Class TruthFailureSubject

java.lang.Object

com.google.common.truth.Subject

com.google.common.truth.ThrowableSubject

com.google.common.truth.TruthFailureSubject

public final class TruthFailureSubject
extends ThrowableSubject

A subject for AssertionError objects thrown by Truth. TruthFailureSubject contains methods for asserting about the individual "facts" of those failures. This allows tests to avoid asserting about the same fact more often than necessary, including avoiding asserting about facts that are set by other subjects that the main subject delegates to. This keeps tests shorter and less fragile.

To create an instance, call ExpectFailure.assertThat(AssertionError). Or, if you're using a custom message or failure strategy, pass truthFailures() to your about(...) call.

This class accepts any AssertionError value, but it will throw an exception if a caller tries to access the facts of an error that wasn't produced by Truth.

Nested Class Summary

Nested classes/interfaces inherited from class Subject

Subject.Factory<SubjectT,ActualT>

Modifier and Type	Class	Description
static interface	Subject.Factory<SubjectT extends Subject, ActualT>	In a fluent assertion chain, the argument to the common overload of about, the method that specifies what kind of Subject to create.

Method Summary

Modifier and Type	Method	Description
IterableSubject	factKeys()	Returns a subject for the list of fact keys.
StringSubject	factValue(@Nullable String key)	Returns a subject for the value with the given name.
StringSubject	factValue(@Nullable String key, int index)	Returns a subject for the value of the index-th instance of the fact with the given name.
static Subject.Factory<TruthFailureSubject, AssertionError>	truthFailures()	Factory for creating TruthFailureSubject instances.

Methods inherited from class ThrowableSubject

hasCauseThat, hasMessageThat

Modifier and Type	Method	Description
final ThrowableSubject	hasCauseThat()	Returns a new ThrowableSubject to make assertions on the direct cause of the Throwable.
final StringSubject	hasMessageThat()	Returns a StringSubject to make assertions about the message of the Throwable.

Methods inherited from class Subject

actualCustomStringRepresentation, check, equals, failWithActual, failWithActual, failWithoutActual, hashCode, ignoreCheck, isAnyOf, isEqualTo, isIn, isInstanceOf, isNoneOf, isNotEqualTo, isNotIn, isNotInstanceOf, isNotNull, isNotSameInstanceAs, isNull, isSameInstanceAs, toString

Modifier and Type	Method	Description
protected String	actualCustomStringRepresentation()	Returns a string representation of the actual value for inclusion in failure messages.
protected final StandardSubjectBuilder	check(String format, @Nullable Object... args)	Returns a builder for creating a derived subject.
final boolean	equals(@Nullable Object other)	Deprecated. Object.equals(Object) is not supported on Truth subjects.
protected final void	failWithActual(Fact first, Fact... rest)	Fails, reporting a message with the given facts, followed by an automatically added fact of the form: but was: actual value.
protected final void	failWithActual(String key, @Nullable Object value)	Fails, reporting a message with two "facts": key: value but was: actual value.
protected final void	failWithoutActual(Fact first, Fact... rest)	Fails, reporting a message with the given facts, without automatically adding the actual value.
final int	hashCode()	Deprecated. Object.hashCode() is not supported on Truth subjects.
protected final StandardSubjectBuilder	ignoreCheck()	Begins a new call chain that ignores any failures.
void	isAnyOf(@Nullable Object first, @Nullable Object second, @Nullable Object... rest)	Checks that the value under test is equal to any of the given elements.
void	isEqualTo(@Nullable Object expected)	Checks that the value under test is equal to the given object.
void	isIn(@Nullable Iterable<?> iterable)	Checks that the value under test is equal to any element in the given iterable.
void	isInstanceOf(@Nullable Class<?> clazz)	Checks that the value under test is an instance of the given class.
void	isNoneOf(@Nullable Object first, @Nullable Object second, @Nullable Object... rest)	Checks that the value under test is not equal to any of the given elements.
void	isNotEqualTo(@Nullable Object other)	Checks that the value under test is not equal to the given object.
void	isNotIn(@Nullable Iterable<?> iterable)	Checks that the value under test is not equal to any element in the given iterable.
void	isNotInstanceOf(@Nullable Class<?> clazz)	Checks that the value under test is not an instance of the given class.
void	isNotNull()	Checks that the value under test is not null.
final void	isNotSameInstanceAs(@Nullable Object other)	Checks that the value under test is not the same instance as the given object.
void	isNull()	Checks that the value under test is null.
final void	isSameInstanceAs(@Nullable Object expected)	Checks that the value under test is the same instance as the given object.
String	toString()	Deprecated. Object.toString() is not supported on Truth subjects.

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Details

truthFailures

public static Subject.Factory<TruthFailureSubject, AssertionError> truthFailures()

Factory for creating TruthFailureSubject instances. Most users will just use ExpectFailure.assertThat(AssertionError).

factKeys

public IterableSubject factKeys()

Returns a subject for the list of fact keys.

factValue

public StringSubject factValue(@Nullable String key)

Returns a subject for the value with the given name.

The value is always a string, the String.valueOf representation of the value passed to Fact.fact(String, Object).

The value is never null:

• In the case of facts that have no value, factValue throws an exception. To test for such facts, use factKeys() .contains(...) or a similar method.
• In the case of facts that have a value that is rendered as "null" (such as those created with fact("key", null)), factValue considers them have a string value, the string "null."

If the failure under test contains more than one fact with the given key, this method will fail the test. To assert about such a failure, use the other overload of factValue.

factValue

public StringSubject factValue(@Nullable String key,
 int index)

Returns a subject for the value of the index-th instance of the fact with the given name. Most Truth failures do not contain multiple facts with the same key, so most tests should use the other overload of factValue.