@Test
public final void testReadFileShouldReturnFileInputStreamIfFileExists() throws FileNotFoundException {

    // GIVEN
    given(path.resolve(FILE_NAME)).willReturn(messageFilePath);
    given(messageFilePath.toFile()).willReturn(messageFile);
    given(messageFile.exists()).willReturn(true);
    given(messageFile.isFile()).willReturn(true);
    given(fileInputStreamFactory.createFileInputStream(messageFile)).willReturn(fileInputStream);
    // WHEN
    InputStream actual = underTest.readFile(FILE_NAME, path);
    // THEN
    assertEquals(actual, fileInputStream);
}