/*
* Copyright (C) 2010 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.base;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.testing.NullPointerTester;
import junit.framework.TestCase;
/**
* Unit test for {@link Strings}.
*
* @author Kevin Bourrillion
*/
@GwtCompatible(emulated = true)
public class StringsTest extends TestCase {
public void testNullToEmpty() {
assertEquals("", Strings.nullToEmpty(null));
assertEquals("", Strings.nullToEmpty(""));
assertEquals("a", Strings.nullToEmpty("a"));
}
public void testEmptyToNull() {
assertNull(Strings.emptyToNull(null));
assertNull(Strings.emptyToNull(""));
assertEquals("a", Strings.emptyToNull("a"));
}
public void testIsNullOrEmpty() {
assertTrue(Strings.isNullOrEmpty(null));
assertTrue(Strings.isNullOrEmpty(""));
assertFalse(Strings.isNullOrEmpty("a"));
}
public void testPadStart_noPadding() {
assertSame("", Strings.padStart("", 0, '-'));
assertSame("x", Strings.padStart("x", 0, '-'));
assertSame("x", Strings.padStart("x", 1, '-'));
assertSame("xx", Strings.padStart("xx", 0, '-'));
assertSame("xx", Strings.padStart("xx", 2, '-'));
}
public void testPadStart_somePadding() {
assertEquals("-", Strings.padStart("", 1, '-'));
assertEquals("--", Strings.padStart("", 2, '-'));
assertEquals("-x", Strings.padStart("x", 2, '-'));
assertEquals("--x", Strings.padStart("x", 3, '-'));
assertEquals("-xx", Strings.padStart("xx", 3, '-'));
}
public void testPadStart_negativeMinLength() {
assertSame("x", Strings.padStart("x", -1, '-'));
}
// TODO: could remove if we got NPT working in GWT somehow
public void testPadStart_null() {
try {
Strings.padStart(null, 5, '0');
fail();
} catch (NullPointerException expected) {
}
}
public void testPadEnd_noPadding() {
assertSame("", Strings.padEnd("", 0, '-'));
assertSame("x", Strings.padEnd("x", 0, '-'));
assertSame("x", Strings.padEnd("x", 1, '-'));
assertSame("xx", Strings.padEnd("xx", 0, '-'));
assertSame("xx", Strings.padEnd("xx", 2, '-'));
}
public void testPadEnd_somePadding() {
assertEquals("-", Strings.padEnd("", 1, '-'));
assertEquals("--", Strings.padEnd("", 2, '-'));
assertEquals("x-", Strings.padEnd("x", 2, '-'));
assertEquals("x--", Strings.padEnd("x", 3, '-'));
assertEquals("xx-", Strings.padEnd("xx", 3, '-'));
}
public void testPadEnd_negativeMinLength() {
assertSame("x", Strings.padEnd("x", -1, '-'));
}
// TODO: could remove if we got NPT working in GWT somehow
public void testPadEnd_null() {
try {
Strings.padEnd(null, 5, '0');
fail();
} catch (NullPointerException expected) {
}
}
public void testRepeat() {
String input = "20";
assertEquals("", Strings.repeat(input, 0));
assertEquals("20", Strings.repeat(input, 1));
assertEquals("2020", Strings.repeat(input, 2));
assertEquals("202020", Strings.repeat(input, 3));
assertEquals("", Strings.repeat("", 4));
for (int i = 0; i < 100; ++i) {
assertEquals(2 * i, Strings.repeat(input, i).length());
}
try {
Strings.repeat("x", -1);
fail();
} catch (IllegalArgumentException expected) {
}
try {
// Massive string
Strings.repeat("12345678", (1 << 30) + 3);
fail();
} catch (ArrayIndexOutOfBoundsException expected) {
}
}
// TODO: could remove if we got NPT working in GWT somehow
public void testRepeat_null() {
try {
Strings.repeat(null, 5);
fail();
} catch (NullPointerException expected) {
}
}
public void testCommonPrefix() {
assertEquals("", Strings.commonPrefix("", ""));
assertEquals("", Strings.commonPrefix("abc", ""));
assertEquals("", Strings.commonPrefix("", "abc"));
assertEquals("", Strings.commonPrefix("abcde", "xyz"));
assertEquals("", Strings.commonPrefix("xyz", "abcde"));
assertEquals("", Strings.commonPrefix("xyz", "abcxyz"));
assertEquals("a", Strings.commonPrefix("abc", "aaaaa"));
assertEquals("aa", Strings.commonPrefix("aa", "aaaaa"));
assertEquals("abc",
Strings.commonPrefix(new StringBuffer("abcdef"), "abcxyz"));
// Identical valid surrogate pairs.
assertEquals("abc\uD8AB\uDCAB",
Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uDCABxyz"));
// Differing valid surrogate pairs.
assertEquals("abc",
Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uDCACxyz"));
// One invalid pair.
assertEquals("abc",
Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uD8ABxyz"));
// Two identical invalid pairs.
assertEquals("abc\uD8AB\uD8AC",
Strings.commonPrefix("abc\uD8AB\uD8ACdef", "abc\uD8AB\uD8ACxyz"));
// Two differing invalid pairs.
assertEquals("abc\uD8AB",
Strings.commonPrefix("abc\uD8AB\uD8ABdef", "abc\uD8AB\uD8ACxyz"));
// One orphan high surrogate.
assertEquals("", Strings.commonPrefix("\uD8AB\uDCAB", "\uD8AB"));
// Two orphan high surrogates.
assertEquals("\uD8AB", Strings.commonPrefix("\uD8AB", "\uD8AB"));
}
public void testCommonSuffix() {
assertEquals("", Strings.commonSuffix("", ""));
assertEquals("", Strings.commonSuffix("abc", ""));
assertEquals("", Strings.commonSuffix("", "abc"));
assertEquals("", Strings.commonSuffix("abcde", "xyz"));
assertEquals("", Strings.commonSuffix("xyz", "abcde"));
assertEquals("", Strings.commonSuffix("xyz", "xyzabc"));
assertEquals("c", Strings.commonSuffix("abc", "ccccc"));
assertEquals("aa", Strings.commonSuffix("aa", "aaaaa"));
assertEquals("abc",
Strings.commonSuffix(new StringBuffer("xyzabc"), "xxxabc"));
// Identical valid surrogate pairs.
assertEquals("\uD8AB\uDCABdef",
Strings.commonSuffix("abc\uD8AB\uDCABdef", "xyz\uD8AB\uDCABdef"));
// Differing valid surrogate pairs.
assertEquals("def",
Strings.commonSuffix("abc\uD8AB\uDCABdef", "abc\uD8AC\uDCABdef"));
// One invalid pair.
assertEquals("def",
Strings.commonSuffix("abc\uD8AB\uDCABdef", "xyz\uDCAB\uDCABdef"));
// Two identical invalid pairs.
assertEquals("\uD8AB\uD8ABdef",
Strings.commonSuffix("abc\uD8AB\uD8ABdef", "xyz\uD8AB\uD8ABdef"));
// Two differing invalid pairs.
assertEquals("\uDCABdef",
Strings.commonSuffix("abc\uDCAB\uDCABdef", "abc\uDCAC\uDCABdef"));
// One orphan low surrogate.
assertEquals("", Strings.commonSuffix("x\uD8AB\uDCAB", "\uDCAB"));
// Two orphan low surrogates.
assertEquals("\uDCAB", Strings.commonSuffix("\uDCAB", "\uDCAB"));
}
public void testValidSurrogatePairAt() {
assertTrue(Strings.validSurrogatePairAt("\uD8AB\uDCAB", 0));
assertTrue(Strings.validSurrogatePairAt("abc\uD8AB\uDCAB", 3));
assertTrue(Strings.validSurrogatePairAt("abc\uD8AB\uDCABxyz", 3));
assertFalse(Strings.validSurrogatePairAt("\uD8AB\uD8AB", 0));
assertFalse(Strings.validSurrogatePairAt("\uDCAB\uDCAB", 0));
assertFalse(Strings.validSurrogatePairAt("\uD8AB\uDCAB", -1));
assertFalse(Strings.validSurrogatePairAt("\uD8AB\uDCAB", 1));
assertFalse(Strings.validSurrogatePairAt("\uD8AB\uDCAB", -2));
assertFalse(Strings.validSurrogatePairAt("\uD8AB\uDCAB", 2));
assertFalse(Strings.validSurrogatePairAt("x\uDCAB", 0));
assertFalse(Strings.validSurrogatePairAt("\uD8ABx", 0));
}
@GwtIncompatible("NullPointerTester")
public void testNullPointers() {
NullPointerTester tester = new NullPointerTester();
tester.testAllPublicStaticMethods(Strings.class);
}
}