| Class | CapturingDebugger | Undocumented | 
| Class | CapturingReporter | Reporter that keeps a log of all actions performed on it. | 
| Class | TrialRunnerTestsMixin | Mixin defining tests for runner.TrialRunner. | 
| Class | TrialRunnerTests | Tests for runner.TrialRunnerwith the feature to turn unclean errors into warnings disabled. | 
| Class | TrialRunnerWithUncleanWarningsReporterTests | Tests for the TrialRunner's interaction with an unclean-error suppressing reporter. | 
| Class | DryRunMixin | Mixin for testing that 'dry run' mode works with various pyunit.TestCasesubclasses. | 
| Class | SynchronousDryRunTests | Check that 'dry run' mode works well with trial's SynchronousTestCase. | 
| Class | DryRunTests | Check that 'dry run' mode works well with Trial tests. | 
| Class | PyUnitDryRunTests | Check that 'dry run' mode works well with stdlib unittest tests. | 
| Class | RunnerTests | No class docstring; 9/18 methods documented | 
| Class | TrialSuiteTests | Undocumented | 
| Class | UntilFailureTests | No class docstring; 1/1 classes, 4/5 methods documented | 
| Class | UncleanUntilFailureTests | Test that the run-until-failure feature works correctly with the unclean error suppressor. | 
| Class | BreakingSuite | A TestSuitethat logs an error when it is run. | 
| Class | LoggedErrorsTests | No summary | 
| Class | TestHolderTests | No class docstring; 3/4 methods documented | 
| Class | ErrorHolderTestsMixin | This mixin defines test methods which can be applied to a runner.ErrorHolderconstructed with either aFailureor aexc_info-style tuple. | 
| Class | FailureHoldingErrorHolderTests | Tests for runner.ErrorHolderbehaving similarly torunner.TestHolderwhen constructed with aFailurerepresenting its error. | 
| Class | ExcInfoHoldingErrorHolderTests | Tests for runner.ErrorHolderbehaving similarly torunner.TestHolderwhen constructed with aexc_info-style tuple representing its 
error. | 
| Class | MalformedMethodTests | Test that trial manages when test methods don't have correct signatures. | 
| Class | DestructiveTestSuiteTests | Test for runner.DestructiveTestSuite. | 
| Class | RunnerDeprecationTests | No class docstring; 1/1 classes, 1/1 methods documented | 
| Class | QualifiedNameWalkerTests | Tests for twisted.trial.runner._qualNameWalker. | 
| Class | TrialMainDoesNothingTests | Importing twisted.trial.__main__will not run the script unless it is actually__main__. |