{
  "kind": "NetworkPolicy",
  "apiVersion": "extensions/v1beta1",
  "metadata": {
    "name": "nameValue",
    "generateName": "generateNameValue",
    "namespace": "namespaceValue",
    "selfLink": "selfLinkValue",
    "uid": "uidValue",
    "resourceVersion": "resourceVersionValue",
    "generation": 7,
    "creationTimestamp": "2008-01-01T01:01:01Z",
    "deletionTimestamp": "2009-01-01T01:01:01Z",
    "deletionGracePeriodSeconds": 10,

    }

    @Test
    fun `can get generic extension by type`() {

        val extensionAware = mock<ExtensionAware>()
        val extensions = mock<ExtensionContainer>()
        val extension = mock<NamedDomainObjectContainer<List<String>>>()
        val extensionType = typeOf<NamedDomainObjectContainer<List<String>>>()

        whenever(extensionAware.extensions)
            .thenReturn(extensions)

    private final Map<String, ExtensionHolder<?>> extensions = new LinkedHashMap<>();

    public <T> void add(TypeOf<T> publicType, String name, T extension) {
        if (hasExtension(name)) {
            throw new IllegalArgumentException(
                format("Cannot add extension with name '%s', as there is an extension already registered with that name.", name));
        }

    }

    def "can create ExtensionAware extensions"() {
        given:
        container.add("foo", Parent)
        def extension = container.getByName("foo")

        expect:
        extension instanceof ExtensionAware

        when:
        extension.extensions.create("thing", Thing, "bar")

        then:
        extension.thing.name == "bar"
    }

		}
		return
	}
	for i, s := range b.extensions {
		if s[0] == e[0] {
			if e[0] == 'u' {
				b.extensions[i] += e[1:]
			}
			return
		}
	}
	b.extensions = append(b.extensions, e)
}

// SetExt sets the extension e to the tag. e must be a valid extension as
// returned by Tag.Extension. If the extension already exists, it will be
// overwritten, except for a -u extension, where the individual key-type pairs

	mimeTypesLower sync.Map // map[string]string; ".z" => "application/x-compress"

	// extensions maps from MIME type to list of lowercase file
	// extensions: "image/jpeg" => [".jpg", ".jpeg"]
	extensionsMu sync.Mutex // Guards stores (but not loads) on extensions.
	extensions   sync.Map   // map[string][]string; slice values are append-only.
)

// tag::convention[]
// tag::create-extension[]
// tag::extension[]
// Create extension object
interface GreetingPluginExtension {
    Property<String> getMessage()
}
// end::extension[]

// Add the 'greeting' extension object to project
def extension = project.extensions.create("greeting", GreetingPluginExtension)
// end::create-extension[]

// Set a default value for 'message'
extension.message.convention("Hello from Gradle")

 *
 * <pre class='autoTested'>
 * // Extensions are just plain objects, there is no interface/type
 * class MyExtension {
 *   String foo
 *
 *   MyExtension(String foo) {
 *     this.foo = foo
 *   }
 * }
 *
 * // Add new extensions via the extension container
 * project.extensions.create('custom', MyExtension, "bar")

 * Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits=15
 * Sec-WebSocket-Extensions: permessage-deflate; client_no_context_takeover
 * Sec-WebSocket-Extensions: permessage-deflate; server_max_window_bits="15"
 * Sec-WebSocket-Extensions: permessage-deflate; server_max_window_bits=15
 * Sec-WebSocket-Extensions: permessage-deflate; server_no_context_takeover
 * Sec-WebSocket-Extensions: permessage-deflate; server_no_context_takeover;

            println("extension: " + typeOf(extension))
            extension { println("extension{} " + typeOf(this)) }
            """
        )

        assertThat(
            build("help", "-q").output,
            containsMultiLineString(
                """
                extension: Extension
                extension{} Extension
                """
            )
        )