/*
    * Copyright (C) 2010, Christian Halstrick <christian.halstrick@sap.com>
    * 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
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   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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  package org.eclipse.jgit.api;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.Iterator;
  
  import org.eclipse.jgit.api.CherryPickResult.CherryPickStatus;
  import org.eclipse.jgit.api.ResetCommand.ResetType;
  import org.eclipse.jgit.api.errors.GitAPIException;
  import org.eclipse.jgit.api.errors.JGitInternalException;
  import org.eclipse.jgit.api.errors.MultipleParentsNotAllowedException;
  import org.eclipse.jgit.dircache.DirCache;
  import org.eclipse.jgit.junit.RepositoryTestCase;
  import org.eclipse.jgit.lib.ConfigConstants;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.FileMode;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.ReflogReader;
  import org.eclipse.jgit.lib.RepositoryState;
  import org.eclipse.jgit.merge.ResolveMerger.MergeFailureReason;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.junit.Test;
  
  /**
   * Test cherry-pick command
   */
  public class CherryPickCommandTest extends RepositoryTestCase {
  	@Test
  	public void testCherryPick() throws IOException, JGitInternalException,
  			GitAPIException {
  		doTestCherryPick(false);
  	}
  
  	@Test
  	public void testCherryPickNoCommit() throws IOException,
  			JGitInternalException, GitAPIException {
  		doTestCherryPick(true);
  	}
  
  	private void doTestCherryPick(boolean noCommit) throws IOException,
  			JGitInternalException,
  			GitAPIException {
  		try (Git git = new Git(db)) {
  			writeTrashFile("a", "first line\nsec. line\nthird line\n");
  			git.add().addFilepattern("a").call();
  			RevCommit firstCommit = git.commit().setMessage("create a").call();
  
  			writeTrashFile("b", "content\n");
  			git.add().addFilepattern("b").call();
  			git.commit().setMessage("create b").call();
  
 			writeTrashFile("a", "first line\nsec. line\nthird line\nfourth line\n");
 			git.add().addFilepattern("a").call();
 			git.commit().setMessage("enlarged a").call();
 
 			writeTrashFile("a",
 					"first line\nsecond line\nthird line\nfourth line\n");
 			git.add().addFilepattern("a").call();
 			RevCommit fixingA = git.commit().setMessage("fixed a").call();
 
 			git.branchCreate().setName("side").setStartPoint(firstCommit).call();
 			checkoutBranch("refs/heads/side");
 
 			writeTrashFile("a", "first line\nsec. line\nthird line\nfeature++\n");
 			git.add().addFilepattern("a").call();
 			git.commit().setMessage("enhanced a").call();
 
 			CherryPickResult pickResult = git.cherryPick().include(fixingA)
 					.setNoCommit(noCommit).call();
 
 			assertEquals(CherryPickStatus.OK, pickResult.getStatus());
 			assertFalse(new File(db.getWorkTree(), "b").exists());
 			checkFile(new File(db.getWorkTree(), "a"),
 					"first line\nsecond line\nthird line\nfeature++\n");
 			Iterator<RevCommit> history = git.log().call().iterator();
 			if (!noCommit)
 				assertEquals("fixed a", history.next().getFullMessage());
 			assertEquals("enhanced a", history.next().getFullMessage());
 			assertEquals("create a", history.next().getFullMessage());
 			assertFalse(history.hasNext());
 		}
 	}
 
     @Test
     public void testSequentialCherryPick() throws IOException, JGitInternalException,
             GitAPIException {
         try (Git git = new Git(db)) {
 	        writeTrashFile("a", "first line\nsec. line\nthird line\n");
 	        git.add().addFilepattern("a").call();
 	        RevCommit firstCommit = git.commit().setMessage("create a").call();
 
 	        writeTrashFile("a", "first line\nsec. line\nthird line\nfourth line\n");
 	        git.add().addFilepattern("a").call();
 	        RevCommit enlargingA = git.commit().setMessage("enlarged a").call();
 
 	        writeTrashFile("a",
 	                "first line\nsecond line\nthird line\nfourth line\n");
 	        git.add().addFilepattern("a").call();
 	        RevCommit fixingA = git.commit().setMessage("fixed a").call();
 
 	        git.branchCreate().setName("side").setStartPoint(firstCommit).call();
 	        checkoutBranch("refs/heads/side");
 
 	        writeTrashFile("b", "nothing to do with a");
 	        git.add().addFilepattern("b").call();
 	        git.commit().setMessage("create b").call();
 
 	        CherryPickResult result = git.cherryPick().include(enlargingA).include(fixingA).call();
 	        assertEquals(CherryPickResult.CherryPickStatus.OK, result.getStatus());
 
 	        Iterator<RevCommit> history = git.log().call().iterator();
 	        assertEquals("fixed a", history.next().getFullMessage());
 	        assertEquals("enlarged a", history.next().getFullMessage());
 	        assertEquals("create b", history.next().getFullMessage());
 	        assertEquals("create a", history.next().getFullMessage());
 	        assertFalse(history.hasNext());
         }
     }
 
 	@Test
 	public void testCherryPickDirtyIndex() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			// modify and add file a
 			writeTrashFile("a", "a(modified)");
 			git.add().addFilepattern("a").call();
 			// do not commit
 
 			doCherryPickAndCheckResult(git, sideCommit,
 					MergeFailureReason.DIRTY_INDEX);
 		}
 	}
 
 	@Test
 	public void testCherryPickDirtyWorktree() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			// modify file a
 			writeTrashFile("a", "a(modified)");
 			// do not add and commit
 
 			doCherryPickAndCheckResult(git, sideCommit,
 					MergeFailureReason.DIRTY_WORKTREE);
 		}
 	}
 
 	@Test
 	public void testCherryPickConflictResolution() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 					.call();
 
 			assertEquals(CherryPickStatus.CONFLICTING, result.getStatus());
 			assertTrue(new File(db.getDirectory(), Constants.MERGE_MSG).exists());
 			assertEquals("side\n\nConflicts:\n\ta\n", db.readMergeCommitMsg());
 			assertTrue(new File(db.getDirectory(), Constants.CHERRY_PICK_HEAD)
 					.exists());
 			assertEquals(sideCommit.getId(), db.readCherryPickHead());
 			assertEquals(RepositoryState.CHERRY_PICKING, db.getRepositoryState());
 
 			// Resolve
 			writeTrashFile("a", "a");
 			git.add().addFilepattern("a").call();
 
 			assertEquals(RepositoryState.CHERRY_PICKING_RESOLVED,
 					db.getRepositoryState());
 
 			git.commit().setOnly("a").setMessage("resolve").call();
 
 			assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 		}
 	}
 
 	@Test
 	public void testCherryPickConflictResolutionNoCOmmit() throws Exception {
 		Git git = new Git(db);
 		RevCommit sideCommit = prepareCherryPick(git);
 
 		CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 				.setNoCommit(true).call();
 
 		assertEquals(CherryPickStatus.CONFLICTING, result.getStatus());
 		assertTrue(db.readDirCache().hasUnmergedPaths());
 		String expected = "<<<<<<< master\na(master)\n=======\na(side)\n>>>>>>> 527460a side\n";
 		assertEquals(expected, read("a"));
 		assertTrue(new File(db.getDirectory(), Constants.MERGE_MSG).exists());
 		assertEquals("side\n\nConflicts:\n\ta\n", db.readMergeCommitMsg());
 		assertFalse(new File(db.getDirectory(), Constants.CHERRY_PICK_HEAD)
 				.exists());
 		assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 
 		// Resolve
 		writeTrashFile("a", "a");
 		git.add().addFilepattern("a").call();
 
 		assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 
 		git.commit().setOnly("a").setMessage("resolve").call();
 
 		assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 	}
 
 	@Test
 	public void testCherryPickConflictReset() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 					.call();
 
 			assertEquals(CherryPickStatus.CONFLICTING, result.getStatus());
 			assertEquals(RepositoryState.CHERRY_PICKING, db.getRepositoryState());
 			assertTrue(new File(db.getDirectory(), Constants.CHERRY_PICK_HEAD)
 					.exists());
 
 			git.reset().setMode(ResetType.MIXED).setRef("HEAD").call();
 
 			assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 			assertFalse(new File(db.getDirectory(), Constants.CHERRY_PICK_HEAD)
 					.exists());
 		}
 	}
 
 	@Test
 	public void testCherryPickOverExecutableChangeOnNonExectuableFileSystem()
 			throws Exception {
 		try (Git git = new Git(db)) {
 			File file = writeTrashFile("test.txt", "a");
 			assertNotNull(git.add().addFilepattern("test.txt").call());
 			assertNotNull(git.commit().setMessage("commit1").call());
 
 			assertNotNull(git.checkout().setCreateBranch(true).setName("a").call());
 
 			writeTrashFile("test.txt", "b");
 			assertNotNull(git.add().addFilepattern("test.txt").call());
 			RevCommit commit2 = git.commit().setMessage("commit2").call();
 			assertNotNull(commit2);
 
 			assertNotNull(git.checkout().setName(Constants.MASTER).call());
 
 			DirCache cache = db.lockDirCache();
 			cache.getEntry("test.txt").setFileMode(FileMode.EXECUTABLE_FILE);
 			cache.write();
 			assertTrue(cache.commit());
 			cache.unlock();
 
 			assertNotNull(git.commit().setMessage("commit3").call());
 
 			db.getFS().setExecute(file, false);
 			git.getRepository()
 					.getConfig()
 					.setBoolean(ConfigConstants.CONFIG_CORE_SECTION, null,
 							ConfigConstants.CONFIG_KEY_FILEMODE, false);
 
 			CherryPickResult result = git.cherryPick().include(commit2).call();
 			assertNotNull(result);
 			assertEquals(CherryPickStatus.OK, result.getStatus());
 		}
 	}
 
 	@Test
 	public void testCherryPickConflictMarkers() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 					.call();
 			assertEquals(CherryPickStatus.CONFLICTING, result.getStatus());
 
 			String expected = "<<<<<<< master\na(master)\n=======\na(side)\n>>>>>>> 527460a side\n";
 			checkFile(new File(db.getWorkTree(), "a"), expected);
 		}
 	}
 
 	@Test
 	public void testCherryPickOurCommitName() throws Exception {
 		try (Git git = new Git(db)) {
 			RevCommit sideCommit = prepareCherryPick(git);
 
 			CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 					.setOurCommitName("custom name").call();
 			assertEquals(CherryPickStatus.CONFLICTING, result.getStatus());
 
 			String expected = "<<<<<<< custom name\na(master)\n=======\na(side)\n>>>>>>> 527460a side\n";
 			checkFile(new File(db.getWorkTree(), "a"), expected);
 		}
 	}
 
 	private RevCommit prepareCherryPick(final Git git) throws Exception {
 		// create, add and commit file a
 		writeTrashFile("a", "a");
 		git.add().addFilepattern("a").call();
 		RevCommit firstMasterCommit = git.commit().setMessage("first master")
 				.call();
 
 		// create and checkout side branch
 		createBranch(firstMasterCommit, "refs/heads/side");
 		checkoutBranch("refs/heads/side");
 		// modify, add and commit file a
 		writeTrashFile("a", "a(side)");
 		git.add().addFilepattern("a").call();
 		RevCommit sideCommit = git.commit().setMessage("side").call();
 
 		// checkout master branch
 		checkoutBranch("refs/heads/master");
 		// modify, add and commit file a
 		writeTrashFile("a", "a(master)");
 		git.add().addFilepattern("a").call();
 		git.commit().setMessage("second master").call();
 		return sideCommit;
 	}
 
 	private void doCherryPickAndCheckResult(final Git git,
 			final RevCommit sideCommit, final MergeFailureReason reason)
 			throws Exception {
 		// get current index state
 		String indexState = indexState(CONTENT);
 
 		// cherry-pick
 		CherryPickResult result = git.cherryPick().include(sideCommit.getId())
 				.call();
 		assertEquals(CherryPickStatus.FAILED, result.getStatus());
 		// staged file a causes DIRTY_INDEX
 		assertEquals(1, result.getFailingPaths().size());
 		assertEquals(reason, result.getFailingPaths().get("a"));
 		assertEquals("a(modified)", read(new File(db.getWorkTree(), "a")));
 		// index shall be unchanged
 		assertEquals(indexState, indexState(CONTENT));
 		assertEquals(RepositoryState.SAFE, db.getRepositoryState());
 
 		if (reason == null) {
 			ReflogReader reader = db.getReflogReader(Constants.HEAD);
 			assertTrue(reader.getLastEntry().getComment()
 					.startsWith("cherry-pick: "));
 			reader = db.getReflogReader(db.getBranch());
 			assertTrue(reader.getLastEntry().getComment()
 					.startsWith("cherry-pick: "));
 		}
 	}
 
 	/**
 	 * Cherry-picking merge commit M onto T
 	 * <pre>
 	 *    M
 	 *    |\
 	 *    C D
 	 *    |/
 	 * T  B
 	 * | /
 	 * A
 	 * </pre>
 	 * @throws Exception
 	 */
 	@Test
 	public void testCherryPickMerge() throws Exception {
 		try (Git git = new Git(db)) {
 			commitFile("file", "1\n2\n3\n", "master");
 			commitFile("file", "1\n2\n3\n", "side");
 			checkoutBranch("refs/heads/side");
 			RevCommit commitD = commitFile("file", "1\n2\n3\n4\n5\n", "side2");
 			commitFile("file", "a\n2\n3\n", "side");
 			MergeResult mergeResult = git.merge().include(commitD).call();
 			ObjectId commitM = mergeResult.getNewHead();
 			checkoutBranch("refs/heads/master");
 			RevCommit commitT = commitFile("another", "t", "master");
 
 			try {
 				git.cherryPick().include(commitM).call();
 				fail("merges should not be cherry-picked by default");
 			} catch (MultipleParentsNotAllowedException e) {
 				// expected
 			}
 			try {
 				git.cherryPick().include(commitM).setMainlineParentNumber(3).call();
 				fail("specifying a non-existent parent should fail");
 			} catch (JGitInternalException e) {
 				// expected
 				assertTrue(e.getMessage().endsWith(
 						"does not have a parent number 3."));
 			}
 
 			CherryPickResult result = git.cherryPick().include(commitM)
 					.setMainlineParentNumber(1).call();
 			assertEquals(CherryPickStatus.OK, result.getStatus());
 			checkFile(new File(db.getWorkTree(), "file"), "1\n2\n3\n4\n5\n");
 
 			git.reset().setMode(ResetType.HARD).setRef(commitT.getName()).call();
 
 			CherryPickResult result2 = git.cherryPick().include(commitM)
 					.setMainlineParentNumber(2).call();
 			assertEquals(CherryPickStatus.OK, result2.getStatus());
 			checkFile(new File(db.getWorkTree(), "file"), "a\n2\n3\n");
 		}
 	}
 }