# Testing a Database

!!! info
    These docs are about to be updated. 🎉

    The current version assumes Pydantic v1, and SQLAlchemy versions less than 2.0.

    The new docs will include Pydantic v2 and will use <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a> (which is also based on SQLAlchemy) once it is updated to use Pydantic v2 as well.

    return List(elements.size / 2) { Header(elements[it * 2]!!, elements[it * 2 + 1]!!) }
  }

  @JvmStatic
  fun repeat(
    c: Char,
    count: Int,
  ): String {
    val array = CharArray(count)
    Arrays.fill(array, c)
    return String(array)
  }

  /**
   * Okio buffers are internally implemented as a linked list of arrays. Usually this implementation

  }

  private static String newTestString(Random random, BitSet bitSet, int percentMatching) {
    final String allMatchingChars = allMatchingChars(bitSet);
    final char[] result = new char[STRING_LENGTH];
    // Fill with matching chars.
    for (int i = 0; i < result.length; i++) {
      result[i] = allMatchingChars.charAt(random.nextInt(allMatchingChars.length()));
    }
    // Replace some of chars by non-matching.

  }

  private static String newTestString(Random random, BitSet bitSet, int percentMatching) {
    final String allMatchingChars = allMatchingChars(bitSet);
    final char[] result = new char[STRING_LENGTH];
    // Fill with matching chars.
    for (int i = 0; i < result.length; i++) {
      result[i] = allMatchingChars.charAt(random.nextInt(allMatchingChars.length()));
    }
    // Replace some of chars by non-matching.

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   * multiset itself).
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *
   * <p>This method is not type-safe, as it may be called on elements that are not mutually
   * comparable.
   *

  private void assertCleanup(
      LoadingCache<Integer, String> cache,
      CountingRemovalListener<Integer, String> removalListener) {

    // initialSize will most likely be 2, but it's possible for the GC to have already run, so we'll
    // observe a size of 1
    long initialSize = cache.size();
    assertTrue(initialSize == 1 || initialSize == 2);

    // wait up to 5s

  private void assertCleanup(
      LoadingCache<Integer, String> cache,
      CountingRemovalListener<Integer, String> removalListener) {

    // initialSize will most likely be 2, but it's possible for the GC to have already run, so we'll
    // observe a size of 1
    long initialSize = cache.size();
    assertTrue(initialSize == 1 || initialSize == 2);

    // wait up to 5s

  int componentLength;

  private Iterable<String> components;

  @BeforeExperiment
  void setUp() {
    String component = Strings.repeat("a", componentLength);
    String[] raw = new String[count];
    Arrays.fill(raw, component);
    components = Arrays.asList(raw);
  }

  /** {@link Joiner} with a string delimiter. */
  @Benchmark
  int joinerWithStringDelimiter(int reps) {
    int dummy = 0;

      delegate.clear(); // invalidate any iterators left over!
      table = null;
      size = 0;
    } else {
      Arrays.fill(requireElements(), 0, size, null);
      CompactHashing.tableClear(requireTable());
      Arrays.fill(requireEntries(), 0, size, 0);
      this.size = 0;
    }
  }

  @J2ktIncompatible
  private void writeObject(ObjectOutputStream stream) throws IOException {