def "stats a symlink cycle"() {
        def first = tmpDir.file("first")
        def second = tmpDir.file("second")
        def third = tmpDir.file("third")
        first.createLink(second)
        second.createLink(third)
        third.createLink(first)

        expect:
        def stat = accessor.stat(first)
        stat.type == FileType.Missing
        stat.lastModified == 0
        stat.length == 0

        def linkTarget3 = tmpDir.createFile("linkTarget3")

        rootDir.createLink(linkTarget1)
        linkTarget1.file("includedSymlink").createLink(linkTarget2)
        linkTarget1.file("excludedSymlink").createLink(linkTarget2)
        linkTarget2.file("symlinkedFile.txt").createLink(linkTarget3)
        linkTarget2.file("excludedSymlinkedFile.png").createLink(linkTarget3)

        // rootDir -> linkTarget1
        //   - included

    def "supplies installations with symlinked candidate"() {
        given:
        def real = candidates.createDir("java/11.0.6.hs-adpt")
        def symlink = candidates.file("java/symlink").createLink(real)

        when:
        def directories = supplier.get()

        then:
        directories.size() == 2
        directories*.location.containsAll(real, symlink)

        ex.message.contains "Cannot convert a null value to a File or URI."
    }

    def createLink(File link, File target) {
        createLink(link, target.absolutePath)
    }

    def createLink(File link, String target) {
        new TestFile(link).createLink(target)
    }

    def createFile(File file) {
        file.parentFile.mkdirs()
        file.text = 'content'

        def baseDir = file('build')
        baseDir.file('file').text = 'some contents'
        def symlinked = baseDir.file('symlinked')
        symlinked.text = 'target of symlink'
        baseDir.file('symlink').createLink(symlinked)

        buildScript << """
            def baseDir = new File("${escapeString(baseDir)}")
            def file = new File(baseDir, "file")
            def symlink = new File(baseDir, "symlink")

}
"""
    }

    def "uses the target of symlink for input file content"() {
        file("in-dir").createDir()
        def inFile = file("other").createFile()
        def link = file("in.txt")
        link.createLink("other")

        given:
        run("work")
        run("work")
        result.assertTasksSkipped(":work")

        when:
        inFile.text = 'new content'
        run("work")

        then:

    def "gracefully handle when declaring the same path as an input via symlinks"() {
        def actualDir = file("actualDir").createDir()
        file("symlink1").createLink(actualDir)
        file("symlink2").createLink(actualDir)

        buildFile << """
            task myTask {
                def outputFile = file("build/output.txt")
                inputs.dir("symlink1")

    def "supplies installations with symlinked candidate"() {
        given:
        def real = candidates.createDir("installs/java/11.0.6.hs-adpt")
        def symlink = candidates.file("installs/java/symlink").createLink(real)

        when:
        def directories = supplier.get()

        then:
        directories.size() == 2
        directories*.location.containsAll(real, symlink)

    def fileSystemAccess = TestFiles.fileSystemAccess()

    def "root broken symlink is ignored for #strategyName"() {
        given:
        def root = file('root')
        root.createLink(file('non-existing'))

        when:
        def fingerprints = strategy.collectFingerprints(snapshot(root))

        then:
        fingerprints.isEmpty()

        where:

@Requires(UnitTestPreconditions.UnixDerivative)
class DeleteTaskUnixDerivativeSymlinkIntegrationTest extends DeleteIntegrationTest {
    @Override
    protected void createSymbolicLink(TestFile link, TestFile target) {
        link.createLink(target)
    }