Best junit code snippet using org.hamcrest.Interface Description.appendDescriptionOf
Source:ClassMatcherImpl.java  
...160    }161    @Override162    public ClassMatcher implementing(Matcher<Type> interfaceMatcher) {163//        this.matchers.addMatcher(164//                description -> description.appendText("should implement ").appendDescriptionOf(interfaceMatcher),165//                item -> Arrays.asList(item.getInterfaces()).stream().anyMatch(aClass -> interfaceMatcher.matches(aClass)),166//                (item, description) -> description.appendText("")167//        );168        this.matchers.addMatcher(169                description -> description.appendText("should implement ").appendDescriptionOf(interfaceMatcher),170                item -> {171                    for (Class anInterface : item.getInterfaces()) {172                        if(interfaceMatcher.matches(anInterface)) {173                            return true;174                        }175                    }176                    return false;177                },178                (item, description) -> description.appendDescriptionOf(interfaceMatcher)179        );180        return this;181    }182    @Override183    public ClassMatcher extending(Class aClass) {184        this.matchers.addMatcher(185                "extends " + aClass.getName(),186                item -> aClass.equals(item.getSuperclass()),187                (item, description) -> description.appendText("was false")188        );189        return this;190    }191}...Source:SomeNumberOfItems.java  
...30	}31	@Override32	public void describePredicateOnFinder(Finder<E, CollectionOf<E>, ?> finder,	Description description) {33		describeNumberExpectedTo(description);		34		description.appendDescriptionOf(finder);35	}36	@Override37	public boolean isSatisfiedBy(CollectionOf<E> foundElements) {38		return cardinalityConstraint.matches(foundElements.size());39	}40	41	@Override42	public void diagnoseNotSatisfyingTo(Description dissatisfactionDescription,43			CollectionOf<E> foundElements, Description notFoundDescription) {44		if(foundElements.size()>0)45			describeActualNumberFound(foundElements, dissatisfactionDescription);46		else{47			dissatisfactionDescription48				.appendText("Not found - ")49				.appendText(notFoundDescription.toString());50		}51	}52	53	protected void describeActualNumberFound(Collection<E> foundElements,54			Description failureDescription) {55		failureDescription.appendText("found ")56			.appendValue(foundElements.size())57			.appendText(" such elements")58			.appendDescriptionOf(describable(foundElements));59	}60	61	protected void describeNumberExpectedTo(Description description) {62		if(cardinalityConstraint instanceof CustomNumberMatcher)63			description64			.appendDescriptionOf(cardinalityConstraint)65			.appendText(" ");66		67		else68			description69			.appendText("there to be ")70			.appendDescriptionOf(cardinalityConstraint)71			.appendText(" of ");72	}73	74	public static  interface CustomNumberMatcher{}75	76	@Factory77	public static <E> Predicate<E, CollectionOf<E>> aNumberOfElements(Matcher<Integer> cardinalityConstraint){78		return new SomeNumberOfItems<E>(cardinalityConstraint);79	}80}...Source:TopologyMatchersImpl.java  
...46    @Override47    public void describeTo(Description description) {48      description49          .appendText(String.format("as interface of %s: ", _node))50          .appendDescriptionOf(_subMatcher);51    }52    @Override53    protected boolean matchesSafely(String item, Description mismatchDescription) {54      NodeInterfacePair pair = NodeInterfacePair.of(_node, item);55      if (!_subMatcher.matches(pair)) {56        mismatchDescription57            .appendText(String.format("%s as interface of %s did not satisfy: ", item, _node))58            .appendDescriptionOf(_subMatcher);59        return false;60      }61      return true;62    }63  }64  private TopologyMatchersImpl() {}65}...Source:Description.java  
1package org.hamcrest;2public interface Description {3    public static final Description NONE = new NullDescription();4    Description appendDescriptionOf(SelfDescribing selfDescribing);5    Description appendList(String str, String str2, String str3, Iterable<? extends SelfDescribing> iterable);6    Description appendText(String str);7    Description appendValue(Object obj);8    <T> Description appendValueList(String str, String str2, String str3, Iterable<T> iterable);9    <T> Description appendValueList(String str, String str2, String str3, T... tArr);10    public static final class NullDescription implements Description {11        @Override // org.hamcrest.Description12        public Description appendDescriptionOf(SelfDescribing value) {13            return this;14        }15        @Override // org.hamcrest.Description16        public Description appendList(String start, String separator, String end, Iterable<? extends SelfDescribing> iterable) {17            return this;18        }19        @Override // org.hamcrest.Description20        public Description appendText(String text) {21            return this;22        }23        @Override // org.hamcrest.Description24        public Description appendValue(Object value) {25            return this;26        }...appendDescriptionOf
Using AI Code Generation
1package com.example;2import org.hamcrest.Description;3import org.hamcrest.Factory;4import org.hamcrest.Matcher;5import org.hamcrest.TypeSafeMatcher;6public class IsInInclusiveRange<T extends Comparable<T>> extends TypeSafeMatcher<T> {7    private final T min;8    private final T max;9    public IsInInclusiveRange(T min, T max) {10        this.min = min;11        this.max = max;12    }13    public boolean matchesSafely(T item) {14        return min.compareTo(item) <= 0 && item.compareTo(max) <= 0;15    }16    public void describeTo(Description description) {17        description.appendText("a value between ").appendDescriptionOf(min).appendText(" and ").appendDescriptionOf(max);18    }19    public static <T extends Comparable<T>> Matcher<T> isInInclusiveRange(T min, T max) {20        return new IsInInclusiveRange<T>(min, max);21    }22}23package com.example;24import org.hamcrest.Matcher;25import org.junit.Test;26import java.math.BigDecimal;27import static com.example.IsInInclusiveRange.isInInclusiveRange;28import static org.hamcrest.MatcherAssert.assertThat;29import static org.hamcrest.Matchers.is;30public class IsInInclusiveRangeTest {31    public void testIsInInclusiveRange() {32        Matcher<BigDecimal> matcher = isInInclusiveRange(BigDecimal.ONE, BigDecimal.TEN);33        assertThat(BigDecimal.ONE, is(matcher));34        assertThat(BigDecimal.TEN, is(matcher));35        assertThat(BigDecimal.valueOf(5), is(matcher));36    }37}appendDescriptionOf
Using AI Code Generation
1import org.hamcrest.Description2import org.hamcrest.Matcher3import org.hamcrest.TypeSafeMatcher4class CustomDescriptionMatcher extends TypeSafeMatcher<String> {5    CustomDescriptionMatcher(Matcher<String> matcher, String description) {6    }7    boolean matchesSafely(String item) {8        matcher.matches(item)9    }10    void describeTo(Description description) {11        matcher.describeTo(description)12    }13    void describeMismatchSafely(String item, Description mismatchDescription) {14        matcher.describeMismatch(item, mismatchDescription)15    }16    void appendDescriptionOf(Description description) {17        description.appendText(this.description)18    }19}20def customDescriptionMatcher(Matcher<String> matcher, String description) {21    new CustomDescriptionMatcher(matcher, description)22}23assertThat("Hello World", customDescriptionMatcher(startsWith("Hello"), "Starts with Hello"))24	at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:20)25	at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:8)26	at Script1.run(Script1.groovy:52)appendDescriptionOf
Using AI Code Generation
1    public void describeTo(Description description) {2        description.appendText("a string containing ")3                .appendDescriptionOf(substringMatcher);4    }5}6public void testMatchesSafely() {7    String testString = "test string";8    assertThat(testString, containsString("test"));9}10public void testDoesNotMatchSafely() {11    String testString = "test string";12    assertThat(testString, not(containsString("test ")));13}14public void testDescribeMismatchSafely() {15    String testString = "test string";16    assertThrows(AssertionError.class,17            () -> assertThat(testString, containsString("test ")));18}19public void testDescribeTo() {20    String testString = "test string";21    assertThrows(AssertionError.class,22            () -> assertThat(testString, containsString("test ")));23}24public void testDescribeMismatchSafely() {25    String testString = "test string";26    assertThrows(AssertionError.class,27            () -> assertThat(testString, containsString("test ")));28}29public void testDescribeTo() {30    String testString = "test string";31    assertThrows(AssertionError.class,32            () -> assertThat(testString, containsString("test ")));33}34public void testDescribeMismatchSafely() {35    String testString = "test string";36    assertThrows(AssertionError.class,37            () -> assertThat(testString, containsString("test ")));38}39public void testDescribeTo() {40    String testString = "test string";41    assertThrows(AssertionError.class,42            () -> assertThat(testString, containsString("test ")));43}appendDescriptionOf
Using AI Code Generation
1import org.hamcrest.Description;2import org.hamcrest.Matcher;3import org.hamcrest.TypeSafeDiagnosingMatcher;4public class TypeSafeDiagnosingMatcherDemo extends TypeSafeDiagnosingMatcher<String>{5	public void describeTo(Description description) {6		description.appendText("a string with length of ");7		description.appendValue(10);8	}9	protected boolean matchesSafely(String item, Description mismatchDescription) {10		if(item.length() == 10){11			return true;12		}13		mismatchDescription.appendText("was a string with length of ");14		mismatchDescription.appendValue(item.length());15		return false;16	}17	public static Matcher<String> hasLengthOf10(){18		return new TypeSafeDiagnosingMatcherDemo();19	}20}21import static org.hamcrest.MatcherAssert.assertThat;22import static org.hamcrest.Matchers.equalTo;23import static org.hamcrest.Matchers.is;24import org.hamcrest.Matcher;25import org.junit.Test;26public class TypeSafeDiagnosingMatcherDemoTest {27	public void testHasLengthOf10(){28		Matcher<String> matcher = TypeSafeDiagnosingMatcherDemo.hasLengthOf10();29		assertThat("1234567890", is(matcher));30		assertThat("123456789", is(equalTo(matcher)));31	}32}appendDescriptionOf
Using AI Code Generation
1public class AppendingDescriptionOfMatcher<T> extends TypeSafeMatcher<T> {2    private final Matcher<T> matcher;3    private final T object;4    public AppendingDescriptionOfMatcher(Matcher<T> matcher, T object) {5        this.matcher = matcher;6        this.object = object;7    }8    public void describeTo(Description description) {9        matcher.describeTo(description);10        description.appendText(" ").appendDescriptionOf(object);11    }12    protected boolean matchesSafely(T item) {13        return matcher.matches(item);14    }15    protected void describeMismatchSafely(T item, Description mismatchDescription) {16        matcher.describeMismatch(item, mismatchDescription);17    }18    public static <T> Matcher<T> appendDescriptionOf(Matcher<T> matcher, T object) {19        return new AppendingDescriptionOfMatcher<>(matcher, object);20    }21}22public class AppendingDescriptionOfMatcher<T> extends TypeSafeMatcher<T> {23    private final Matcher<T> matcher;24    private final T object;25    public AppendingDescriptionOfMatcher(Matcher<T> matcher, T object) {26        this.matcher = matcher;27        this.object = object;28    }29    public void describeTo(Description description) {30        matcher.describeTo(description);31        description.appendText(" ").appendDescriptionOf(object);32    }33    protected boolean matchesSafely(T item) {34        return matcher.matches(item);35    }36    protected void describeMismatchSafely(T item, Description mismatchDescription) {37        matcher.describeMismatch(item, mismatchDescription);38    }39    public static <T> Matcher<T> appendDescriptionOf(Matcher<T> matcher, T object) {40        return new AppendingDescriptionOfMatcher<>(matcher, object);41    }42}appendDescriptionOf
Using AI Code Generation
1class StartsWith extends TypeSafeDiagnosingMatcher<String> {2    StartsWith(String prefix) {3    }4    protected boolean matchesSafely(String item, Description mismatchDescription) {5        boolean matches = item.startsWith(prefix)6        if (!matches) {7            mismatchDescription.appendText("was \"").appendText(item).appendText("\"")8        }9    }10    public void describeTo(Description description) {11        description.appendText("string starting with \"").appendText(prefix).appendText("\"")12    }13}14static Matcher<String> startsWith(String prefix) {15    return new StartsWith(prefix)16}17def "a string starting with a given prefix"() {18    "abc" == startsWith("a")19    "abc" != startsWith("b")20}21def "a string starting with a given prefix"() {22    "abc" == startsWith("a")23    "abc" != startsWith("b")24}25def "a string starting with a given prefix"() {26    "abc" == startsWith("a")27    "abc" != startsWith("b")28}29def "a string starting with a given prefix"() {30    "abc" == startsWith("a")31    "abc" != startsWith("b")32}33def "a string starting with a given prefix"() {34    "abc" == startsWith("a")35    "abc" != startsWith("b")36}37def "a string starting with a given prefix"() {38    "abc" == startsWith("a")39    "abc" != startsWith("b")40}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.
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