NLST returning non-empty listing for non-existent files

[anowicki-egnyte]

The NLST FTP command, when issued with the name of a non-existent file as an argument, returns that name instead of an empty list. Compare this behavior to that of the LIST command, which correctly returns an empty list in such a case.

A test case reproducing the bug (using the FTP client from the commons-net package):

    @Test
    void shouldReturnEmptyListingOfNonExistingFiles() {
        ftpClient.connect(IP, PORT);
        ftpClient.login(USERNAME, PASSWORD);
        ftpClient.enterLocalPassiveMode();

        // this assertion passes
        assertThat(ftpClient.listFiles(UUID.randomUUID().toString()), is(emptyArray()));
        // while this one fails
        assertThat(ftpClient.listNames(UUID.randomUUID().toString()), is(emptyArray()));
    }