/*
    * Copyright (C) 2012, IBM Corporation
    * 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.
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   * 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
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   *   with the distribution.
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   * - Neither the name of the Eclipse Foundation, Inc. nor the
   *   names of its contributors may be used to endorse or promote
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   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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  package org.eclipse.jgit.pgm;
  
  import static org.junit.Assert.assertArrayEquals;
  import static org.junit.Assert.assertNotNull;
  
  import java.io.File;
  import java.util.List;
  
  import org.eclipse.jgit.api.Git;
  import org.eclipse.jgit.api.errors.CheckoutConflictException;
  import org.eclipse.jgit.diff.DiffEntry;
  import org.eclipse.jgit.lib.CLIRepositoryTestCase;
  import org.eclipse.jgit.lib.FileMode;
  import org.eclipse.jgit.lib.Ref;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.treewalk.FileTreeIterator;
  import org.eclipse.jgit.treewalk.FileTreeIterator.FileEntry;
  import org.eclipse.jgit.treewalk.TreeWalk;
  import org.eclipse.jgit.util.FileUtils;
  import org.junit.Assert;
  import org.junit.Test;
  
  public class CheckoutTest extends CLIRepositoryTestCase {
  
  	@Test
  	public void testCheckoutSelf() throws Exception {
  		new Git(db).commit().setMessage("initial commit").call();
  
  		assertEquals("Already on 'master'", execute("git checkout master"));
  	}
  
  	@Test
  	public void testCheckoutBranch() throws Exception {
  		new Git(db).commit().setMessage("initial commit").call();
  		new Git(db).branchCreate().setName("side").call();
  
  		assertEquals("Switched to branch 'side'", execute("git checkout side"));
  	}
  
  	@Test
  	public void testCheckoutNewBranch() throws Exception {
  		new Git(db).commit().setMessage("initial commit").call();
  
  		assertEquals("Switched to a new branch 'side'",
  				execute("git checkout -b side"));
  	}
  
  	@Test
  	public void testCheckoutNonExistingBranch() throws Exception {
  		assertEquals(
  				"error: pathspec 'side' did not match any file(s) known to git.",
  				execute("git checkout side"));
  	}
  
  	@Test
  	public void testCheckoutNewBranchThatAlreadyExists() throws Exception {
  		new Git(db).commit().setMessage("initial commit").call();
 
 		assertEquals("fatal: A branch named 'master' already exists.",
 				execute("git checkout -b master"));
 	}
 
 	@Test
 	public void testCheckoutNewBranchOnBranchToBeBorn() throws Exception {
 		assertEquals("fatal: You are on a branch yet to be born",
 				execute("git checkout -b side"));
 	}
 
 	@Test
 	public void testCheckoutUnresolvedHead() throws Exception {
 		assertEquals(
 				"error: pathspec 'HEAD' did not match any file(s) known to git.",
 				execute("git checkout HEAD"));
 	}
 
 	@Test
 	public void testCheckoutHead() throws Exception {
 		new Git(db).commit().setMessage("initial commit").call();
 
 		assertEquals("", execute("git checkout HEAD"));
 	}
 
 	@Test
 	public void testCheckoutExistingBranchWithConflict() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("a", "Hello world a");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("commit file a").call();
 		git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/b", "Hello world b");
 		git.add().addFilepattern("a/b").call();
 		git.commit().setMessage("commit folder a").call();
 		git.rm().addFilepattern("a").call();
 		writeTrashFile("a", "New Hello world a");
 		git.add().addFilepattern(".").call();
 
 		String[] execute = execute("git checkout branch_1");
 		Assert.assertEquals(
 				"error: Your local changes to the following files would be overwritten by checkout:",
 				execute[0]);
 		Assert.assertEquals("\ta", execute[1]);
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'a' and 'b'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>modify file 'a'
 	 * <li>Commit
 	 * <li>Delete file 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The working tree should contain 'a' with FileMode.REGULAR_FILE after the
 	 * checkout.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void testCheckoutWithMissingWorkingTreeFile() throws Exception {
 		Git git = new Git(db);
 		File fileA = writeTrashFile("a", "Hello world a");
 		writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add files a & b").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		writeTrashFile("a", "b");
 		git.add().addFilepattern("a").call();
 		git.commit().setMessage("modify file a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		FileUtils.delete(fileA);
 
 		git.checkout().setName(branch_1.getName()).call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 		assertEquals("Hello world a", read(fileA));
 	}
 
 	@Test
 	public void testCheckoutOrphan() throws Exception {
 		Git git = new Git(db);
 		git.commit().setMessage("initial commit").call();
 
 		assertEquals("Switched to a new branch 'new_branch'",
 				execute("git checkout --orphan new_branch"));
 		assertEquals("refs/heads/new_branch", db.getRef("HEAD").getTarget().getName());
 		RevCommit commit = git.commit().setMessage("orphan commit").call();
 		assertEquals(0, commit.getParentCount());
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'b'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Add folder 'a'
 	 * <li>Commit
 	 * <li>Replace folder 'a' by file 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The working tree should contain 'a' with FileMode.REGULAR_FILE after the
 	 * checkout.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestMissingThenFolderWithFileInWorkingTree()
 			throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add file b").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		File folderA = new File(db.getWorkTree(), "a");
 		FileUtils.mkdirs(folderA);
 		writeTrashFile("a/c", "Hello world c");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add folder a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 
 		FileUtils.delete(folderA, FileUtils.RECURSIVE);
 		writeTrashFile("a", "b");
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		git.checkout().setName(branch_1.getName()).call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Replace file 'a' by folder 'a'
 	 * <li>Commit
 	 * <li>Delete folder 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The working tree should contain 'a' with FileMode.REGULAR_FILE after the
 	 * checkout.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestFolderWithMissingInWorkingTree() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("b", "Hello world b");
 		writeTrashFile("a", "b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add file b & file a").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		File folderA = new File(db.getWorkTree(), "a");
 		FileUtils.mkdirs(folderA);
 		writeTrashFile("a/c", "Hello world c");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add folder a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 
 		FileUtils.delete(folderA, FileUtils.RECURSIVE);
 
 		git.checkout().setName(branch_1.getName()).call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Delete file 'a'
 	 * <li>Commit
 	 * <li>Add folder 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The checkout command should raise an error. The conflicting paths are 'a'
 	 * and 'a/c'.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestMissingWithFolderInWorkingTree() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("b", "Hello world b");
 		writeTrashFile("a", "b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add file b & file a").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		git.commit().setMessage("delete file a").call();
 
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/c", "Hello world c");
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 
 		CheckoutConflictException exception = null;
 		try {
 			git.checkout().setName(branch_1.getName()).call();
 		} catch (CheckoutConflictException e) {
 			exception = e;
 		}
 		assertNotNull(exception);
 		assertEquals(2, exception.getConflictingPaths().size());
 		assertEquals("a", exception.getConflictingPaths().get(0));
 		assertEquals("a/c", exception.getConflictingPaths().get(1));
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add folder 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Delete folder 'a'
 	 * <li>Commit
 	 * <li>Add file 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The checkout command should raise an error. The conflicting path is 'a'.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestFolderThenMissingWithFileInWorkingTree()
 			throws Exception {
 		Git git = new Git(db);
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/c", "Hello world c");
 		writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern(".").call();
 		RevCommit commit1 = git.commit().setMessage("add folder a & file b")
 				.call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		RevCommit commit2 = git.commit().setMessage("delete folder a").call();
 
 		TreeWalk tw = new TreeWalk(db);
 		tw.addTree(commit1.getTree());
 		tw.addTree(commit2.getTree());
 		List<DiffEntry> scan = DiffEntry.scan(tw);
 		assertEquals(1, scan.size());
 		assertEquals(FileMode.MISSING, scan.get(0).getNewMode());
 		assertEquals(FileMode.TREE, scan.get(0).getOldMode());
 
 		writeTrashFile("a", "b");
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		CheckoutConflictException exception = null;
 		try {
 			git.checkout().setName(branch_1.getName()).call();
 		} catch (CheckoutConflictException e) {
 			exception = e;
 		}
 		assertNotNull(exception);
 		assertEquals(1, exception.getConflictingPaths().size());
 		assertEquals("a", exception.getConflictingPaths().get(0));
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add folder 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Replace folder 'a'by file 'a'
 	 * <li>Commit
 	 * <li>Delete file 'a' in the working tree
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The working tree should contain 'a' with FileMode.TREE after the
 	 * checkout.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestFolderThenFileWithMissingInWorkingTree()
 			throws Exception {
 		Git git = new Git(db);
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/c", "Hello world c");
 		writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add folder a & file b").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		File fileA = new File(db.getWorkTree(), "a");
 		writeTrashFile("a", "b");
 		git.add().addFilepattern("a").call();
 		git.commit().setMessage("add file a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		FileUtils.delete(fileA);
 
 		git.checkout().setName(branch_1.getName()).call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Modify file 'a'
 	 * <li>Commit
 	 * <li>Delete file 'a' & replace by folder 'a' in the working tree & index
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The checkout command should raise an error. The conflicting path is 'a'.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestFileThenFileWithFolderInIndex() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("a", "Hello world a");
 		writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add files a & b").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		writeTrashFile("a", "b");
 		git.add().addFilepattern("a").call();
 		git.commit().setMessage("add file a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		git.rm().addFilepattern("a").call();
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/c", "Hello world c");
 		git.add().addFilepattern(".").call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 
 		CheckoutConflictException exception = null;
 		try {
 			git.checkout().setName(branch_1.getName()).call();
 		} catch (CheckoutConflictException e) {
 			exception = e;
 		}
 		assertNotNull(exception);
 		assertEquals(1, exception.getConflictingPaths().size());
 		assertEquals("a", exception.getConflictingPaths().get(0));
 	}
 
 	/**
 	 * Steps:
 	 * <ol>
 	 * <li>Add file 'a'
 	 * <li>Commit
 	 * <li>Create branch '1'
 	 * <li>Modify file 'a'
 	 * <li>Commit
 	 * <li>Delete file 'a' & replace by folder 'a' in the working tree & index
 	 * <li>Checkout branch '1'
 	 * </ol>
 	 * <p>
 	 * The checkout command should raise an error. The conflicting paths are 'a'
 	 * and 'a/c'.
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void fileModeTestFileWithFolderInIndex() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("b", "Hello world b");
 		writeTrashFile("a", "b");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("add file b & file a").call();
 		Ref branch_1 = git.branchCreate().setName("branch_1").call();
 		git.rm().addFilepattern("a").call();
 		writeTrashFile("a", "Hello world a");
 		git.add().addFilepattern("a").call();
 		git.commit().setMessage("add file a").call();
 
 		FileEntry entry = new FileTreeIterator.FileEntry(new File(
 				db.getWorkTree(), "a"), db.getFS());
 		assertEquals(FileMode.REGULAR_FILE, entry.getMode());
 
 		git.rm().addFilepattern("a").call();
 		FileUtils.mkdirs(new File(db.getWorkTree(), "a"));
 		writeTrashFile("a/c", "Hello world c");
 		git.add().addFilepattern(".").call();
 
 		entry = new FileTreeIterator.FileEntry(new File(db.getWorkTree(), "a"),
 				db.getFS());
 		assertEquals(FileMode.TREE, entry.getMode());
 
 		CheckoutConflictException exception = null;
 		try {
 			git.checkout().setName(branch_1.getName()).call();
 		} catch (CheckoutConflictException e) {
 			exception = e;
 		}
 		assertNotNull(exception);
 		assertEquals(1, exception.getConflictingPaths().size());
 		assertEquals("a", exception.getConflictingPaths().get(0));
 
 		// TODO: ideally we'd like to get two paths from this exception
 		// assertEquals(2, exception.getConflictingPaths().size());
 		// assertEquals("a", exception.getConflictingPaths().get(0));
 		// assertEquals("a/c", exception.getConflictingPaths().get(1));
 	}
 
 	static private void assertEquals(Object expected, Object actual) {
 		Assert.assertEquals(expected, actual);
 	}
 
 	static private void assertEquals(String expected, String[] actual) {
 		// if there is more than one line, ignore last one if empty
 		Assert.assertEquals(
 				1,
 				actual.length > 1 && actual[actual.length - 1].equals("") ? actual.length - 1
 						: actual.length);
 		Assert.assertEquals(expected, actual[0]);
 	}
 
 	@Test
 	public void testCheckoutPath() throws Exception {
 		Git git = new Git(db);
 		writeTrashFile("a", "Hello world a");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("commit file a").call();
 		git.branchCreate().setName("branch_1").call();
 		git.checkout().setName("branch_1").call();
 		File b = writeTrashFile("b", "Hello world b");
 		git.add().addFilepattern("b").call();
 		git.commit().setMessage("commit file b").call();
 		File a = writeTrashFile("a", "New Hello world a");
 		git.add().addFilepattern(".").call();
 		git.commit().setMessage("modified a").call();
 		assertArrayEquals(new String[] { "" },
 				execute("git checkout HEAD~2 -- a"));
 		assertEquals("Hello world a", read(a));
 		assertArrayEquals(new String[] { "* branch_1", "  master", "" },
 				execute("git branch"));
 		assertEquals("Hello world b", read(b));
 	}
 }