return t;
  }

  /** Returns {@code null} as any type, even one that does not include {@code null}. */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

 * way to check an object at runtime to be an instance of a {@link TypeToken}. Instead, caller
 * should use the type safe {@link #putInstance}.
 *
 * <p>Also, if caller suppresses unchecked warnings and passes in an {@code Iterable<String>} for
 * type {@code Iterable<Integer>}, the map won't be able to detect and throw type error.
 *

              restoreInterruptIfIsInterruptedException(e);
              logger.get().log(WARNING, "thrown by close()", e);
            }
          });
    } catch (RejectedExecutionException e) {
      if (logger.get().isLoggable(WARNING)) {
        logger
            .get()
            .log(
                WARNING,
                String.format("while submitting close to %s; will close inline", executor),

[tool.coverage.report]
show_missing = true
sort = "-Cover"

[tool.coverage.html]
show_contexts = true

[tool.ruff.lint]
select = [
    "E",  # pycodestyle errors
    "W",  # pycodestyle warnings
    "F",  # pyflakes
    "I",  # isort
    "B",  # flake8-bugbear
    "C4",  # flake8-comprehensions
    "UP",  # pyupgrade
]
ignore = [
    "E501",  # line too long, handled by black

        if (ageMillis + minFreshMillis >= freshMillis) {
          builder.addHeader("Warning", "110 HttpURLConnection \"Response is stale\"")
        }
        val oneDayMillis = 24 * 60 * 60 * 1000L
        if (ageMillis > oneDayMillis && isFreshnessLifetimeHeuristic()) {
          builder.addHeader("Warning", "113 HttpURLConnection \"Heuristic expiration\"")
        }
        return CacheStrategy(null, builder.build())

   * more futures or adding more {@code directExecutor()} listeners inline -- consider {@link
   * MoreExecutors#directExecutor}. Otherwise, avoid it: See the warnings on the docs for {@code
   * directExecutor}.
   *
   * <p>This is the most general listener interface. For common operations performed using

   * more futures or adding more {@code directExecutor()} listeners inline -- consider {@link
   * MoreExecutors#directExecutor}. Otherwise, avoid it: See the warnings on the docs for {@code
   * directExecutor}.
   *
   * <p>This is the most general listener interface. For common operations performed using

      for (index in 0 until cachedHeaders.size) {
        val fieldName = cachedHeaders.name(index)
        val value = cachedHeaders.value(index)
        if ("Warning".equals(fieldName, ignoreCase = true) && value.startsWith("1")) {
          // Drop 100-level freshness warnings.
          continue
        }
        if (isContentSpecificHeader(fieldName) ||
          !isEndToEnd(fieldName) ||
          networkHeaders[fieldName] == null

            Path mvnDir = tempDir.resolve(".mvn");
            assertTrue(
                    Files.exists(mvnDir),
                    ".mvn directory should be created for 4.1.0 upgrade to avoid root directory warnings");
        }
    }

    @Nested
    @DisplayName("Check vs Apply Behavior")
    class CheckVsApplyTests {

        @Test
        @DisplayName("check goal should not modify files")

-   [guava-discuss: For open-ended questions and discussion](https://groups.google.com/group/guava-discuss)

## IMPORTANT WARNINGS

1.  APIs marked with the `@Beta` annotation at the class or method level are
    subject to change. They can be modified in any way, or even removed, at any