@Test
void loadPrefixedConfigItems_multiplePrefixes_callFirstPrefix() throws IOException, ConfigKeysNotRecognisedException {

    Builder builder = new Builder(new String[]{});
    ConfigManager configManager = builder.loadConfigFromResourceOrFile(ImmutableList.of("src/test/prefixes-test-config-file.properties"), ImmutableSet.of(TestConfig.class, TestConfigDummy.class))
            .build();
    Config<TestConfig> testConfig = configManager.getConfig(TestConfig.class);
    // Default (initial) config values.
    assertThat(testConfig.getValue(TestConfig.FOO).asInt()).isEqualTo(1);
    assertThat(testConfig.getValue(TestConfig.BAR).asInt()).isEqualTo(2);
    assertThat(testConfig.getPrefixedConfigItems("Prefix2").getValues().values().stream()
            .allMatch(configValue -> configValue.currentValue == null)).isFalse();
    assertThat(testConfig.getPrefixedConfigItems("Prefix2").getValues().values().stream()
            .allMatch(configValue -> configValue.prefixedValues == null)).isFalse();
}