Class IterableSubject.UsingCorrespondence<A,E>

java.lang.Object
com.google.common.truth.IterableSubject.UsingCorrespondence<A,E>
Direct Known Subclasses:
PrimitiveDoubleArraySubject.DoubleArrayAsIterable, PrimitiveFloatArraySubject.FloatArrayAsIterable
Enclosing class:
IterableSubject

public static class IterableSubject.UsingCorrespondence<A,E> extends Object
A partially specified check in which the actual elements (normally the elements of the Iterable under test) are compared to expected elements using a Correspondence. The expected elements are of type E. Call methods on this object to actually execute the check.
  • Field Details

  • Constructor Details

  • Method Details

    • displayingDiffsPairedBy

      public IterableSubject.UsingCorrespondence<A,E> displayingDiffsPairedBy(com.google.common.base.Function<? super E,?> keyFunction)
      Specifies a way to pair up unexpected and missing elements in the message when an assertion fails. For example:
      
       assertThat(actualRecords)
           .comparingElementsUsing(RECORD_CORRESPONDENCE)
           .displayingDiffsPairedBy(Record::getId)
           .containsExactlyElementsIn(expectedRecords);
       

      Important: The {code keyFunction} function must be able to accept both the actual and the unexpected elements, i.e. it must satisfy Function<? super A, ?> as well as Function<? super E, ?>. If that constraint is not met then a subsequent method may throw ClassCastException. Use the two-parameter overload if you need to specify different key functions for the actual and expected elements.

      On assertions where it makes sense to do so, the elements are paired as follows: they are keyed by keyFunction, and if an unexpected element and a missing element have the same non-null key then the they are paired up. (Elements with null keys are not paired.) The failure message will show paired elements together, and a diff will be shown if the Correspondence.formatDiff(A, E) method returns non-null.

      The expected elements given in the assertion should be uniquely keyed by keyFunction. If multiple missing elements have the same key then the pairing will be skipped.

      Useful key functions will have the property that key equality is less strict than the correspondence, i.e. given actual and expected values with keys actualKey and expectedKey, if correspondence.compare(actual, expected) is true then it is guaranteed that actualKey is equal to expectedKey, but there are cases where actualKey is equal to expectedKey but correspondence.compare(actual, expected) is false.

      If the apply method on the key function throws an exception then the element will be treated as if it had a null key and not paired. (The first such exception will be noted in the failure message.)

      Note that calling this method makes no difference to whether a test passes or fails, it just improves the message if it fails.

    • displayingDiffsPairedBy

      public IterableSubject.UsingCorrespondence<A,E> displayingDiffsPairedBy(com.google.common.base.Function<? super A,?> actualKeyFunction, com.google.common.base.Function<? super E,?> expectedKeyFunction)
      Specifies a way to pair up unexpected and missing elements in the message when an assertion fails. For example:
      
       assertThat(actualFoos)
           .comparingElementsUsing(FOO_BAR_CORRESPONDENCE)
           .displayingDiffsPairedBy(Foo::getId, Bar::getFooId)
           .containsExactlyElementsIn(expectedBar);
       

      On assertions where it makes sense to do so, the elements are paired as follows: the unexpected elements are keyed by actualKeyFunction, the missing elements are keyed by expectedKeyFunction, and if an unexpected element and a missing element have the same non-null key then the they are paired up. (Elements with null keys are not paired.) The failure message will show paired elements together, and a diff will be shown if the Correspondence.formatDiff(A, E) method returns non-null.

      The expected elements given in the assertion should be uniquely keyed by expectedKeyFunction. If multiple missing elements have the same key then the pairing will be skipped.

      Useful key functions will have the property that key equality is less strict than the correspondence, i.e. given actual and expected values with keys actualKey and expectedKey, if correspondence.compare(actual, expected) is true then it is guaranteed that actualKey is equal to expectedKey, but there are cases where actualKey is equal to expectedKey but correspondence.compare(actual, expected) is false.

      If the apply method on either of the key functions throws an exception then the element will be treated as if it had a null key and not paired. (The first such exception will be noted in the failure message.)

      Note that calling this method makes no difference to whether a test passes or fails, it just improves the message if it fails.

    • contains

      public void contains(E expected)
      Checks that the subject contains at least one element that corresponds to the given expected element.
    • doesNotContain

      public void doesNotContain(E excluded)
      Checks that none of the actual elements correspond to the given element.
    • containsExactly

      @SafeVarargs public final Ordered containsExactly(E... expected)
      Checks that subject contains exactly elements that correspond to the expected elements, i.e. that there is a 1:1 mapping between the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method.

      To test that the iterable contains the elements corresponding to those in an array, prefer containsExactlyElementsIn(Object[]). It makes clear that the given array is a list of elements, not an element itself. This helps human readers and avoids a compiler warning.

    • containsExactlyElementsIn

      public Ordered containsExactlyElementsIn(Iterable<? extends E> expected)
      Checks that subject contains exactly elements that correspond to the expected elements, i.e. that there is a 1:1 mapping between the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method.

    • containsExactlyElementsIn

      public Ordered containsExactlyElementsIn(E[] expected)
      Checks that subject contains exactly elements that correspond to the expected elements, i.e. that there is a 1:1 mapping between the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method.

    • correspondInOrderExactly

      private boolean correspondInOrderExactly(Iterator<? extends A> actual, Iterator<? extends E> expected)
      Returns whether the actual and expected iterators have the same number of elements and, when iterated pairwise, every pair of actual and expected values satisfies the correspondence. Returns false if any comparison threw an exception.
    • findCandidateMapping

      private com.google.common.collect.ImmutableSetMultimap<Integer,Integer> findCandidateMapping(List<? extends A> actual, List<? extends E> expected, Correspondence.ExceptionStore exceptions)
      Given a list of actual elements and a list of expected elements, finds a many:many mapping between actual and expected elements where a pair of elements maps if it satisfies the correspondence. Returns this mapping as a multimap where the keys are indexes into the actual list and the values are indexes into the expected list. Any exceptions are treated as if the elements did not correspond, and the exception added to the store.
    • failIfCandidateMappingHasMissingOrExtra

      private boolean failIfCandidateMappingHasMissingOrExtra(List<? extends A> actual, List<? extends E> expected, com.google.common.collect.ImmutableSetMultimap<Integer,Integer> mapping, Correspondence.ExceptionStore exceptions)
      Given a list of actual elements, a list of expected elements, and a many:many mapping between actual and expected elements specified as a multimap of indexes into the actual list to indexes into the expected list, checks that every actual element maps to at least one expected element and vice versa, and fails if this is not the case. Returns whether the assertion failed.
    • describeMissingOrExtra

      private String describeMissingOrExtra(List<? extends E> missing, List<? extends A> extra, Correspondence.ExceptionStore exceptions)
      Given a list of missing elements and a list of extra elements, at least one of which must be non-empty, returns a verb phrase (suitable for appearing after the subject of the verb) describing them. Exceptions from calling Correspondence.formatDiff(A, E) are stored in exceptions.
    • describeMissingOrExtraWithoutPairing

      private String describeMissingOrExtraWithoutPairing(String verb, List<? extends E> missing, List<? extends A> extra)
    • describeMissingOrExtraWithPairing

      private String describeMissingOrExtraWithPairing(IterableSubject.UsingCorrespondence<A,E>.Pairing pairing, Correspondence.ExceptionStore exceptions)
    • formatExtras

      private Facts formatExtras(String label, E missing, List<? extends A> extras, Correspondence.ExceptionStore exceptions)
    • formatExtrasInline

      private List<Object> formatExtrasInline(E missing, List<? extends A> extras, Correspondence.ExceptionStore exceptions)
    • findNotIndexed

      private <T> List<T> findNotIndexed(List<T> list, Set<Integer> indexes)
      Returns all the elements of the given list other than those with the given indexes. Assumes that all the given indexes really are valid indexes into the list.
    • formatMissing

      private String formatMissing(List<?> missing)
      Returns a description of the missing items suitable for inclusion in failure messages. If there is a single item, returns "<item>". Otherwise, returns "each of <[item, item, item]>".
    • findMaximalOneToOneMapping

      private com.google.common.collect.ImmutableBiMap<Integer,Integer> findMaximalOneToOneMapping(com.google.common.collect.ImmutableMultimap<Integer,Integer> edges)
      Given a many:many mapping between actual elements and expected elements, finds a 1:1 mapping which is the subset of that many:many mapping which includes the largest possible number of elements. The input and output mappings are each described as a map or multimap where the keys are indexes into the actual list and the values are indexes into the expected list. If there are multiple possible output mappings tying for the largest possible, this returns an arbitrary one.
    • failIfOneToOneMappingHasMissingOrExtra

      private boolean failIfOneToOneMappingHasMissingOrExtra(List<? extends A> actual, List<? extends E> expected, com.google.common.collect.BiMap<Integer,Integer> mapping, Correspondence.ExceptionStore exceptions)
      Given a list of actual elements, a list of expected elements, and a 1:1 mapping between actual and expected elements specified as a bimap of indexes into the actual list to indexes into the expected list, checks that every actual element maps to an expected element and vice versa, and fails if this is not the case. Returns whether the assertion failed.
    • containsAtLeast

      @SafeVarargs public final Ordered containsAtLeast(E first, E second, E... rest)
      Checks that the subject contains elements that corresponds to all of the expected elements, i.e. that there is a 1:1 mapping between any subset of the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method. The elements must appear in the given order within the subject, but they are not required to be consecutive.

    • containsAtLeastElementsIn

      public Ordered containsAtLeastElementsIn(Iterable<? extends E> expected)
      Checks that the subject contains elements that corresponds to all of the expected elements, i.e. that there is a 1:1 mapping between any subset of the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method. The elements must appear in the given order within the subject, but they are not required to be consecutive.

    • containsAtLeastElementsIn

      public Ordered containsAtLeastElementsIn(E[] expected)
      Checks that the subject contains elements that corresponds to all of the expected elements, i.e. that there is a 1:1 mapping between any subset of the actual elements and the expected elements where each pair of elements correspond.

      To also test that the contents appear in the given order, make a call to inOrder() on the object returned by this method. The elements must appear in the given order within the subject, but they are not required to be consecutive.

    • correspondInOrderAllIn

      private boolean correspondInOrderAllIn(Iterator<? extends A> actual, Iterator<? extends E> expected)
      Returns whether all the elements of the expected iterator and any subset of the elements of the actual iterator can be paired up in order, such that every pair of actual and expected elements satisfies the correspondence. Returns false if any comparison threw an exception.
    • findCorresponding

      private boolean findCorresponding(Iterator<? extends A> actual, E expectedElement, Correspondence.ExceptionStore exceptions)
      Advances the actual iterator looking for an element which corresponds to the expected element. Returns whether or not it finds one.
    • failIfCandidateMappingHasMissing

      private boolean failIfCandidateMappingHasMissing(List<? extends A> actual, List<? extends E> expected, com.google.common.collect.ImmutableSetMultimap<Integer,Integer> mapping, Correspondence.ExceptionStore exceptions)
      Given a list of actual elements, a list of expected elements, and a many:many mapping between actual and expected elements specified as a multimap of indexes into an actual list to indexes into the expected list, checks that every expected element maps to at least one actual element, and fails if this is not the case. Actual elements which do not map to any expected elements are ignored.
    • describeMissing

      private String describeMissing(List<? extends E> missing, List<? extends A> extra, Correspondence.ExceptionStore exceptions)
      Given a list of missing elements, which must be non-empty, and a list of extra elements, returns a verb phrase (suitable for appearing after the subject of the verb) describing the missing elements, diffing against the extra ones where appropriate.
    • describeMissingWithoutPairing

      private String describeMissingWithoutPairing(String verb, List<? extends E> missing)
    • describeMissingWithPairing

      private String describeMissingWithPairing(IterableSubject.UsingCorrespondence<A,E>.Pairing pairing, Correspondence.ExceptionStore exceptions)
    • failIfOneToOneMappingHasMissing

      private boolean failIfOneToOneMappingHasMissing(List<? extends A> actual, List<? extends E> expected, com.google.common.collect.BiMap<Integer,Integer> mapping, Correspondence.ExceptionStore exceptions)
      Given a list of expected elements, and a 1:1 mapping between actual and expected elements specified as a bimap of indexes into an actual list to indexes into the expected list, checks that every expected element maps to an actual element. Actual elements which do not map to any expected elements are ignored.
    • containsAnyOf

      @SafeVarargs public final void containsAnyOf(E first, E second, E... rest)
      Checks that the subject contains at least one element that corresponds to at least one of the expected elements.
    • containsAnyIn

      public void containsAnyIn(Iterable<? extends E> expected)
      Checks that the subject contains at least one element that corresponds to at least one of the expected elements.
    • containsAnyIn

      public void containsAnyIn(E[] expected)
      Checks that the subject contains at least one element that corresponds to at least one of the expected elements.
    • containsAny

      private void containsAny(String failVerb, Iterable<? extends E> expected)
    • describeAnyMatchesByKey

      private String describeAnyMatchesByKey(IterableSubject.UsingCorrespondence<A,E>.Pairing pairing, Correspondence.ExceptionStore exceptions)
    • containsNoneOf

      @SafeVarargs public final void containsNoneOf(E firstExcluded, E secondExcluded, E... restOfExcluded)
      Checks that the subject contains no elements that correspond to any of the given elements. (Duplicates are irrelevant to this test, which fails if any of the subject elements correspond to any of the given elements.)
    • containsNoneIn

      public void containsNoneIn(Iterable<? extends E> excluded)
      Checks that the subject contains no elements that correspond to any of the given elements. (Duplicates are irrelevant to this test, which fails if any of the subject elements correspond to any of the given elements.)
    • containsNoneIn

      public void containsNoneIn(E[] excluded)
      Checks that the subject contains no elements that correspond to any of the given elements. (Duplicates are irrelevant to this test, which fails if any of the subject elements correspond to any of the given elements.)
    • containsNone

      private void containsNone(String excludedPrefix, Iterable<? extends E> excluded)
    • getCastActual

      private Iterable<A> getCastActual()