBuilder sb2 = new StringBuilder(); 119 sb2.delete(0, sb2.length()); 120 sb2.delete(0, 12); 121 } 122 123 // We shouldn't throw if the end index is > count, we should clamp it 124 // instead. 125 public void test_delete_clampsEnd() throws Exception { 126 StringBuilder sb = new StringBuilder("mogwai"); 127 128 sb.delete(sb.length() - 1 , sb.length() + 2); 129 assertEquals("mogwa", sb.toString()); 130 131 sb.delete(sb.length() - 1, sb.length()); 132 assertEquals("mogw", sb.toString()); 133 } 134 135 public void testChars() { 136 StringBuilder s = new StringBuilder("Hello\n\tworld"); 137 int[] expected = new int[s.length()]; 138 for (int i = 0; i < s.length(); ++i) { 139 expected[i] = (int) s.charAt(i); 140 } 141 assertTrue(Arrays.equals(expected, s.chars().toArray())); 142 143 // Surrogate code point 144 char high = '\uD83D', low = '\uDE02'; 145 StringBuilder surrogateCP = new StringBuilder().append(new char[]{high, low, low}); 146 assertTrue(Arrays.equals(new int[]{high, low, low}, surrogateCP.chars().toArray())); 147 } 148 149 public void testCodePoints() { 150 StringBuilder s = new StringBuilder("Hello\n\tworld"); 151 int[] expected = new int[s.length()]; 152 for (int i = 0; i < s.length(); ++i) { 153 expected[i] = (int) s.charAt(i); 154 } 155 assertTrue(Arrays.equals(expected, s.codePoints().toArray())); 156 157 // Surrogate code point 158 char high = '\uD83D', low = '\uDE02'; 159 StringBuilder surrogateCP = new StringBuilder().append(new char[]{high, low, low, '0'}); 160 assertEquals(Character.toCodePoint(high, low), surrogateCP.codePoints().toArray()[0]); 161 assertEquals((int) low, surrogateCP.codePoints().toArray()[1]); // Unmatched surrogate. 162 assertEquals((int) '0', surrogateCP.codePoints().toArray()[2]); 163 } 164 } 165
