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How to use CreatingMocksWithConstructorTest class of org.mockitousage.constructor package

Best Mockito code snippet using org.mockitousage.constructor.CreatingMocksWithConstructorTest

Source:CreatingMocksWithConstructorTest.java

...10import org.mockito.exceptions.base.MockitoException;11import org.mockito.mock.SerializableMode;12import org.mockitousage.IMethods;13import org.mockitoutil.TestBase;14public class CreatingMocksWithConstructorTest extends TestBase {15    abstract static class AbstractMessage {16        private final String message;17        AbstractMessage() {18            this.message = "hey!";19        }20        AbstractMessage(String message) {21            this.message = message;22        }23        AbstractMessage(int i) {24            this.message = String.valueOf(i);25        }26        String getMessage() {27            return message;28        }29    }30    static class Message extends CreatingMocksWithConstructorTest.AbstractMessage {}31    class InnerClass extends CreatingMocksWithConstructorTest.AbstractMessage {}32    @Test33    public void can_create_mock_with_constructor() {34        CreatingMocksWithConstructorTest.Message mock = Mockito.mock(CreatingMocksWithConstructorTest.Message.class, Mockito.withSettings().useConstructor().defaultAnswer(Mockito.CALLS_REAL_METHODS));35        // the message is a part of state of the mocked type that gets initialized in constructor36        Assert.assertEquals("hey!", mock.getMessage());37    }38    @Test39    public void can_mock_abstract_classes() {40        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor().defaultAnswer(Mockito.CALLS_REAL_METHODS));41        Assert.assertEquals("hey!", mock.getMessage());42    }43    @Test44    public void can_spy_abstract_classes() {45        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.spy(CreatingMocksWithConstructorTest.AbstractMessage.class);46        Assert.assertEquals("hey!", mock.getMessage());47    }48    @Test49    public void can_spy_abstract_classes_with_constructor_args() {50        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor("hello!").defaultAnswer(Mockito.CALLS_REAL_METHODS));51        Assert.assertEquals("hello!", mock.getMessage());52    }53    @Test54    public void can_spy_abstract_classes_with_constructor_primitive_args() {55        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor(7).defaultAnswer(Mockito.CALLS_REAL_METHODS));56        Assert.assertEquals("7", mock.getMessage());57    }58    @Test59    public void can_spy_abstract_classes_with_constructor_array_of_nulls() {60        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor(new Object[]{ null }).defaultAnswer(Mockito.CALLS_REAL_METHODS));61        Assert.assertNull(mock.getMessage());62    }63    @Test64    public void can_spy_abstract_classes_with_casted_null() {65        CreatingMocksWithConstructorTest.AbstractMessage mock = Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor(((String) (null))).defaultAnswer(Mockito.CALLS_REAL_METHODS));66        Assert.assertNull(mock.getMessage());67    }68    @Test69    public void can_spy_abstract_classes_with_null_varargs() {70        try {71            Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor(null).defaultAnswer(Mockito.CALLS_REAL_METHODS));72            Assert.fail();73        } catch (IllegalArgumentException e) {74            assertThat(e).hasMessageContaining(("constructorArgs should not be null. " + "If you need to pass null, please cast it to the right type, e.g.: useConstructor((String) null)"));75        }76    }77    @Test78    public void can_mock_inner_classes() {79        CreatingMocksWithConstructorTest.InnerClass mock = Mockito.mock(CreatingMocksWithConstructorTest.InnerClass.class, Mockito.withSettings().useConstructor().outerInstance(this).defaultAnswer(Mockito.CALLS_REAL_METHODS));80        Assert.assertEquals("hey!", mock.getMessage());81    }82    public static class ThrowingConstructorClass {83        public ThrowingConstructorClass() {84            throw new RuntimeException();85        }86    }87    @Test88    public void explains_constructor_exceptions() {89        try {90            Mockito.mock(CreatingMocksWithConstructorTest.ThrowingConstructorClass.class, Mockito.withSettings().useConstructor().defaultAnswer(Mockito.CALLS_REAL_METHODS));91            Assert.fail();92        } catch (MockitoException e) {93            assertThat(e).hasRootCauseInstanceOf(RuntimeException.class);94            assertThat(e.getCause()).hasMessageContaining("Please ensure the target class has a 0-arg constructor and executes cleanly.");95        }96    }97    static class HasConstructor {98        HasConstructor(String x) {99        }100    }101    @Test102    public void exception_message_when_constructor_not_found() {103        try {104            // when105            Mockito.spy(CreatingMocksWithConstructorTest.HasConstructor.class);106            // then107            Assert.fail();108        } catch (MockitoException e) {109            assertThat(e).hasMessage("Unable to create mock instance of type 'HasConstructor'");110            assertThat(e.getCause()).hasMessageContaining("Please ensure that the target class has a 0-arg constructor.");111        }112    }113    static class Base {}114    static class ExtendsBase extends CreatingMocksWithConstructorTest.Base {}115    static class ExtendsExtendsBase extends CreatingMocksWithConstructorTest.ExtendsBase {}116    static class UsesBase {117        public UsesBase(CreatingMocksWithConstructorTest.Base b) {118            constructorUsed = "Base";119        }120        public UsesBase(CreatingMocksWithConstructorTest.ExtendsBase b) {121            constructorUsed = "ExtendsBase";122        }123        private String constructorUsed = null;124        String getConstructorUsed() {125            return constructorUsed;126        }127    }128    @Test129    public void can_mock_unambigous_constructor_with_inheritance_base_class_exact_match() {130        CreatingMocksWithConstructorTest.UsesBase u = Mockito.mock(CreatingMocksWithConstructorTest.UsesBase.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.Base()).defaultAnswer(Mockito.CALLS_REAL_METHODS));131        Assert.assertEquals("Base", u.getConstructorUsed());132    }133    @Test134    public void can_mock_unambigous_constructor_with_inheritance_extending_class_exact_match() {135        CreatingMocksWithConstructorTest.UsesBase u = Mockito.mock(CreatingMocksWithConstructorTest.UsesBase.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.ExtendsBase()).defaultAnswer(Mockito.CALLS_REAL_METHODS));136        Assert.assertEquals("ExtendsBase", u.getConstructorUsed());137    }138    @Test139    public void can_mock_unambigous_constructor_with_inheritance_non_exact_match() {140        CreatingMocksWithConstructorTest.UsesBase u = Mockito.mock(CreatingMocksWithConstructorTest.UsesBase.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.ExtendsExtendsBase()).defaultAnswer(Mockito.CALLS_REAL_METHODS));141        Assert.assertEquals("ExtendsBase", u.getConstructorUsed());142    }143    static class UsesTwoBases {144        public UsesTwoBases(CreatingMocksWithConstructorTest.Base b1, CreatingMocksWithConstructorTest.Base b2) {145            constructorUsed = "Base,Base";146        }147        public UsesTwoBases(CreatingMocksWithConstructorTest.ExtendsBase b1, CreatingMocksWithConstructorTest.Base b2) {148            constructorUsed = "ExtendsBase,Base";149        }150        public UsesTwoBases(CreatingMocksWithConstructorTest.Base b1, CreatingMocksWithConstructorTest.ExtendsBase b2) {151            constructorUsed = "Base,ExtendsBase";152        }153        private String constructorUsed = null;154        String getConstructorUsed() {155            return constructorUsed;156        }157    }158    @Test159    public void can_mock_unambigous_constructor_with_inheritance_multiple_base_class_exact_match() {160        CreatingMocksWithConstructorTest.UsesTwoBases u = Mockito.mock(CreatingMocksWithConstructorTest.UsesTwoBases.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.Base(), new CreatingMocksWithConstructorTest.Base()).defaultAnswer(Mockito.CALLS_REAL_METHODS));161        Assert.assertEquals("Base,Base", u.getConstructorUsed());162    }163    @Test164    public void can_mock_unambigous_constructor_with_inheritance_first_extending_class_exact_match() {165        CreatingMocksWithConstructorTest.UsesTwoBases u = Mockito.mock(CreatingMocksWithConstructorTest.UsesTwoBases.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.ExtendsBase(), new CreatingMocksWithConstructorTest.Base()).defaultAnswer(Mockito.CALLS_REAL_METHODS));166        Assert.assertEquals("ExtendsBase,Base", u.getConstructorUsed());167    }168    @Test169    public void can_mock_unambigous_constructor_with_inheritance_second_extending_class_exact_match() {170        CreatingMocksWithConstructorTest.UsesTwoBases u = Mockito.mock(CreatingMocksWithConstructorTest.UsesTwoBases.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.Base(), new CreatingMocksWithConstructorTest.ExtendsBase()).defaultAnswer(Mockito.CALLS_REAL_METHODS));171        Assert.assertEquals("Base,ExtendsBase", u.getConstructorUsed());172    }173    @Test174    public void fail_when_multiple_matching_constructors_with_inheritence() {175        try {176            // when177            Mockito.mock(CreatingMocksWithConstructorTest.UsesTwoBases.class, Mockito.withSettings().useConstructor(new CreatingMocksWithConstructorTest.ExtendsBase(), new CreatingMocksWithConstructorTest.ExtendsBase()));178            // then179            Assert.fail();180        } catch (MockitoException e) {181            // TODO the exception message includes Mockito internals like the name of the generated class name.182            // I suspect that we could make this exception message nicer.183            assertThat(e).hasMessage("Unable to create mock instance of type 'UsesTwoBases'");184            assertThat(e.getCause()).hasMessageContaining(("Multiple constructors could be matched to arguments of types " + ("[org.mockitousage.constructor.CreatingMocksWithConstructorTest$ExtendsBase, " + "org.mockitousage.constructor.CreatingMocksWithConstructorTest$ExtendsBase]"))).hasMessageContaining(("If you believe that Mockito could do a better job deciding on which constructor to use, please let us know.\n" + ("Ticket 685 contains the discussion and a workaround for ambiguous constructors using inner class.\n" + "See https://github.com/mockito/mockito/issues/685")));185        }186    }187    @Test188    public void mocking_inner_classes_with_wrong_outer_instance() {189        try {190            // when191            Mockito.mock(CreatingMocksWithConstructorTest.InnerClass.class, Mockito.withSettings().useConstructor().outerInstance(123).defaultAnswer(Mockito.CALLS_REAL_METHODS));192            // then193            Assert.fail();194        } catch (MockitoException e) {195            assertThat(e).hasMessage("Unable to create mock instance of type 'InnerClass'");196            // TODO it would be nice if all useful information was in the top level exception, instead of in the exception's cause197            // also applies to other scenarios in this test198            assertThat(e.getCause()).hasMessageContaining(("Please ensure that the target class has a 0-arg constructor" + " and provided outer instance is correct."));199        }200    }201    @SuppressWarnings({ "CheckReturnValue", "MockitoUsage" })202    @Test203    public void mocking_interfaces_with_constructor() {204        // at the moment this is allowed however we can be more strict if needed205        // there is not much sense in creating a spy of an interface206        Mockito.mock(IMethods.class, Mockito.withSettings().useConstructor());207        Mockito.spy(IMethods.class);208    }209    @Test210    public void prevents_across_jvm_serialization_with_constructor() {211        try {212            // when213            Mockito.mock(CreatingMocksWithConstructorTest.AbstractMessage.class, Mockito.withSettings().useConstructor().serializable(SerializableMode.ACROSS_CLASSLOADERS));214            // then215            Assert.fail();216        } catch (MockitoException e) {217            Assert.assertEquals((("Mocks instantiated with constructor cannot be combined with " + (SerializableMode.ACROSS_CLASSLOADERS)) + " serialization mode."), e.getMessage());218        }219    }220    abstract static class AbstractThing {221        abstract String name();222        String fullName() {223            return "abstract " + (name());224        }225    }226    @Test227    public void abstract_method_returns_default() {228        CreatingMocksWithConstructorTest.AbstractThing thing = Mockito.spy(CreatingMocksWithConstructorTest.AbstractThing.class);229        Assert.assertEquals("abstract null", thing.fullName());230    }231    @Test232    public void abstract_method_stubbed() {233        CreatingMocksWithConstructorTest.AbstractThing thing = Mockito.spy(CreatingMocksWithConstructorTest.AbstractThing.class);234        Mockito.when(thing.name()).thenReturn("me");235        Assert.assertEquals("abstract me", thing.fullName());236    }237    @Test238    public void interface_method_stubbed() {239        List<?> list = Mockito.spy(List.class);240        Mockito.when(list.size()).thenReturn(12);241        Assert.assertEquals(12, list.size());242    }243    @Test244    public void calls_real_interface_method() {245        List list = Mockito.mock(List.class, Mockito.withSettings().defaultAnswer(Mockito.CALLS_REAL_METHODS));246        Assert.assertNull(list.get(1));247    }248    @Test249    public void handles_bridge_methods_correctly() {250        CreatingMocksWithConstructorTest.SomeConcreteClass<Integer> testBug = Mockito.spy(new CreatingMocksWithConstructorTest.SomeConcreteClass<Integer>());251        Assert.assertEquals("value", testBug.getValue(0));252    }253    public abstract class SomeAbstractClass<T> {254        protected abstract String getRealValue(T value);255        public String getValue(T value) {256            return getRealValue(value);257        }258    }259    public class SomeConcreteClass<T extends Number> extends CreatingMocksWithConstructorTest.SomeAbstractClass<T> {260        @Override261        protected String getRealValue(T value) {262            return "value";263        }264    }265    private static class AmbiguousWithPrimitive {266        public AmbiguousWithPrimitive(String s, int i) {267            data = s;268        }269        public AmbiguousWithPrimitive(Object o, int i) {270            data = "just an object";271        }272        private String data;273        public String getData() {274            return data;275        }276    }277    @Test278    public void can_spy_ambiguius_constructor_with_primitive() {279        CreatingMocksWithConstructorTest.AmbiguousWithPrimitive mock = Mockito.mock(CreatingMocksWithConstructorTest.AmbiguousWithPrimitive.class, Mockito.withSettings().useConstructor("String", 7).defaultAnswer(Mockito.CALLS_REAL_METHODS));280        Assert.assertEquals("String", mock.getData());281    }282}...

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