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/*
* SonarQube, open source software quality management tool.
* Copyright (C) 2008-2014 SonarSource
* mailto:contact AT sonarsource DOT com
*
* SonarQube is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* SonarQube is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.duplications.java;
import com.google.common.base.Joiner;
import org.junit.Test;
import org.sonar.duplications.block.Block;
import org.sonar.duplications.block.BlockChunker;
import org.sonar.duplications.detector.suffixtree.SuffixTreeCloneDetectionAlgorithm;
import org.sonar.duplications.index.CloneGroup;
import org.sonar.duplications.index.CloneIndex;
import org.sonar.duplications.index.ClonePart;
import org.sonar.duplications.index.MemoryCloneIndex;
import org.sonar.duplications.statement.Statement;
import org.sonar.duplications.statement.StatementChunker;
import org.sonar.duplications.token.TokenChunker;
import java.util.Collection;
import java.util.List;
import static org.hamcrest.Matchers.is;
import static org.junit.Assert.assertThat;
/**
* From <a href="http://research.cs.queensu.ca/TechReports/Reports/2007-541.pdf">A Survey on Software Clone Detection Research (2007 year)</a>:
* <ul>
* <li>Type 1: Identical code fragments except for variations in whitespace (may be also variations in layout) and comments.
* Type 1 is widely know as Exact clones.</li>
* <li>Type 2: Structurally/syntactically identical fragments except for variations in identifiers, literals, types, layout and comments.
* The reserved words and the sentence structures are essentially the same.</li>
* <li>Type 3: Copied fragments with further modifications. Statements can be changed,
* added and/or deleted in addition to variations in identifiers, literals, types, layout
* and comments.</li>
* </ul>
*/
public class JavaDuplicationsFunctionalTest {
@Test
public void type1() {
String fragment0 = source(
"if (a >= b) {",
" c = d + b; // Comment1",
" d = d + 1;}",
"else",
" c = d - a; // Comment2");
String fragment1 = source(
"if (a>=b) {",
" // Comment1",
" c=d+b;",
" d=d+1;",
"} else // Comment2",
" c=d-a;");
List<CloneGroup> duplications = detect2(fragment0, fragment1);
assertThat(duplications.size(), is(1));
ClonePart part = duplications.get(0).getOriginPart();
assertThat(part.getStartLine(), is(1));
assertThat(part.getEndLine(), is(5));
}
/**
* Supports only subset of Type 2.
*
* @see #type2
* @see #literalsNormalization()
*/
@Test
public void type2_literals() {
String fragment0 = source(
"if (a >= b) {",
" c = b + 1; // Comment1",
" d = '1';}",
"else",
" c = d - a; // Comment2");
String fragment1 = source(
"if (a >= b) {",
" c = b + 2; // Comment1",
" d = '2';}",
"else",
" c = d - a; // Comment2");
List<CloneGroup> duplications = detect2(fragment0, fragment1);
assertThat(duplications.size(), is(1));
ClonePart part = duplications.get(0).getOriginPart();
assertThat(part.getStartLine(), is(1));
assertThat(part.getEndLine(), is(5));
}
@Test
public void type2() {
String fragment0 = source(
"if (a >= b) {",
" c = d + b; // Comment1",
" d = d + 1;}",
"else",
" c = d - a; // Comment2");
String fragment1 = source(
"if (m >= n) {",
" // Comment3",
" y = x + n; // Comment1",
" x = x + 5;}",
"else",
" y = x - m; // Comment2");
List<CloneGroup> duplications = detect2(fragment0, fragment1);
assertThat(duplications.size(), is(0));
}
/**
* Does not support Type 3, however able to detect inner parts.
*/
@Test
public void type3() {
String fragment0 = source(
"public int getSoLinger() throws SocketException {",
" Object o = impl.getOption( SocketOptions.SO_LINGER);",
" if (o instanceof Integer) {",
" return((Integer) o).intValue();",
" }",
" else return -1;",
"}");
String fragment1 = source(
"public synchronized int getSoTimeout() throws SocketException {",
" Object o = impl.getOption( SocketOptions.SO_TIMEOUT);",
" if (o instanceof Integer) {",
" return((Integer) o).intValue();",
" }",
" else return -0;",
"}"
);
List<CloneGroup> duplications = detect2(fragment0, fragment1);
assertThat(duplications.size(), is(1));
ClonePart part = duplications.get(0).getOriginPart();
assertThat(part.getStartLine(), is(3));
assertThat(part.getEndLine(), is(6));
}
private String source(String... lines) {
return Joiner.on('\n').join(lines);
}
private static List<CloneGroup> detect2(String... fragments) {
MemoryCloneIndex index = new MemoryCloneIndex();
for (int i = 0; i < fragments.length; i++) {
addToIndex(index, "fragment" + i, fragments[i]);
}
return detect(index, index.getByResourceId("fragment0"));
}
private static void addToIndex(CloneIndex index, String resourceId, String sourceCode) {
List<Statement> statements = STATEMENT_CHUNKER.chunk(TOKEN_CHUNKER.chunk(sourceCode));
BlockChunker blockChunker = new BlockChunker(2);
List<Block> blocks = blockChunker.chunk(resourceId, statements);
for (Block block : blocks) {
index.insert(block);
}
}
private static List<CloneGroup> detect(CloneIndex index, Collection<Block> blocks) {
return SuffixTreeCloneDetectionAlgorithm.detect(index, blocks);
}
private static final int BLOCK_SIZE = 1;
private static TokenChunker TOKEN_CHUNKER = JavaTokenProducer.build();
private static StatementChunker STATEMENT_CHUNKER = JavaStatementBuilder.build();
private static BlockChunker BLOCK_CHUNKER = new BlockChunker(BLOCK_SIZE);
private List<CloneGroup> detect(String... lines) {
String sourceCode = Joiner.on('\n').join(lines);
MemoryCloneIndex index = new MemoryCloneIndex();
List<Statement> statements = STATEMENT_CHUNKER.chunk(TOKEN_CHUNKER.chunk(sourceCode));
List<Block> blocks = BLOCK_CHUNKER.chunk("resourceId", statements);
for (Block block : blocks) {
index.insert(block);
}
return detect(index, blocks);
}
/**
* See SONAR-2837
*/
@Test
public void initializationOfMultidimensionalArray() {
List<CloneGroup> duplications = detect("int[][] idx = new int[][] { { 1, 2 }, { 3, 4 } };");
assertThat(duplications.size(), is(0));
}
/**
* See SONAR-2782
*/
@Test
public void chainOfCases() {
List<CloneGroup> duplications = detect(
"switch (a) {",
" case 'a': case 'b': case 'c':",
" doSomething();",
" case 'd': case 'e': case 'f':",
" doSomethingElse();",
"}");
assertThat(duplications.size(), is(0));
}
@Test
public void literalsNormalization() {
List<CloneGroup> duplications = detect(
"String s = \"abc\";",
"String s = \"def\";");
assertThat(duplications.size(), is(1));
duplications = detect(
"int i = 1;",
"int i = 2;");
assertThat(duplications.size(), is(1));
}
}
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