Existem alguns cenários onde você deseje sobrepor uma dependência durante os testes.

Você não quer que a dependência original execute (e nenhuma das subdependências que você possa ter).

Em vez disso, você deseja fornecer uma dependência diferente que será usada somente durante os testes (possivelmente apenas para alguns testes específicos) e fornecerá um valor que pode ser usado onde o valor da dependência original foi usado.

    Iterator<Subscriber> one = registry.getSubscribers("");
    assertEquals(s1, one.next().target);
    assertFalse(one.hasNext());

    one = registry.getSubscribers("");

    registry.register(s2);
    registry.register(o1);

    Iterator<Subscriber> three = registry.getSubscribers("");
    assertEquals(s1, one.next().target);
    assertFalse(one.hasNext());

    worked everywhere that I know of except for one place: when running the GWT
    util.concurrent tests under Guava.

    The problem is that GWT responds poorly to two .gwt.xml files in the same
    Java package; see
    https://groups.google.com/g/google-web-toolkit-contributors/c/CqYH59Dt_rQ/m/uVGW1QdUsXUJ
    for details.

    The summary is that it ignores one file in favor of the other.

 */

package com.google.common.collect.testing.google;

import static com.google.common.collect.testing.Helpers.mapEntry;
import static com.google.common.collect.testing.features.CollectionSize.ONE;
import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;

  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testCreateWithDuplicates_nullDuplicatesNotRejected() {
    expectFirstRemoved(getEntriesMultipleNullKeys());
  }

  @MapFeature.Require(absent = REJECTS_DUPLICATES_AT_CREATION)
  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testCreateWithDuplicates_nonNullDuplicatesNotRejected() {

environment.title = Production

# Does it enable the Framework internal debug? (true only when emergency)
framework.debug = false

# one day: 86400000, three days: 259200000, five days: 432000000, one week: 604800000, one year: 31556926000
# special script :: absolute mode: $(2014/07/10), relative mode: addDay(3).addMonth(4)

    new EqualsTester()
        .addEqualityGroup(
            RemovalNotification.create("one", 1, RemovalCause.EXPLICIT),
            RemovalNotification.create("one", 1, RemovalCause.REPLACED))
        .addEqualityGroup(RemovalNotification.create("1", 1, RemovalCause.EXPLICIT))
        .addEqualityGroup(RemovalNotification.create("one", 2, RemovalCause.EXPLICIT))
        .testEquals();
  }

      0xFFFF - 0x0800 + 1 - THREE_BYTE_SURROGATES;

  // 2,650,112
  private static final long EXPECTED_THREE_BYTE_ROUNDTRIPPABLE_COUNT =
      // All one byte characters
      (long) Math.pow(EXPECTED_ONE_BYTE_ROUNDTRIPPABLE_COUNT, 3)
          +
          // One two byte character and a one byte character
          2 * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Three byte characters

environment.title = Production

# Does it enable the Framework internal debug? (true only when emergency)
framework.debug = false

# one day: 86400000, three days: 259200000, five days: 432000000, one week: 604800000, one year: 31556926000
# special script :: absolute mode: $(2014/07/10), relative mode: addDay(3).addMonth(4)

environment.title = Production

# Does it enable the Framework internal debug? (true only when emergency)
framework.debug = false

# one day: 86400000, three days: 259200000, five days: 432000000, one week: 604800000, one year: 31556926000
# special script :: absolute mode: $(2014/07/10), relative mode: addDay(3).addMonth(4)