import java.io.File;
import static java.nio.StandardCharsets.UTF_8;
import static deepdive.ExpectThat.expectThat;		
	
// inside a test method:		
File dir = ...                     // dir is a File object which we expect to be a directory  
expectThat(dir)                    // starting with a deepdive.actual.io.FileActual to test the directory
    .isDirectory()                 // test a File property
    .name()                        // dive into a deepdive.actual.lang.StringActual to test the File name
    	.startsWith("test_")       // test a File name property
    	.endsWith("_files")        // test a File name property
    	.back()                    // back to the FileActual
    .set().childFile("result.txt") // replace the actual File value with a child File
    .exists()                      // test a File property
    .isFile()                      // test a File property
    .not().isHidden()              // negate any available assertion by a preceding not() 
    .length()                      // dive into a deepdive.actual.lang.LongActual to the test the file length
        .greater(50)               // test a File length property
        .back()                    // back to the FileActual
    .read(UTF_8).lineIterator()    // read file content as lines and dive into a deepdive.actual.util.StringIteratorActual 
        .next()                    // dive into a StringActual for the first line 
            .startsWith("Hold your breath") // tests a line property
            .back()                // back to the StringIteratorActual
        .skip(5)                   // skip 5 lines
        .next()                    // dive into a StringActual to test the next line
            .isLowerCase()         // test a line property
            .back()                // back to the StringIteratorActual
    	.not().hasNext();          // test for iteration end: done!