### Question:
MetaInject extends BaseStep implements StepInterface { static Set<String> convertToUpperCaseSet( String[] array ) { if ( array == null ) { return Collections.emptySet(); } Set<String> strings = new HashSet<String>(); for ( String currentString : array ) { strings.add( currentString.toUpperCase() ); } return strings; } MetaInject(
    StepMeta stepMeta, StepDataInterface stepDataInterface, int copyNr, TransMeta transMeta, Trans trans ); boolean processRow( StepMetaInterface smi, StepDataInterface sdi ); boolean init( StepMetaInterface smi, StepDataInterface sdi ); static void removeUnavailableStepsFromMapping( Map<TargetStepAttribute, SourceStepField> targetMap,
                                                        Set<SourceStepField> unavailableSourceSteps, Set<TargetStepAttribute> unavailableTargetSteps ); static Set<TargetStepAttribute> getUnavailableTargetSteps( Map<TargetStepAttribute, SourceStepField> targetMap,
                                                                    TransMeta injectedTransMeta ); static Set<TargetStepAttribute> getUnavailableTargetKeys( Map<TargetStepAttribute, SourceStepField> targetMap,
                                                                   TransMeta injectedTransMeta, Set<TargetStepAttribute> unavailableTargetSteps ); static Set<SourceStepField> getUnavailableSourceSteps( Map<TargetStepAttribute, SourceStepField> targetMap,
                                                                TransMeta sourceTransMeta, StepMeta stepMeta );  }### Answer:
@Test public void convertToUpperCaseSet_null_array() { Set<String> actualResult = MetaInject.convertToUpperCaseSet( null ); assertNotNull( actualResult ); assertTrue( actualResult.isEmpty() ); }
@Test public void convertToUpperCaseSet() { String[] input = new String[] { "Test_Step", "test_step1" }; Set<String> actualResult = MetaInject.convertToUpperCaseSet( input ); Set<String> expectedResult = new HashSet<>(); expectedResult.add( "TEST_STEP" ); expectedResult.add( "TEST_STEP1" ); assertEquals( expectedResult, actualResult ); }