@Test
    public void testGetAliasForJavaScript() throws Exception {
        MimeType mt = this.mimeTypes.forName("text/javascript");
        Set<String> aliases = mimeTypes.getMediaTypeRegistry()
                .getAliases(mt.getType())
                .stream()
                .map(MediaType::toString)
                .collect(Collectors.toSet());
        assertEquals(Set.of("application/javascript", "application/x-javascript"), aliases);
    }
TIKA-2460 Test loading of custom-mimetypes.xml from sys prop.
tika-core/src/test/java/org/apache/tika/mime/MimeTypesReaderTest.java