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sarinagurungjkozlowski
sarinagurung
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jkozlowski
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closes #9: Implement diffr.
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28 files changed

+346
-8
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28 files changed

+346
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lines changed

‎diff/src/main/java/diffr/diff/Diffr.java‎

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package diffr.diff;
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import com.google.common.collect.Lists;
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import diffr.suffixtree.SuffixTree;
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import diffr.suffixtree.SuffixTree.Matcher;
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import diffr.suffixtree.SuffixTrees;
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import diffr.util.instruction.CopyInstruction;
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import diffr.util.instruction.InsertInstruction;
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import diffr.util.instruction.Instruction;
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import java.util.List;
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import static com.google.common.base.Preconditions.checkNotNull;
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/**
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* Generates a list of {@link Instruction}s to transform original file into a new file.
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*
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* @author Sarina Gurung
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* @author Jakub D Kozlowski
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* @since 0.3
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*/
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public final class Diffr {
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private final List<String> originalFile;
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private final List<String> newFile;
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/**
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* Default constructor.
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*
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* @param originalFile original file to be transform.
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* @param newFile new file to transform {@code originalFile} to.
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*
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* @throws NullPointerException if any parameter is null.
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*/
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public Diffr(final List<String> originalFile, final List<String> newFile) {
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this.originalFile = checkNotNull(originalFile);
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this.newFile = checkNotNull(newFile);
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}
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/**
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* Gets the list of {@link Instruction}s to transform {@code originalFile} to {@code newFile}.
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*
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* @return list of {@link Instruction}s.
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*/
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public List<Instruction> diff() {
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final List<Instruction> instructions = Lists.newArrayList();
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final SuffixTree<String> suffixTree = SuffixTrees.newSuffixTree(this.originalFile);
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Matcher<String> matcher = suffixTree.matcher();
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for (final String newFileLine : newFile) {
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if (!matcher.matchNext(newFileLine).isMatched()) {
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if (!matcher.isRoot()) {
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instructions.add(new CopyInstruction(matcher.range()));
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}
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instructions.add(new InsertInstruction(newFileLine));
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matcher = suffixTree.matcher();
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}
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}
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if (!matcher.isRoot()) {
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instructions.add(new CopyInstruction(matcher.range()));
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}
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return instructions;
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}
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}

‎diff/src/main/java/diffr/diff/Main.java‎

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Original file line numberDiff line numberDiff line change
@@ -1,5 +1,14 @@
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package diffr.diff;
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import com.google.common.io.Files;
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import diffr.util.instruction.Instruction;
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import diffr.util.instruction.InstructionComposer;
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import java.io.File;
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import java.io.IOException;
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import java.nio.charset.Charset;
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import java.util.List;
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/**
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* Main entry point to diffr's DIFF tool.
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*
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* </p>
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*
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* @author Jakub D Kozlowski
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* @author Sarina Gurung
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* @since 0.1
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*/
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public final class Main {
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* Prints the usage of this tool.
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*/
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private static void printUsage() {
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System.out.println("diffr-diff <original-file> <new-file>");
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System.out.println("Usage: diffr <original-file> <new-file>");
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}
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/**
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* Runs the diff tool on two files.
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*
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* @param args arguments to this tool.
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*/
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public static void main(String... args) {
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public static void main(String... args) throws IOException {
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if (args.length != 2) {
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printUsage();
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System.exit(-1);
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}
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try {
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if (args.length != 2) {
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printUsage();
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System.exit(-1);
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}
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final File firstFile = new File(args[0]);
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final File secondFile = new File(args[1]);
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if (!firstFile.exists()) {
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System.err.println("File " + firstFile + " not found.");
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System.exit(-1);
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}
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System.exit(0);
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if (!secondFile.exists()) {
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System.err.println("File " + secondFile + " not found.");
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System.exit(-1);
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}
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final List<String> originalFile = Files.readLines(firstFile, Charset.defaultCharset());
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final List<String> newFile = Files.readLines(secondFile, Charset.defaultCharset());
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final List<Instruction> instructions = new Diffr(originalFile, newFile).diff();
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for (final Instruction instruction : instructions) {
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System.out.println(InstructionComposer.composeString(instruction));
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}
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System.out.flush();
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System.exit(0);
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}
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catch (final IOException io) {
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System.err.println("There was a problem reading the files: " + io);
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}
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}
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}

‎diff/src/test/java/diffr/diff/DiffrTest.java‎

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package diffr.diff;
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import com.google.common.collect.Lists;
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import com.google.common.io.Files;
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import com.google.common.io.LineProcessor;
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import com.google.common.io.Resources;
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import diffr.util.instruction.Instruction;
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import diffr.util.instruction.InstructionComposer;
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import diffr.util.instruction.InstructionParser;
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import org.testng.annotations.DataProvider;
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import org.testng.annotations.Test;
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import java.io.File;
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import java.io.IOException;
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import java.net.URISyntaxException;
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import java.nio.charset.Charset;
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import java.util.Collections;
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import java.util.Iterator;
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import java.util.List;
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import static org.hamcrest.MatcherAssert.assertThat;
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import static org.hamcrest.Matchers.is;
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/**
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* Tests {@link Diffr}.
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*
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* @author Sarina Gurung
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* @author Jakub D Kozlowski
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* @since 0.3
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*/
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public class DiffrTest {
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private static final String DEFAULT_PROVIDER = "default-provider";
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@DataProvider(name = "default-provider")
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public Object[][] getFiles() throws URISyntaxException, IOException {
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final List<Object[]> files = Lists.newArrayList();
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final File originalDir = new File(Resources.getResource("original").toURI());
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for (final File originalFile : originalDir.listFiles()) {
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final File newFile = new File(Resources.getResource("new/" + originalFile.getName()).toURI());
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final File patchFile = new File(Resources.getResource("patch/" + originalFile.getName()).toURI());
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files.add(new Object[]{
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Files.readLines(originalFile, Charset.defaultCharset()),
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Files.readLines(newFile, Charset.defaultCharset()),
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Files.readLines(patchFile, Charset.defaultCharset(), new LineProcessor<List<Instruction>>() {
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private List<Instruction> instructions = Lists.newArrayList();
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@Override
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public boolean processLine(String s) throws IOException {
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instructions.add(InstructionParser.parseInstruction(s).get());
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return true;
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}
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@Override
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public List<Instruction> getResult() {
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return instructions;
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}
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})
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});
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}
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return files.toArray(new Object[][]{});
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}
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@Test(expectedExceptions = NullPointerException.class)
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public void testConstructorNullOriginalFile() {
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new Diffr(null, Collections.EMPTY_LIST);
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}
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@Test(expectedExceptions = NullPointerException.class)
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public void testConstructorNullNewFile() {
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new Diffr(Collections.EMPTY_LIST, null);
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}
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@Test(dataProvider = DEFAULT_PROVIDER)
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public void testDiff(final List<String> originalFile,
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final List<String> newFile,
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final List<Instruction> patchFile)
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throws IOException, URISyntaxException {
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final Diffr d = new Diffr(originalFile, newFile);
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final Iterator<Instruction> actualInstructions = d.diff().iterator();
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for (final Instruction expected : patchFile) {
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final Instruction actual = actualInstructions.next();
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assertThat(InstructionComposer.composeString(actual),
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is(InstructionComposer.composeString(expected)));
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}
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}
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}

‎diff/src/test/resources/new/test1‎

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‎diff/src/test/resources/new/test2‎

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‎diff/src/test/resources/new/test3‎

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‎diff/src/test/resources/new/test4‎

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‎diff/src/test/resources/new/test5‎

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‎diff/src/test/resources/new/test6‎

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Hi

‎diff/src/test/resources/new/test7‎

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Hi

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