### Question:
JavaccSourceFileCompiler implements SourceFileCompiler { @Override public void cleanTempOutputDirectory() { FileUtils.deleteQuietly(configuration.getTempOutputDirectory()); } JavaccSourceFileCompiler(ProgramInvoker programInvoker, ProgramArguments argumentsProvidedByTask, CompilerInputOutputConfiguration configuration, Logger logger); @Override void compileSourceFilesToTempOutputDirectory(); @Override void copyNonJavaccFilesToOutputDirectory(); @Override void compile(File inputDirectory, RelativePath inputRelativePath); @Override void copyCompiledFilesFromTempOutputDirectoryToOutputDirectory(); @Override String supportedSuffix(); @Override String getProgramName(); @Override File getOutputDirectory(); @Override File getInputDirectory(); @Override void createTempOutputDirectory(); @Override void cleanTempOutputDirectory(); @Override Logger getLogger();  }### Answer:
@Test public void cleanTempOutputDirectoryDeletesDirectory() { compiler.cleanTempOutputDirectory(); assertFalse(compilerInputOutputConfiguration.getTempOutputDirectory().exists()); }