How to use Annotation Type Theory class of org.junit.experimental.theories package

Best junit code snippet using org.junit.experimental.theories.Annotation Type Theory

Source:DataPoints.java

1package org.junit.experimental.theories;2import static java.lang.annotation.ElementType.FIELD;3import static java.lang.annotation.ElementType.METHOD;4import java.lang.annotation.Retention;5import java.lang.annotation.RetentionPolicy;6import java.lang.annotation.Target;7/**8 * Annotating an array or iterable-typed field or method with &#064;DataPoints9 * will cause the values in the array or iterable given to be used as potential10 * parameters for theories in that class when run with the11 * {@link org.junit.experimental.theories.Theories Theories} runner.12 * <p>13 * DataPoints will only be considered as potential values for parameters for14 * which their types are assignable. When multiple sets of DataPoints exist with15 * overlapping types more control can be obtained by naming the DataPoints using16 * the value of this annotation, e.g. with17 * <code>&#064;DataPoints({"dataset1", "dataset2"})</code>, and then specifying18 * which named set to consider as potential values for each parameter using the19 * {@link org.junit.experimental.theories.FromDataPoints &#064;FromDataPoints}20 * annotation.21 * <p>22 * Parameters with no specified source (i.e. without &#064;FromDataPoints or23 * other {@link org.junit.experimental.theories.ParametersSuppliedBy24 * &#064;ParameterSuppliedBy} annotations) will use all DataPoints that are25 * assignable to the parameter type as potential values, including named sets of26 * DataPoints.27 * <p>28 * DataPoints methods whose array types aren't assignable from the target29 * parameter type (and so can't possibly return relevant values) will not be30 * called when generating values for that parameter. Iterable-typed datapoints31 * methods must always be called though, as this information is not available32 * here after generic type erasure, so expensive methods returning iterable33 * datapoints are a bad idea.34 * 35 * <pre>36 * &#064;DataPoints37 * public static String[] dataPoints = new String[] { ... };38 * 39 * &#064;DataPoints40 * public static String[] generatedDataPoints() {41 *     return new String[] { ... };42 * }43 * 44 * &#064;Theory45 * public void theoryMethod(String param) {46 *     ...47 * }48 * </pre>49 * 50 * @see org.junit.experimental.theories.Theories51 * @see org.junit.experimental.theories.Theory52 * @see org.junit.experimental.theories.DataPoint53 * @see org.junit.experimental.theories.FromDataPoints54 */55@Retention(RetentionPolicy.RUNTIME)56@Target({ FIELD, METHOD })57public @interface DataPoints {58    String[] value() default {};59    Class<? extends Throwable>[] ignoredExceptions() default {};60}...

Source:DataPoint.java

1package org.junit.experimental.theories;2import static java.lang.annotation.ElementType.FIELD;3import static java.lang.annotation.ElementType.METHOD;4import java.lang.annotation.Retention;5import java.lang.annotation.RetentionPolicy;6import java.lang.annotation.Target;7/**8 * Annotating an field or method with &#064;DataPoint will cause the field value9 * or the value returned by the method to be used as a potential parameter for10 * theories in that class, when run with the11 * {@link org.junit.experimental.theories.Theories Theories} runner.12 * <p>13 * A DataPoint is only considered as a potential value for parameters for14 * which its type is assignable. When multiple {@code DataPoint}s exist 15 * with overlapping types more control can be obtained by naming each DataPoint 16 * using the value of this annotation, e.g. with17 * <code>&#064;DataPoint({"dataset1", "dataset2"})</code>, and then specifying18 * which named set to consider as potential values for each parameter using the19 * {@link org.junit.experimental.theories.FromDataPoints &#064;FromDataPoints}20 * annotation.21 * <p>22 * Parameters with no specified source (i.e. without &#064;FromDataPoints or23 * other {@link org.junit.experimental.theories.ParametersSuppliedBy24 * &#064;ParameterSuppliedBy} annotations) will use all {@code DataPoint}s that are25 * assignable to the parameter type as potential values, including named sets of26 * {@code DataPoint}s.27 * 28 * <pre>29 * &#064;DataPoint30 * public static String dataPoint = "value";31 * 32 * &#064;DataPoint("generated")33 * public static String generatedDataPoint() {34 *     return "generated value";35 * }36 * 37 * &#064;Theory38 * public void theoryMethod(String param) {39 *     ...40 * }41 * </pre>42 * 43 * @see org.junit.experimental.theories.Theories44 * @see org.junit.experimental.theories.Theory45 * @see org.junit.experimental.theories.DataPoint46 * @see org.junit.experimental.theories.FromDataPoints47 */48@Retention(RetentionPolicy.RUNTIME)49@Target({FIELD, METHOD})50public @interface DataPoint {51    String[] value() default {};52    Class<? extends Throwable>[] ignoredExceptions() default {};53}...

Source:FromDataPoints.java

1package org.junit.experimental.theories;2import java.lang.annotation.ElementType;3import java.lang.annotation.Retention;4import java.lang.annotation.RetentionPolicy;5import java.lang.annotation.Target;6import org.junit.experimental.theories.internal.SpecificDataPointsSupplier;7/**8 * Annotating a parameter of a {@link org.junit.experimental.theories.Theory9 * &#064;Theory} method with <code>&#064;FromDataPoints</code> will limit the10 * datapoints considered as potential values for that parameter to just the11 * {@link org.junit.experimental.theories.DataPoints DataPoints} with the given12 * name. DataPoint names can be given as the value parameter of the13 * &#064;DataPoints annotation.14 * <p>15 * DataPoints without names will not be considered as values for any parameters16 * annotated with &#064;FromDataPoints.17 * <pre>18 * &#064;DataPoints19 * public static String[] unnamed = new String[] { ... };20 * 21 * &#064;DataPoints("regexes")22 * public static String[] regexStrings = new String[] { ... };23 * 24 * &#064;DataPoints({"forMatching", "alphanumeric"})25 * public static String[] testStrings = new String[] { ... }; 26 * 27 * &#064;Theory28 * public void stringTheory(String param) {29 *     // This will be called with every value in 'regexStrings',30 *     // 'testStrings' and 'unnamed'.31 * }32 * 33 * &#064;Theory34 * public void regexTheory(&#064;FromDataPoints("regexes") String regex,35 *                         &#064;FromDataPoints("forMatching") String value) {36 *     // This will be called with only the values in 'regexStrings' as 37 *     // regex, only the values in 'testStrings' as value, and none 38 *     // of the values in 'unnamed'.39 * }40 * </pre>41 * 42 * @see org.junit.experimental.theories.Theory43 * @see org.junit.experimental.theories.DataPoint44 * @see org.junit.experimental.theories.DataPoints45 */46@Retention(RetentionPolicy.RUNTIME)47@Target(ElementType.PARAMETER)48@ParametersSuppliedBy(SpecificDataPointsSupplier.class)49public @interface FromDataPoints {50    String value();51}...

Source:ParametersSuppliedBy.java

1package org.junit.experimental.theories;2import static java.lang.annotation.ElementType.ANNOTATION_TYPE;3import static java.lang.annotation.ElementType.PARAMETER;4import java.lang.annotation.Retention;5import java.lang.annotation.RetentionPolicy;6import java.lang.annotation.Target;7/**8 * Annotating a {@link org.junit.experimental.theories.Theory Theory} method9 * parameter with &#064;ParametersSuppliedBy causes it to be supplied with10 * values from the named11 * {@link org.junit.experimental.theories.ParameterSupplier ParameterSupplier}12 * when run as a theory by the {@link org.junit.experimental.theories.Theories13 * Theories} runner.14 * 15 * In addition, annotations themselves can be annotated with16 * &#064;ParametersSuppliedBy, and then used similarly. ParameterSuppliedBy17 * annotations on parameters are detected by searching up this heirarchy such18 * that these act as syntactic sugar, making:19 * 20 * <pre>21 * &#064;ParametersSuppliedBy(Supplier.class)22 * public &#064;interface SpecialParameter { }23 * 24 * &#064;Theory25 * public void theoryMethod(&#064;SpecialParameter String param) {26 *   ...27 * }28 * </pre>29 * 30 * equivalent to:31 * 32 * <pre>33 * &#064;Theory34 * public void theoryMethod(&#064;ParametersSuppliedBy(Supplier.class) String param) {35 *   ...36 * }37 * </pre>38 */39@Retention(RetentionPolicy.RUNTIME)40@Target({ ANNOTATION_TYPE, PARAMETER })41public @interface ParametersSuppliedBy {42    Class<? extends ParameterSupplier> value();43}...

Annotation Type Theory

Using AI Code Generation

1public class TestClass {2    public void testMethod(@FromDataPoints("data") int x, @FromDataPoints("data") int y) {3        assertThat(x + y, is(4));4    }5    @DataPoints("data")6    public static int[] data() {7        return new int[]{1, 3};8    }9}10@RunWith(JUnitParamsRunner.class)11public class JUnitParamsTest {12    @Parameters({"1, 3", "2, 2", "3, 1"})13    public void testMethod(int x, int y) {14        assertThat(x + y, is(4));15    }16}17@RunWith(JUnitParamsRunner.class)18public class JUnitParamsTest {19    @Parameters(method = "data")20    public void testMethod(int x, int y) {21        assertThat(x + y, is(4));22    }23    private Object[] data() {24        return new Object[]{25                new Object[]{1, 3},26                new Object[]{2, 2},27                new Object[]{3, 1}28        };29    }30}31@RunWith(JUnitParamsRunner.class)32public class JUnitParamsTest {33    @Parameters(source = DataProvider.class)34    public void testMethod(int x, int y) {35        assertThat(x + y, is(4));36    }37    public static class DataProvider {38        public static Object[] data() {39            return new Object[]{40                    new Object[]{1, 3},41                    new Object[]{2, 2},42                    new Object[]{3, 1}43            };44        }45    }46}47@RunWith(JUnitParamsRunner.class)48public class JUnitParamsTest {49    public void testMethod(int x, int y) {50        assertThat(x + y, is(4));51    }52    private Object parametersForTestMethod() {53        return new Object[]{54                new Object[]{1, 3},55                new Object[]{2, 2},56                new Object[]{3, 1}57        };58    }59}60@RunWith(JUnitParams

Annotation Type Theory

Using AI Code Generation

1import org.junit.experimental.theories.*;2import org.junit.runner.*;3import static org.junit.Assert.*;4import java.util.*;5@RunWith(Theories.class)6public class TheoriesTest {7    @DataPoint public static int INT_1 = 1;8    @DataPoint public static int INT_2 = 2;9    @DataPoint public static int INT_3 = 3;10    @DataPoint public static int INT_4 = 4;11    @DataPoint public static int INT_5 = 5;12    @DataPoint public static int INT_6 = 6;13    @DataPoint public static int INT_7 = 7;14    @DataPoint public static int INT_8 = 8;15    @DataPoint public static int INT_9 = 9;16    @DataPoint public static int INT_10 = 10;17    @DataPoint public static int INT_11 = 11;18    @DataPoint public static int INT_12 = 12;19    @DataPoint public static int INT_13 = 13;20    @DataPoint public static int INT_14 = 14;21    @DataPoint public static int INT_15 = 15;22    @DataPoint public static int INT_16 = 16;23    @DataPoint public static int INT_17 = 17;24    @DataPoint public static int INT_18 = 18;25    @DataPoint public static int INT_19 = 19;26    @DataPoint public static int INT_20 = 20;27    @DataPoint public static int INT_21 = 21;28    @DataPoint public static int INT_22 = 22;29    @DataPoint public static int INT_23 = 23;30    @DataPoint public static int INT_24 = 24;31    @DataPoint public static int INT_25 = 25;32    @DataPoint public static int INT_26 = 26;33    @DataPoint public static int INT_27 = 27;34    @DataPoint public static int INT_28 = 28;35    @DataPoint public static int INT_29 = 29;36    @DataPoint public static int INT_30 = 30;37    @DataPoint public static int INT_31 = 31;38    @DataPoint public static int INT_32 = 32;

Annotation Type Theory

Using AI Code Generation

1@RunWith(Theories.class)2public class TheoryTest {3	public static int INT_PARAM_1 = 1;4	public static int INT_PARAM_2 = 2;5	public static int INT_PARAM_3 = 3;6	public static int[] INT_PARAMS = {1, 2, 3};7	public static String STRING_PARAM_1 = "1";8	public static String STRING_PARAM_2 = "2";9	public static String STRING_PARAM_3 = "3";10	public static String[] STRING_PARAMS = {"1", "2", "3"};11	public void testTheory(int intParam, String stringParam) {12		System.out.println("intParam: " + intParam + ", stringParam: " + stringParam);13	}14}

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