diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/MyersDiffTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/MyersDiffTest.java new file mode 100644 index 000000000..c91348ffe --- /dev/null +++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/MyersDiffTest.java @@ -0,0 +1,109 @@ +/* + * Copyright (C) 2009, Johannes E. Schindelin + * Copyright (C) 2009, Johannes Schindelin + * and other copyright owners as documented in the project's IP log. + * + * This program and the accompanying materials are made available + * under the terms of the Eclipse Distribution License v1.0 which + * accompanies this distribution, is reproduced below, and is + * available at http://www.eclipse.org/org/documents/edl-v10.php + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * - Neither the name of the Eclipse Foundation, Inc. nor the + * names of its contributors may be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND + * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +package org.eclipse.jgit.diff; + +import junit.framework.TestCase; + +public class MyersDiffTest extends TestCase { + public void testAtEnd() { + assertDiff("HELLO", "HELL", " -4,1 +4,0"); + } + + public void testAtStart() { + assertDiff("Git", "JGit", " -0,0 +0,1"); + } + + public void testSimple() { + assertDiff("HELLO WORLD", "LOW", + " -0,3 +0,0 -5,1 +2,0 -7,4 +3,0"); + // is ambiguous, could be this, too: + // " -0,2 +0,0 -3,1 +1,0 -5,1 +2,0 -7,4 +3,0" + } + + public void assertDiff(String a, String b, String edits) { + MyersDiff diff = new MyersDiff(toCharArray(a), toCharArray(b)); + assertEquals(edits, toString(diff.getEdits())); + } + + private static String toString(EditList list) { + StringBuilder builder = new StringBuilder(); + for (Edit e : list) + builder.append(" -" + e.beginA + + "," + (e.endA - e.beginA) + + " +" + e.beginB + "," + (e.endB - e.beginB)); + return builder.toString(); + } + + private static CharArray toCharArray(String s) { + return new CharArray(s); + } + + protected static String toString(Sequence seq, int begin, int end) { + CharArray a = (CharArray)seq; + return new String(a.array, begin, end - begin); + } + + protected static String toString(CharArray a, CharArray b, + int x, int k) { + return "(" + x + "," + (k + x) + + (x < 0 ? '<' : + (x >= a.array.length ? + '>' : a.array[x])) + + (k + x < 0 ? '<' : + (k + x >= b.array.length ? + '>' : b.array[k + x])) + + ")"; + } + + private static class CharArray implements Sequence { + char[] array; + public CharArray(String s) { array = s.toCharArray(); } + public int size() { return array.length; } + public boolean equals(int i, Sequence other, int j) { + CharArray o = (CharArray)other; + return array[i] == o.array[j]; + } + } +}