| /* |
| * Copyright (C) 2010, Google Inc. and others |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Distribution License v. 1.0 which is available at |
| * https://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| */ |
| |
| package org.eclipse.jgit.diff; |
| |
| import static org.junit.Assert.assertEquals; |
| |
| import org.junit.Test; |
| |
| |
| public class HistogramDiffTest extends AbstractDiffTestCase { |
| @Override |
| protected HistogramDiff algorithm() { |
| HistogramDiff hd = new HistogramDiff(); |
| hd.setFallbackAlgorithm(null); |
| return hd; |
| } |
| |
| @Test |
| public void testEdit_NoUniqueMiddleSide_FlipBlocks() { |
| EditList r = diff(t("aRRSSz"), t("aSSRRz")); |
| assertEquals(2, r.size()); |
| assertEquals(new Edit(1, 3, 1, 1), r.get(0)); // DELETE "RR" |
| assertEquals(new Edit(5, 5, 3, 5), r.get(1)); // INSERT "RR |
| } |
| |
| @Test |
| public void testEdit_NoUniqueMiddleSide_Insert2() { |
| EditList r = diff(t("aRSz"), t("aRRSSz")); |
| assertEquals(1, r.size()); |
| assertEquals(new Edit(2, 2, 2, 4), r.get(0)); |
| } |
| |
| @Test |
| public void testEdit_NoUniqueMiddleSide_FlipAndExpand() { |
| EditList r = diff(t("aRSz"), t("aSSRRz")); |
| assertEquals(2, r.size()); |
| assertEquals(new Edit(1, 2, 1, 1), r.get(0)); // DELETE "R" |
| assertEquals(new Edit(3, 3, 2, 5), r.get(1)); // INSERT "SRR" |
| } |
| |
| @Test |
| public void testEdit_LcsContainsUnique() { |
| EditList r = diff(t("nqnjrnjsnm"), t("AnqnjrnjsnjTnmZ")); |
| assertEquals(new Edit(0, 0, 0, 1), r.get(0)); // INSERT "A"; |
| assertEquals(new Edit(9, 9, 10, 13), r.get(1)); // INSERT "jTn"; |
| assertEquals(new Edit(10, 10, 14, 15), r.get(2)); // INSERT "Z"; |
| assertEquals(3, r.size()); |
| } |
| |
| @Test |
| public void testExceedsChainLength_DuringScanOfA() { |
| HistogramDiff hd = new HistogramDiff(); |
| hd.setFallbackAlgorithm(null); |
| hd.setMaxChainLength(3); |
| |
| SequenceComparator<RawText> cmp = new SequenceComparator<RawText>() { |
| @Override |
| public boolean equals(RawText a, int ai, RawText b, int bi) { |
| return RawTextComparator.DEFAULT.equals(a, ai, b, bi); |
| } |
| |
| @Override |
| public int hash(RawText a, int ai) { |
| return 1; |
| } |
| }; |
| |
| EditList r = hd.diff(cmp, t("RabS"), t("QabT")); |
| assertEquals(1, r.size()); |
| assertEquals(new Edit(0, 4, 0, 4), r.get(0)); |
| } |
| |
| @Test |
| public void testExceedsChainLength_DuringScanOfB() { |
| HistogramDiff hd = new HistogramDiff(); |
| hd.setFallbackAlgorithm(null); |
| hd.setMaxChainLength(1); |
| |
| EditList r = hd.diff(RawTextComparator.DEFAULT, t("RaaS"), t("QaaT")); |
| assertEquals(1, r.size()); |
| assertEquals(new Edit(0, 4, 0, 4), r.get(0)); |
| } |
| |
| @Test |
| public void testFallbackToMyersDiff() { |
| HistogramDiff hd = new HistogramDiff(); |
| hd.setMaxChainLength(4); |
| |
| RawTextComparator cmp = RawTextComparator.DEFAULT; |
| RawText ac = t("bbbbb"); |
| RawText bc = t("AbCbDbEFbZ"); |
| EditList r; |
| |
| // Without fallback our results are limited due to collisions. |
| hd.setFallbackAlgorithm(null); |
| r = hd.diff(cmp, ac, bc); |
| assertEquals(1, r.size()); |
| |
| // Results go up when we add a fallback for the high collision regions. |
| hd.setFallbackAlgorithm(MyersDiff.INSTANCE); |
| r = hd.diff(cmp, ac, bc); |
| assertEquals(5, r.size()); |
| } |
| } |