UnifiedDiffWriterTest.java

/*
 * Copyright 2019 java-diff-utils.
 *
 * 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.github.difflib.unifieddiff;

import static org.junit.jupiter.api.Assertions.assertEquals;

import com.github.difflib.DiffUtils;
import com.github.difflib.patch.Patch;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.junit.jupiter.api.Test;

/**
 *
 * @author Tobias Warneke (t.warneke@gmx.net)
 */
public class UnifiedDiffWriterTest {

		public UnifiedDiffWriterTest() {}

		@Test
		public void testWrite() throws URISyntaxException, IOException {
				String str = readFile(
								UnifiedDiffReaderTest.class
												.getResource("jsqlparser_patch_1.diff")
												.toURI(),
								Charset.defaultCharset());
				UnifiedDiff diff = UnifiedDiffReader.parseUnifiedDiff(new ByteArrayInputStream(str.getBytes()));

				StringWriter writer = new StringWriter();
				UnifiedDiffWriter.write(diff, f -> Collections.emptyList(), writer, 5);
				System.out.println(writer.toString());
		}

		/**
		 * Issue 47
		 */
		@Test
		public void testWriteWithNewFile() throws URISyntaxException, IOException {

				List<String> original = new ArrayList<>();
				List<String> revised = new ArrayList<>();

				revised.add("line1");
				revised.add("line2");

				Patch<String> patch = DiffUtils.diff(original, revised);
				UnifiedDiff diff = new UnifiedDiff();
				diff.addFile(UnifiedDiffFile.from(null, "revised", patch));

				StringWriter writer = new StringWriter();
				UnifiedDiffWriter.write(diff, f -> original, writer, 5);
				System.out.println(writer.toString());

				String[] lines = writer.toString().split("\\n");

				assertEquals("--- /dev/null", lines[0]);
				assertEquals("+++ revised", lines[1]);
				assertEquals("@@ -0,0 +1,2 @@", lines[2]);
		}

		static String readFile(URI path, Charset encoding) throws IOException {
				byte[] encoded = Files.readAllBytes(Paths.get(path));
				return new String(encoded, encoding);
		}
}