How to use describeMismatch method of org.hamcrest.Interface Matcher class

Best junit code snippet using org.hamcrest.Interface Matcher.describeMismatch

Source:MatcherGenericTypeExtractorTest.java

...46    private class IntMatcherFromInterface extends BaseMatcher<Integer> {47        public boolean matches(Object o) {48            return true;49        }50        public void describeMismatch(Object item, Description mismatchDescription) {}51        public void describeTo(Description description) {}52    }53    //Static Matcher interface implementation (instead of the BaseMatcher)54    private static class StaticIntMatcherFromInterface extends BaseMatcher<Integer> {55        public boolean matches(Object o) {56            return true;57        }58        public void describeMismatch(Object item, Description mismatchDescription) {}59        public void describeTo(Description description) {}60    }61    //non-generic matcher implementing the interface62    @SuppressWarnings("rawtypes")63    private static class NonGenericMatcherFromInterface extends BaseMatcher {64        public boolean matches(Object o) {65            return true;66        }67        public void describeMismatch(Object item, Description mismatchDescription) {}68        public void describeTo(Description description) {}69    }70    private interface IMatcher extends Matcher<Integer> {}71    //non-generic matcher implementing the interface72    private static class SubclassGenericMatcherFromInterface extends BaseMatcher<Integer> implements Serializable, Cloneable, IMatcher {73        public boolean matches(Object o) {74            return true;75        }76        public void describeMismatch(Object item, Description mismatchDescription) {}77        public void describeTo(Description description) {}78    }79    //I refuse to comment on the sanity of this case80    private static class InsaneEdgeCase extends SubclassGenericMatcherFromInterface {}81    @Test82    public void findsGenericType() {83        assertEquals(Integer.class, genericTypeOfMatcher(IntMatcher.class));84        assertEquals(Integer.class, genericTypeOfMatcher(StaticIntMatcher.class));85        assertEquals(Integer.class, genericTypeOfMatcher(IntMatcherFromInterface.class));86        assertEquals(Integer.class, genericTypeOfMatcher(StaticIntMatcherSubclass.class));87        assertEquals(Integer.class, genericTypeOfMatcher(IntMatcherFromInterface.class));88        assertEquals(Integer.class, genericTypeOfMatcher(StaticIntMatcherFromInterface.class));89        assertEquals(Integer.class, genericTypeOfMatcher(SubclassGenericMatcherFromInterface.class));90        assertEquals(Integer.class, genericTypeOfMatcher(InsaneEdgeCase.class));91        assertEquals(Integer.class, genericTypeOfMatcher(new BaseMatcher<Integer>() {92            public void describeTo(Description description) {93            }94            public boolean matches(Object o) {95                return false;96            }97        }.getClass()));98        assertEquals(Integer.class, genericTypeOfMatcher(new BaseMatcher<Integer>() {99            public void describeTo(Description description) {100            }101            public boolean matches(Object o) {102                return false;103            }104            public void describeMismatch(Object item, Description mismatchDescription) {105            }106        }.getClass()));107        assertEquals(Object.class, genericTypeOfMatcher(Object.class));108        assertEquals(Object.class, genericTypeOfMatcher(String.class));109        assertEquals(Object.class, genericTypeOfMatcher(HashMap.class));110        assertEquals(Object.class, genericTypeOfMatcher(new HashMap<String, String>() {111        }.getClass()));112        assertEquals(Object.class, genericTypeOfMatcher(NonGenericMatcher.class));113        assertEquals(Object.class, genericTypeOfMatcher(NonGenericMatcherFromInterface.class));114    }115}...

Source:QuickMatcherBase.java

...16 * <pre>{@code 17 *   if (matches(item)) {18 *       return true;19 *   } else {20 *       describeMismatch(item, description);21 *       return false;22 *   }23 * }</pre>24 * <p>25 * If you want to override {@link #matches(java.lang.Object, org.hamcrest.Description)},26 * extend {@link QuickDiagnosingMatcherBase} instead.27 * @param <T>28 */29public abstract class QuickMatcherBase<T> 30                extends BaseMatcher<T> 31                implements QuickDiagnosingMatcher<T> {3233    /** {@inheritDoc} */34    @Override35    public abstract boolean matches(Object item);3637    /** {@inheritDoc} */38    @Override39    public abstract void describeMismatch(Object item, Description description);4041    /**42     * <pre>{@code 43     *   if (matches(item)) {44     *       return true;45     *   } else {46     *       describeMismatch(item, description);47     *       return false;48     *   }49     * }</pre>50     * @param item51     * @param mismatch52     * @return match 53     */54    @Override55    public final boolean matches(Object item, Description mismatch) {56        if (matches(item)) {57            return true;58        } else {59            describeMismatch(item, mismatch);60            return false;61        }62    }6364    @Override65    public <I> MatchResult<I> matchResult(I item) {66        StringDescription mismatch = new StringDescription();67        if (matches(item, mismatch)) {68            return new MatchResultSuccess<>(item, this);69        } else {70            return new MatchResultMismatch<>(item, this, mismatch.toString());71        }72    }73}
...

Source:MatcherTestUtils.java

...18    matcher.describeTo(description);19    return description.toString();20  }21  /**22   * Shorthand function to calling {@link Matcher#describeMismatch(Object, Description)} and getting23   * the String representation of that description.24   *25   * @param matcher The matcher which we want the mismatch description for.26   * @param actual The actual value that triggered the mismatch.27   * @return The string set by {@link Matcher#describeMismatch(Object, Description)}.28   */29  public static String getMismatchDescription(Matcher<?> matcher, Object actual) {30    Description description = new StringDescription();31    matcher.describeMismatch(actual, description);32    return description.toString();33  }34  /** Object transformer used for various overloads of the {@code join} method. */35  interface Transformer<F, T> {36    T transform(F original);37  }38  /**39   * Similar implementation to {@link android.text.TextUtils#join(CharSequence, Object[])} but40   * allows for object transformations on each element.41   */42  public static <T> String join(CharSequence delimiter, T[] tokens, Transformer<T, ?> transformer) {43    StringBuilder sb = new StringBuilder();44    for (int i = 0; i < tokens.length; ++i) {45      if (i != 0) {...

Source:DescribingMatcher.java

...15    //---------------------------------------------------------------------16    // Static definitions, members, initialization and constructors17    //---------------------------------------------------------------------18    private DescribeTo describeTo;19    private DescribeMismatch describeMismatch;20    DescribingMatcher()21    {22        super();23    }24    //endregion25    @Override26    public final void describeTo( Description description )27    {28        describeTo.describeTo( description );29    }30    @Override31    protected final void describeMismatchSafely( T item, Description mismatchDescription )32    {33        describeMismatch.describeMismatch( mismatchDescription );34    }35    protected final void assignDescribers( DescribingMatcher.DescribeTo describeTo,36                                           DescribingMatcher.DescribeMismatch describeMismatch )37    {38        this.describeTo = describeTo;39        this.describeMismatch = describeMismatch;40    }41    protected interface DescribeTo42    {43        void describeTo( Description description );44    }45    protected interface DescribeMismatch46    {47        void describeMismatch( Description description );48    }49}...

describeMismatch

Using AI Code Generation

1import org.hamcrest.Description;2import org.hamcrest.Matcher;3import org.hamcrest.TypeSafeMatcher;4public class MyMatcher extends TypeSafeMatcher<String> {5    public void describeTo(Description description) {6        description.appendText("MyMatcher");7    }8    protected boolean matchesSafely(String item) {9        return true;10    }11    protected void describeMismatchSafely(String item, Description mismatchDescription) {12        mismatchDescription.appendText("MyMatcher mismatch");13    }14}15public class MyMatcherTest {16    public void testMyMatcher() {17        Matcher<String> myMatcher = new MyMatcher();18        assertThat("test", myMatcher);19    }20}21import static org.hamcrest.CoreMatchers.*;22import static org.hamcrest.MatcherAssert.assertThat;23public class MyMatcherTest {24    public void testMyMatcher() {25        Matcher<String> myMatcher = (s) -> s.length() > 3;26        assertThat("test", myMatcher);27    }28}29import static org.hamcrest.CoreMatchers.*;30import static org.hamcrest.MatcherAssert.assertThat;31public class MyMatcherTest {32    public void testMyMatcher() {33        Matcher<String> myMatcher = equalTo("test");34        assertThat("test", myMatcher);35    }36}37import static org.hamcrest.CoreMatchers.*;38import static org.hamcrest.MatcherAssert.assertThat;39public class MyMatcherTest {

describeMismatch

Using AI Code Generation

1Matcher<T> {2    public void describeMismatch(Object item, Description mismatchDescription) {3        mismatchDescription.appendText("was ").appendValue(item);4    }5}6    public void describeMismatchSafely(T item, Description mismatchDescription) {7        mismatchDescription.appendText("was ").appendValue(item);8    }9}10    public void describeMismatchSafely(T item, Description mismatchDescription) {11        mismatchDescription.appendText("was ").appendValue(item);12    }13}14    public void describeMismatchSafely(T item, Description mismatchDescription) {15        mismatchDescription.appendText("was ").appendValue(item);16    }17}18    public void describeMismatchSafely(T item, Description mismatchDescription) {19        mismatchDescription.appendText("was ").appendValue(item);20    }21}22    public void describeMismatchSafely(T item, Description mismatchDescription) {23        mismatchDescription.appendText("was ").appendValue(item);24    }25}26    public void describeMismatchSafely(T item, Description mismatchDescription) {27        mismatchDescription.appendText("was ").appendValue(item);28    }29}30    public void describeMismatchSafely(T item, Description mismatchDescription) {31        mismatchDescription.appendText("was ").appendValue(item);32    }33}

describeMismatch

Using AI Code Generation

1import org.hamcrest.Description;2import org.hamcrest.Matcher;3import org.hamcrest.TypeSafeDiagnosingMatcher;4public class IsIn<T> extends TypeSafeDiagnosingMatcher<Iterable<? super T>> {5    private final Matcher<? super T> elementMatcher;6    public static <T> Matcher<Iterable<? super T>> isIn(Matcher<? super T> elementMatcher) {7        return new IsIn<T>(elementMatcher);8    }9    public IsIn(Matcher<? super T> elementMatcher) {10        this.elementMatcher = elementMatcher;11    }12    public void describeTo(Description description) {13        description.appendText("an iterable containing ").appendDescriptionOf(elementMatcher);14    }15    protected boolean matchesSafely(Iterable<? super T> item, Description mismatchDescription) {16        for (Object actualElement : item) {17            if (elementMatcher.matches(actualElement)) {18                return true;19            }20        }21        mismatchDescription.appendText("no item in iterable ");22        elementMatcher.describeMismatch(item, mismatchDescription);23        return false;24    }25}26import static org.hamcrest.MatcherAssert.assertThat;27import static org.hamcrest

describeMismatch

Using AI Code Generation

1import org.hamcrest.Matcher2import org.hamcrest.StringDescription3import org.hamcrest.core.IsEqual4import org.hamcrest.core.IsNot5def matcher = new IsEqual(expectedValue)6def mismatchDescription = new StringDescription()7matcher.describeMismatch(actualValue, mismatchDescription)8println mismatchDescription.toString()9def matcher = new IsNot(expectedValue)10def mismatchDescription = new StringDescription()11matcher.describeMismatch(actualValue, mismatchDescription)12println mismatchDescription.toString()13import org.hamcrest.Matcher14import org.hamcrest.StringDescription15import org.hamcrest.core.IsEqual16import org.hamcrest.core.IsNot17def matcher = new IsEqual(expectedValue)18def mismatchDescription = new StringDescription()19matcher.describeMismatch(actualValue, mismatchDescription)20println mismatchDescription.toString()21def matcher = new IsNot(expectedValue)22def mismatchDescription = new StringDescription()23matcher.describeMismatch(actualValue, mismatchDescription)24println mismatchDescription.toString()25import org.hamcrest.Matcher26import org.hamcrest.StringDescription27import org.hamcrest.core.IsEqual28import org.hamcrest.core.IsNot29def matcher = new IsEqual(expectedValue)30def mismatchDescription = new StringDescription()31matcher.describeMismatch(actualValue, mismatchDescription)32println mismatchDescription.toString()33def matcher = new IsNot(expectedValue)34def mismatchDescription = new StringDescription()35matcher.describeMismatch(actualValue, mismatchDescription)36println mismatchDescription.toString()37import org.hamcrest.Matcher38import org.hamcrest.StringDescription39import org.hamcrest.core.IsEqual40import org.hamcrest.core.IsNot41def matcher = new IsEqual(expectedValue)42def mismatchDescription = new StringDescription()43matcher.describeMismatch(actualValue, mismatchDescription)

JUnit Tutorial:

LambdaTest also has a detailed JUnit tutorial explaining its features, importance, advanced use cases, best practices, and more to help you get started with running your automation testing scripts.

JUnit Tutorial Chapters:

Here are the detailed JUnit testing chapters to help you get started:

Importance of Unit testing - Learn why Unit testing is essential during the development phase to identify bugs and errors.
Top Java Unit testing frameworks - Here are the upcoming JUnit automation testing frameworks that you can use in 2023 to boost your unit testing.
What is the JUnit framework
Why is JUnit testing important - Learn the importance and numerous benefits of using the JUnit testing framework.
Features of JUnit - Learn about the numerous features of JUnit and why developers prefer it.
JUnit 5 vs. JUnit 4: Differences - Here is a complete comparison between JUnit 5 and JUnit 4 testing frameworks.
Setting up the JUnit environment - Learn how to set up your JUnit testing environment.
Getting started with JUnit testing - After successfully setting up your JUnit environment, this chapter will help you get started with JUnit testing in no time.
Parallel testing with JUnit - Parallel Testing can be used to reduce test execution time and improve test efficiency. Learn how to perform parallel testing with JUnit.
Annotations in JUnit - When writing automation scripts with JUnit, we can use JUnit annotations to specify the type of methods in our test code. This helps us identify those methods when we run JUnit tests using Selenium WebDriver. Learn in detail what annotations are in JUnit.
Assertions in JUnit - Assertions are used to validate or test that the result of an action/functionality is the same as expected. Learn in detail what assertions are and how to use them while performing JUnit testing.
Parameterization in JUnit - Parameterized Test enables you to run the same automated test scripts with different variables. By collecting data on each method's test parameters, you can minimize time spent on writing tests. Learn how to use parameterization in JUnit.
Nested Tests In JUnit 5 - A nested class is a non-static class contained within another class in a hierarchical structure. It can share the state and setup of the outer class. Learn about nested annotations in JUnit 5 with examples.
Best practices for JUnit testing - Learn about the best practices, such as always testing key methods and classes, integrating JUnit tests with your build, and more to get the best possible results.
Advanced Use Cases for JUnit testing - Take a deep dive into the advanced use cases, such as how to run JUnit tests in Jupiter, how to use JUnit 5 Mockito for Unit testing, and more for JUnit testing.