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How to use describeTo method of org.hamcrest.CustomMatcher class

Best junit code snippet using org.hamcrest.CustomMatcher.describeTo

Source:JavaMatchers.java

...32            Invariants.assertNotNull(descriptionOfWhatIsWanted);33            this.fixedDescription = "expected " + descriptionOfWhatIsWanted;34        }35        @Override36        public void describeTo(Description description) {37            description.appendText(fixedDescription);38        }39        @Override40        public abstract boolean matches(Object arg0);41    }42    /**43     * Checks if object has proper toString defined. This matcher can be44     * replaced with JUnit 4.845     */46    public static Matcher<Object> hasToString() {47        return new TypeSafeMatcher<Object>() {48            @Override49            public boolean matchesSafely(Object objectToTest) {50                try {51                    objectToTest.getClass().getDeclaredMethod("toString");52                } catch (Exception e) {53                    return false;54                }55                String s = objectToTest.toString();56                if (s == null || s.length() == 0) {57                    return false;58                }59                return true;60            }61            @Override62            public void describeTo(Description description) {63                description.appendText("proper toString()");64            }65        };66    }67    /**68     * Checks if array is non-empty. This matcher can be replaced with JUnit 4.869     */70    public static Matcher<Object[]> hasItemInArray() {71        return new TypeSafeMatcher<Object[]>() {72            @Override73            public boolean matchesSafely(Object[] arrayToTest) {74                if (arrayToTest == null || arrayToTest.length == 0) {75                    return false;76                }77                return true;78            }79            @Override80            public void describeTo(Description description) {81                description.appendText("non-empty array");82            }83        };84    }85    /**86     * Checks if list is non-empty. This matcher can be replaced with JUnit 4.887     */88    public static Matcher<Collection<?>> hasItems() {89        return new TypeSafeMatcher<Collection<?>>() {90            @Override91            public boolean matchesSafely(Collection<?> collection) {92                if (collection == null || collection.isEmpty()) {93                    return false;94                }95                return true;96            }97            @Override98            public void describeTo(Description description) {99                description.appendText("non-empty list");100            }101        };102    }103    /**104     * Checks if collection has the given number of items.105     */106    public static Matcher<Collection<?>> hasItems(final int numberOfItems) {107        return new TypeSafeMatcher<Collection<?>>() {108            @Override109            public boolean matchesSafely(Collection<?> collection) {110                if (collection == null || collection.size() != numberOfItems) {111                    return false;112                }113                return true;114            }115            @Override116            public void describeTo(Description description) {117                description.appendText("expected a collection with "118                        + numberOfItems + " items");119            }120        };121    }122    /**123     * Checks if the collection is empty124     */125    public static Matcher<Collection<?>> hasNoItems() {126        return hasItems(0);127    }128    /**129     * Checks if the collection has exactly one item130     */131    public static Matcher<Collection<?>> hasOneItem() {132        return hasItems(1);133    }134    /**135     * Checks if the object is serializable136     */137    public static Matcher<Object> isSerializable() {138        return new BaseMatcher<Object>() {139            @Override140            public boolean matches(Object instance) {141                return Serialization.isSerializable(instance);142            }143            @Override144            public void describeTo(Description description) {145                description.appendText("serializable object");146            }147        };148    }149    /**150     * Checks if value is null. Shortcut for is(nullValue()).151     */152    public static Matcher<Object> isNullValue() {153        return is(nullValue());154    }155}...

Source:ExceptionMatcher.java

...44  private ExceptionMatcher(Matcher<? super Class<? extends Throwable>> typeMatcher) {45    this.typeMatcher = requireNonNull(typeMatcher);46  }47  @Override48  public void describeTo(Description description) {49    typeMatcher.describeTo(description);50    if (messageMatcher != ANY_MESSAGE) {51      description.appendText(" with message ");52      messageMatcher.describeTo(description);53    }54    if (causeMatcher != ANY_CAUSE) {55      description.appendText(" with cause ");56      causeMatcher.describeTo(description);57    }58  }59  @Override60  protected boolean matchesSafely(Closure item) {61    try {62      item.run();63      return false;64    } catch (Throwable e) {65      if (debug) {66        e.printStackTrace();67      }68      failure = e;69      boolean match = typeMatcher.matches(e) && messageMatcher.matches(e.getMessage()) && causeMatcher.matches(e.getCause());70      if (!match) {...

Source:TestMatchers.java

...29    }30    public static Matcher<Throwable> throwableWithMessage(Matcher<String> messageMatcher) {31        return new BaseMatcher<Throwable>() {32            @Override33            public void describeTo(Description description) {34                description.appendText("a throwable with message of ").appendDescriptionOf(messageMatcher);35            }36            @Override37            public boolean matches(Object actual) {38                if (actual instanceof Throwable) {39                    final Throwable throwable = (Throwable) actual;40                    return messageMatcher.matches(throwable.getMessage());41                } else {42                    return false;43                }44            }45            @Override46            public void describeMismatch(Object item, Description description) {47                super.describeMismatch(item, description);...

Source:CustomMatcher.java

...33                    throw new ClassCastException(error);34                }35            }36            @Override37            public void describeTo(Description description) {38                description.appendText("Custom matching result ");39                matcher.describeTo(description);40            }41        };42    }43    private static Class getGenericClass(Object object) {44        Class<?> clazz = object.getClass();45        Type[] type = clazz.getGenericInterfaces();46        // ClassCastException is occur when no generic type is specified on MatcherRule like this47        // expect(id(android.R.id.message)).should(new CustomMatcher.MatcherRule() {48        //     @Override49        //     public boolean matches(View view) {50        //        return false;51        //    }});52        try {53            ParameterizedType pt = (ParameterizedType) type[0];...

Source:AssertThatTest.java

...49        protected boolean matchesSafely(String item) {50            return expected.equals(item);51        }52        @Override53        public void describeTo(Description description) {54            description.appendValue(expected);55        }56    }57}...

Source:HamcrestSUT.java

...38            HamcrestSUT incoming = (HamcrestSUT) item;39            return incoming.getName().equals(name) && incoming.getId() == id;40        }41        @Override42        public void describeTo(Description description) {43        }44    }45}...

describeTo

Using AI Code Generation

1import org.hamcrest.CustomMatcher2import org.hamcrest.Matcher3import org.hamcrest.MatcherAssert4import org.hamcrest.Matchers5import org.junit.Test6class CustomMatcherTest {7    fun testDescribeTo() {8        val matcher = CustomMatcher<String>("custom matcher") {9            it.startsWith("a")10        }11        MatcherAssert.assertThat("abc", matcher)12        MatcherAssert.assertThat("bcd", Matchers.not(matcher))13    }14}15	at org.hamcrest.CustomMatcher.describeTo(CustomMatcher.java:59)16	at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:20)17	at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:8)18	at CustomMatcherTest.testDescribeTo(CustomMatcherTest.kt:17)19	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)20	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)21	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)22	at java.lang.reflect.Method.invoke(Method.java:498)23	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)24	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)25	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)26	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)27	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)28	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)29	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)30	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)31	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)32	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)33	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)34	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)35	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)36	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)37	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(J

describeTo

Using AI Code Generation

1import org.hamcrest.CustomMatcher2import org.hamcrest.Matcher3class IsEven extends CustomMatcher<Integer> {4    IsEven() {5        super("an even number")6    }7    boolean matches(Object item) {8    }9}10assertThat 2, new IsEven()11import org.hamcrest.BaseMatcher12import org.hamcrest.Description13import org.hamcrest.Matcher14class IsEven extends BaseMatcher<Integer> {15    boolean matches(Object item) {16    }17    void describeTo(Description description) {18        description.appendText("an even number")19    }20}21assertThat 2, new IsEven()22import org.hamcrest.TypeSafeMatcher23import org.hamcrest.Matcher24class IsEven extends TypeSafeMatcher<Integer> {25    boolean matchesSafely(Integer item) {26    }27    void describeTo(Description description) {28        description.appendText("an even number")29    }30}31assertThat 2, new IsEven()32import org.hamcrest.Description33import org.hamcrest.Matcher34class IsEven implements Matcher<Integer> {35    boolean matches(Object item) {36    }37    void describeTo(Description description) {38        description.appendText("an even number")39    }40}41assertThat 2, new IsEven()42import org.hamcrest.StringDescription43import org.hamcrest.Matcher44class IsEven implements Matcher<Integer> {45    boolean matches(Object item) {46    }47    void describeTo(Description description) {48        description.appendText("an even number")49    }50}51assertThat 2, new IsEven()52import org.hamcrest.BaseMatcher53import org.hamcrest.Description54import org.hamcrest.Matcher55class IsEven extends BaseMatcher<Integer> {

describeTo

Using AI Code Generation

1import org.hamcrest.CustomMatcher;2import org.junit.Test;3public class CustomMatcherTest {4    public void testCustomMatcher() {5        CustomMatcher<Integer> customMatcher = new CustomMatcher<Integer>("custom matcher") {6            public boolean matchesSafely(Integer item) {7                return item > 5;8            }9        };10        assertThat(10, customMatcher);11        assertThat(5, not(customMatcher));12    }13}

describeTo

Using AI Code Generation

1def matcher = new CustomMatcher("some description") {2    boolean matches(Object item) {3    }4}5assert matcher.describeTo("some description")6def matcher = new CustomMatcher("some description") {7    boolean matches(Object item) {8    }9}10assert matcher.describeMismatch("actual value", "actual value")11def matcher = new CustomMatcher("some description") {12    boolean matchesSafely(Object item) {13    }14}15assert matcher.describeMismatchSafely("actual value", "actual value")16def matcher = new CustomMatcher("some description") {17    boolean matchesSafely(Object item) {18    }19}20assert matcher.matchesSafely("actual value")21def description = new Description() {22    void appendText(String text) {23    }24}25assert description.appendText("some text")26def description = new Description() {27    void appendValue(Object value) {28    }29}30assert description.appendValue("some value")31def description = new Description() {32    void appendValueList(String start, String separator, String end, Object... values) {33    }34}35assert description.appendValueList("start", "separator", "end", "value1", "value2")36def description = new Description() {37    void appendValueList(String start, String separator, String end, Iterable<?> values) {38    }39}40assert description.appendValueList("start", "separator", "end", ["value1", "value2"])41def description = new Description() {42    void appendList(String start, String separator, String end, Iterable<?> values) {

describeTo

Using AI Code Generation

1import org.hamcrest.BaseMatcher;2import org.hamcrest.Description;3import org.hamcrest.Matcher;4public class CustomMatcher<T> extends BaseMatcher<T> {5    private final Matcher<T> matcher;6    private final String description;7    public CustomMatcher(Matcher<T> matcher, String description) {8        this.matcher = matcher;9        this.description = description;10    }11    public boolean matches(Object item) {12        return matcher.matches(item);13    }14    public void describeTo(Description description) {15        description.appendText(this.description);16    }17}18import org.hamcrest.BaseMatcher;19import org.hamcrest.Description;20import org.hamcrest.Matcher;21public class CustomMatcher<T> extends BaseMatcher<T> {22    private final Matcher<T> matcher;23    private final String description;24    public CustomMatcher(Matcher<T> matcher, String description) {25        this.matcher = matcher;26        this.description = description;27    }28    public boolean matches(Object item) {29        return matcher.matches(item);30    }31    public void describeTo(Description description) {32        description.appendText(this.description);33    }34}

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