def dirFile2 = dir1.createFile("dirFile2")
        def rootFile2 = root.createFile("rootFile2")

        def fileTree = new DirectoryFileTree(root, new PatternSet(), TestFiles.fileSystem(), false).postfix()

        when:
        fileTree.visit(visitor)

        then:
        visitor.visited.sort() == [rootFile1, rootFile2, dirFile2, dirFile1, dir1].sort()

        where:

        filteredPaths(unfiltered, include("**/*2")) == [root, dir1, dirFile2, subdir, rootFile2] as Set
        filteredPaths(unfiltered, include("dir1/**")) == [root, dir1, dirFile1, dirFile2, subdir, subdirFile1] as Set
        filteredPaths(unfiltered, include("*/subdir/**")) == [root, dir1, subdir, subdirFile1] as Set
        filteredPaths(unfiltered, include("dir1/dirFile1")) == [root, dir1, dirFile1] as Set
    }

    def "filters empty tree"() {

}

fun validateInstallDir(installDir: Directory) = installDir.also { dir ->
    val dirFile = dir.asFile
    if (dirFile.isFile) {
        throw RuntimeException("Install directory $dir is not valid: it is actually a file")
    }
    if (dirFile.list()?.isEmpty() != false) {
        return@also
    }
    val binDirFiles = dirFile.resolve("bin").list()

		t.Skip("skipping in short mode")
	}

	testenv.MustHaveGoBuild(t)

	// Collect non-test files.
	dirFiles := make(map[string][]string)
	root := filepath.Join(testenv.GOROOT(t), "src")
	walkPkgDirs(root, func(dir string, filenames []string) {
		dirFiles[dir] = filenames
	}, t.Error)

	c := &stdlibChecker{
		dirFiles: dirFiles,
		pkgs:     make(map[string]*futurePackage),
	}

	start := time.Now()

		t.Skip("skipping in short mode")
	}

	testenv.MustHaveGoBuild(t)

	// Collect non-test files.
	dirFiles := make(map[string][]string)
	root := filepath.Join(testenv.GOROOT(t), "src")
	walkPkgDirs(root, func(dir string, filenames []string) {
		dirFiles[dir] = filenames
	}, t.Error)

	c := &stdlibChecker{
		dirFiles: dirFiles,
		pkgs:     make(map[string]*futurePackage),
	}

	start := time.Now()

// used in the hash function.
func HashDir(dir, prefix string, hash Hash) (string, error) {
	files, err := DirFiles(dir, prefix)
	if err != nil {
		return "", err
	}
	osOpen := func(name string) (io.ReadCloser, error) {
		return os.Open(filepath.Join(dir, strings.TrimPrefix(name, prefix)))
	}
	return hash(files, osOpen)
}

// DirFiles returns the list of files in the tree rooted at dir,

	}
	wantDir := filepath.Join(dir, ".git")
	return wantDir == gitDir
}

type dirFile struct {
	filePath, slashPath string
	info                os.FileInfo
}

func (f dirFile) Path() string                 { return f.slashPath }
func (f dirFile) Lstat() (os.FileInfo, error)  { return f.info, nil }
func (f dirFile) Open() (io.ReadCloser, error) { return os.Open(f.filePath) }

type zipFile struct {
	name string