Some requests will have a cached response. When this cached response isn’t fresh, OkHttp can do a _conditional GET_ to download an updated response if it’s newer than what’s cached. This requires headers like `If-Modified-Since` and `If-None-Match` to be added.

## Rewriting Responses

      return this;
    }

    public <E> Interner<E> build() {
      if (!strong) {
        mapMaker.weakKeys();
      }
      return new InternerImpl<>(mapMaker);
    }
  }

  /** Returns a fresh {@link InternerBuilder} instance. */
  public static InternerBuilder newBuilder() {
    return new InternerBuilder();
  }

  /**

import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Pattern;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Generates fresh instances of types that are different from each other (if possible).
 *
 * @author Ben Yu
 */
@GwtIncompatible
@J2ktIncompatible
@NullUnmarked
@SuppressWarnings("nullness")
class FreshValueGenerator {

    List<Object> equalArgs = new ArrayList<>(args);
    for (int i = 0; i < args.size(); i++) {
      Parameter param = params.get(i);
      Object arg = args.get(i);
      // Use new fresh value generator because 'args' were populated with new fresh generator each.
      // Two newFreshValueGenerator() instances should normally generate equal value sequence.
      Object shouldBeEqualArg = generateDummyArg(param, newFreshValueGenerator());

And if you update that local FastAPI source code when you run that Python file again, it will use the fresh version of FastAPI you just edited.

That way, you don't have to "install" your local version to be able to test every change.

/// note | Technical Details

      assertWithMessage("Expected to return non-null for: %s", mutableClass)
          .that(instance)
          .isNotNull();
      assertWithMessage("Expected to return fresh instance for: " + mutableClass)
          .that(ArbitraryInstances.get(mutableClass))
          .isNotSameInstanceAs(instance);
    }
  }

  private enum EmptyEnum {}

  private enum Direction {

      segmentSize <<= 1;
    }

    for (int i = 0; i < this.segments.length; ++i) {
      this.segments[i] = createSegment(segmentSize);
    }
  }

  /** Returns a fresh {@link MapMakerInternalMap} as specified by the given {@code builder}. */
  static <K, V> MapMakerInternalMap<K, V, ? extends InternalEntry<K, V, ?>, ?> create(
      MapMaker builder) {

      segmentSize <<= 1;
    }

    for (int i = 0; i < this.segments.length; ++i) {
      this.segments[i] = createSegment(segmentSize);
    }
  }

  /** Returns a fresh {@link MapMakerInternalMap} as specified by the given {@code builder}. */
  static <K, V> MapMakerInternalMap<K, V, ? extends InternalEntry<K, V, ?>, ?> create(
      MapMaker builder) {

     * @param host an IP address or hostname.
     * @param port the IP port associated with the service.
     * @param maxAge time in seconds that this alternative is considered fresh.
     */
    fun alternateService(
      streamId: Int,
      origin: String,
      protocol: ByteString,
      host: String,
      port: Int,
      maxAge: Long,
    )
  }

    )
    assertThat(get(server.url("/")).body.string()).isEqualTo("A")
    val request =
      Request
        .Builder()
        .url(server.url("/"))
        .header("Cache-Control", "min-fresh=120")
        .build()
    val response = client.newCall(request).execute()
    assertThat(response.body.string()).isEqualTo("B")
  }

  @Test
  fun requestMaxStale() {
    server.enqueue(