return transformValues(Maps.<String, String>newHashMap(), Functions.<String>identity());
  }

  @Override
  protected Map<String, String> makePopulatedMap() {
    Map<String, Integer> underlying = Maps.newHashMap();
    underlying.put("a", 1);
    underlying.put("b", 2);
    underlying.put("c", 3);
    return transformValues(underlying, Functions.toStringFunction());
  }

    return transformValues(Maps.<String, String>newTreeMap(), Functions.<String>identity());
  }

  @Override
  protected SortedMap<String, String> makePopulatedMap() {
    SortedMap<String, Integer> underlying = Maps.newTreeMap();
    underlying.put("a", 1);
    underlying.put("b", 2);
    underlying.put("c", 3);
    return transformValues(underlying, Functions.toStringFunction());
  }

Lkotlin/jvm/functions/Function1;
Lkotlin/jvm/functions/Function20;
Lkotlin/jvm/functions/Function21;
Lkotlin/jvm/functions/Function22;
Lkotlin/jvm/functions/Function2;
Lkotlin/jvm/functions/Function3;
Lkotlin/jvm/functions/Function4;
Lkotlin/jvm/functions/Function5;
Lkotlin/jvm/functions/Function6;
Lkotlin/jvm/functions/Function7;
Lkotlin/jvm/functions/Function8;
Lkotlin/jvm/functions/Function9;
Lkotlin/jvm/internal/ArrayIterator;

### Other utility functions

Any other utility function that you call directly can be created with normal `def` or `async def` and FastAPI won't affect the way you call it.

This is in contrast to the functions that FastAPI calls for you: *path operation functions* and dependencies.

    EquivalenceTester.of(Equivalence.equals().onResultOf(Functions.toStringFunction()))
        .addEquivalenceGroup(new IntValue(1), new IntValue(1))
        .addEquivalenceGroup(new IntValue(2))
        .test();
  }

  public void testOnResultOf_equals() {
    new EqualsTester()
        .addEqualityGroup(
            Equivalence.identity().onResultOf(Functions.toStringFunction()),

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.hash;


/**
 * An enum that contains all of the known hash functions.
 *
 * @author Kurt Alfred Kluever
 */
enum HashFunctionEnum {
  ADLER32(Hashing.adler32()),
  CRC32(Hashing.crc32()),
  GOOD_FAST_HASH_32(Hashing.goodFastHash(32)),
  GOOD_FAST_HASH_64(Hashing.goodFastHash(64)),

  // Following are helper functions to assist integrating TFRT with current
  // TF eager runtime.
  // TODO(b/172877902): These helper functions are currently used to support
  // PyFuncOp on TFRT, and might be useful for ops that directly use low
  // level TF APIs. Remove/replace the following functions when TFRT native
  // ops are implemented.

///

/// tip

If you want to call `async` functions in your tests apart from sending requests to your FastAPI application (e.g. asynchronous database functions), have a look at the [Async Tests](../advanced/async-tests.md){.internal-link target=_blank} in the advanced tutorial.

///

## Separating tests

## Parameterized dependencies

All the dependencies we have seen are a fixed function or class.

But there could be cases where you want to be able to set parameters on the dependency, without having to declare many different functions or classes.

Let's imagine that we want to have a dependency that checks if the query parameter `q` contains some fixed content.

But we want to be able to parameterize that fixed content.

## A "callable" instance

    checkArgument(!list.isEmpty(), "number of hash functions (%s) must be > 0", list.size());
    return new ConcatenatedHashFunction(list.toArray(new HashFunction[0]));
  }

  private static final class ConcatenatedHashFunction extends AbstractCompositeHashFunction {

    private ConcatenatedHashFunction(HashFunction... functions) {
      super(functions);
      for (HashFunction function : functions) {
        checkArgument(