sb.WriteByte(',')
					id = id[3:]
				} else if len(id) > 4 && id[1] == 'u' && id[4] == '$' {
					dig1, ok1 := hexDigit(id[2])
					dig2, ok2 := hexDigit(id[3])
					val := (dig1 << 4) | dig2
					if !ok1 || !ok2 || dig1 > 7 || val < ' ' {
						valid = false
					} else {
						sb.WriteByte(val)
						id = id[5:]
					}

        flatten(set) == [parent.path, "1:dir1", "1:common", "2:dir2", "2:dir3"]
    }

    def "creates from files where one file is ancestor of the others"() {
        def dir1 = tmpDir.createDir("dir1")
        def dir2 = dir1.createDir("dir2")

        expect:
        def set = from(dir2, dir1)
        set.contains(dir1)
        set.contains(dir2)
        set.contains(dir1.file("child"))

        flatten(set) == [parent.path, "1:common", "2:dir2", "3:child", "2:dir3", "3:child", "1:dir1", "2:child"]
    }

    def "creates from files where one file is ancestor of the others"() {
        def dir1 = tmpDir.createDir("dir1")
        def dir2 = dir1.createDir("dir2")
        def dir1Child = dir1.file("child")
        dir1Child.createFile()

    def "can determine a VS2017 version of an install from command line"() {
        def dir1 = tmpDir.createDir("dir1")
        def dir2 = tmpDir.createDir("dir2")
        def dir3 = tmpDir.createDir("dir3")

        given:
        vswhereInstall(dir1, "15.3.26730.16")
        vswhereInstall(dir2, "14.0")
        vswhereInstall(dir3, "12.0")

        when:

    }

    void addsResolvedSourceDirectory() {
        when:
        set.srcDir 'dir1'

        then:
        set.srcDirs equalTo([new File(testDir, 'dir1')] as Set)
    }

    void addsResolvedSourceDirectories() {
        when:
        set.srcDir {-> ['dir1', 'dir2'] }

        then:
        set.srcDirs equalTo([new File(testDir, 'dir1'), new File(testDir, 'dir2')] as Set)
    }

        1 * visitor.visitDir({ it.file == tempDir.file("dir2/dir1") })
        1 * visitor.visitDir({ it.file == tempDir.file("dir2/dir2") })
        1 * visitor.visitFile({ it.file == tempDir.file("dir2/dir1/file1") })
        1 * visitor.visitFile({ it.file == tempDir.file("dir2/dir1/file2") })
        1 * visitor.visitFile({ it.file == tempDir.file("dir2/dir1/file3") })
        0 * _

        where:

        result.component.baseDir == dir1
        def platformSdk = result.component.forPlatform(x64())
        platformSdk.includeDirs == [ dir1.file("Include/${expected}/um"), dir1.file("Include/${expected}/shared") ]
        platformSdk.path == [dir1.file("bin/x64")]
        platformSdk.libDirs == [dir1.file("Lib/${expected}/um/x64")]

        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"() {

        root.createFile("rootFile1")
        def dir1 = root.createDir("dir1")
        dir1.createFile("dirFile1")
        def dirFile2 = dir1.createFile("dirFile2")
        root.createFile("rootFile2")

        and:
        def patterns = new PatternSet()
        patterns.include("**/*2")
        def filter = new PatternSet()
        filter.include("dir1/**")

        and:

                preserve {
                  include 'extraDir/**'
                  include 'dir1/**'
                  exclude 'dir1/extra.txt'
                }
            }
        '''.stripIndent()

        when:
        run 'sync'

        then:
        file('dest').assertHasDescendants(
            'dir1/file1.txt',
            'dir2/subdir/file2.txt',
            'dir2/file3.txt',