com.google.common.truth

Interface FailureStrategy

public interface FailureStrategy

Defines what to do when a check fails.

This type does not appear directly in a fluent assertion chain, but you choose a FailureStrategy by choosing which method to call at the beginning of the chain.

Built-in strategies include:

• assertions
• expectations
• assumptions
• (and some useful only to people who implement custom subjects, described below)

For more information about the fluent chain, see this FAQ entry.

For people extending Truth

Custom FailureStrategy implementations are unusual. If you think you need one, consider these alternatives:

• To test a custom subject, use ExpectFailure.
• To create subjects for other objects related to your actual value (for chained assertions), use Subject.check(String, Object...), which preserves the existing FailureStrategy and other context.
• To return a no-op subject after a previous assertion has failed (for chained assertions), use Subject.ignoreCheck()

When you really do need to create your own strategy, rather than expose your FailureStrategy instance to users, expose a StandardSubjectBuilder instance using StandardSubjectBuilder.forCustomFailureStrategy(STRATEGY).

Method Summary

Modifier and Type	Method and Description
void	fail(AssertionError failure) Handles a failure.

Method Detail

fail

void fail(AssertionError failure)

Handles a failure. The parameter is an AssertionError or subclass thereof, and it contains information about the failure, which may include:

• message: getMessage()
• cause: getCause()
• actual and expected values: ComparisonFailure.getActual(), ComparisonFailure.getExpected()
• stack trace: Throwable.getStackTrace()

We encourage implementations to record as much of this information as practical in the exceptions they may throw or the other records they may make.