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How to use getOnlyConstructor method of com.tngtech.jgiven.junit.JGivenMethodRule class

Best JGiven code snippet using com.tngtech.jgiven.junit.JGivenMethodRule.getOnlyConstructor

Source:JGivenMethodRule.java

...103        if( JUNITPARAMS_STATEMENT.equals( base.getClass().getCanonicalName() ) ) {104            arguments = getArgumentsFrom( base, "params" );105        }106        if( isParameterizedTest( target ) ) {107            Constructor<?> constructor = getOnlyConstructor( target.getClass() );108            constructorOrMethod = constructor;109            arguments = getArgumentsFrom( constructor, target );110        }111        return ParameterNameUtil.mapArgumentsWithParameterNames( constructorOrMethod, arguments );112    }113    private static List<Object> getArgumentsFrom( Object object, String fieldName ) {114        Class<?> methodClass = object.getClass();115        try {116            Field field = methodClass.getDeclaredField( fieldName );117            field.setAccessible( true );118            return Arrays.asList( (Object[]) field.get( object ) );119        } catch( NoSuchFieldException e ) {120            log.warn( format( "Could not find field containing test method arguments in '%s'. "121                    + "Probably the internal representation has changed. Consider writing a bug report.",122                methodClass.getSimpleName() ), e );123        } catch( IllegalAccessException e ) {124            log.warn( format( "Not able to access field containing test method arguments in '%s'. "125                    + "Probably the internal representation has changed. Consider writing a bug report.",126                methodClass.getSimpleName() ), e );127        }128        return Collections.emptyList();129    }130    private static boolean isParameterizedTest( Object target ) {131        RunWith runWith = target.getClass().getAnnotation( RunWith.class );132        return runWith != null && Parameterized.class.equals( runWith.value() );133    }134    private static Constructor<?> getOnlyConstructor( Class<?> testClass ) {135        Constructor<?>[] constructors = testClass.getConstructors();136        if( constructors.length != 1 ) {137            log.warn( "Test class can only have one public constructor, "138                    + "see org.junit.runners.Parameterized.TestClassRunnerForParameters.validateConstructor(List<Throwable>)" );139        }140        return constructors[0];141    }142    /**143     * Searches for all arguments of the given {@link Parameterized} test class by retrieving the values of all144     * non-static instance fields and comparing their types with the constructor arguments. The order of resulting145     * parameters corresponds to the order of the constructor argument types (which is equal to order of the provided146     * data of the method annotated with {@link Parameterized}). If the constructor contains multiple arguments of the same147     * type, the order of {@link ReflectionUtil#getAllNonStaticFieldValuesFrom(Class, Object, String)} is used.148     *...

getOnlyConstructor

Using AI Code Generation

1    public static JGivenMethodRule getOnlyConstructor(Class<?> clazz) {2        for (Constructor<?> constructor : clazz.getDeclaredConstructors()) {3            if (constructor.getParameterCount() > 0) {4                continue;5            }6            try {7                constructor.setAccessible(true);8                return new JGivenMethodRule(constructor.newInstance());9            } catch (IllegalAccessException | InstantiationException | InvocationTargetException e) {10                throw new RuntimeException(e);11            }12        }13        throw new RuntimeException("Could not find constructor for class: " + clazz);14    }15}16JGivenMethodRule jGivenMethodRule = JGivenMethodRule.getOnlyConstructor(StepClass.class);17jGivenMethodRule.apply(new Statement() {18    public void evaluate() throws Throwable {19        StepClass stepClass = jGivenMethodRule.getTestInstance();20        stepClass.whenIHaveAParameterizedMethod("test");21        stepClass.thenTheMethodIsCalled();22    }23}, null).evaluate();24JGivenMethodRule jGivenMethodRule = JGivenMethodRule.getOnlyConstructor(StepClass.class);25jGivenMethodRule.apply(new Statement() {26    public void evaluate() throws Throwable {27        StepClass stepClass = jGivenMethodRule.getTestInstance();28        stepClass.whenIHaveAParameterizedMethod("test");29        stepClass.thenTheMethodIsCalled();30    }31}, null).evaluate();32JGivenMethodRule jGivenMethodRule = JGivenMethodRule.getOnlyConstructor(StepClass.class);

getOnlyConstructor

Using AI Code Generation

1public class JGivenMethodRule extends MethodRule {2    public Statement apply( final Statement base, FrameworkMethod method, Object target ) {3        if ( !isScenarioMethod( method ) ) {4            return base;5        }6        return new Statement() {7            public void evaluate() throws Throwable {8                getOnlyConstructor( target.getClass() ).newInstance( target );9                base.evaluate();10            }11        };12    }13    private boolean isScenarioMethod( FrameworkMethod method ) {14        return method.getAnnotation( ScenarioTest.class ) != null;15    }16    private Constructor<?> getOnlyConstructor( Class<?> clazz ) {17        Constructor<?>[] constructors = clazz.getDeclaredConstructors();18        if ( constructors.length != 1 ) {19            throw new IllegalArgumentException( "Class must have exactly one constructor" );20        }21        return constructors[0];22    }23}24@RunWith( JGivenClassRule.class )25public class JGivenTest {26    public JGivenMethodRule methodRule = new JGivenMethodRule();27    public void scenarioTest() {28        given().a_value( 1 );29        when().the_value_is_incremented();30        then().the_value_is( 2 );31    }32    public static class Stage {33        private int value;34        public Stage a_value( int value ) {35            this.value = value;36            return self();37        }38        public Stage the_value_is_incremented() {39            value++;40            return self();41        }42        public Stage the_value_is( int expectedValue ) {43            assertThat( value ).isEqualTo( expectedValue );44            return self();45        }46        private Stage self() {47            return this;48        }49    }50}

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