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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)

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