de.larssh.utils.test.Assertions Maven / Gradle / Ivy
// Generated by delombok at Thu Feb 27 09:09:15 CET 2020
package de.larssh.utils.test;
import static java.util.stream.Collectors.joining;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotEquals;
import java.util.Arrays;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.IntStream;
import org.jooq.lambda.function.Consumer3;
import org.joor.Reflect;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
/**
* This class contains helper methods for assertion.
*/
public final class Assertions {
/**
* Asserts that the methods {@link Object#equals(Object)} and
* {@link Object#hashCode()} of objects created by executing the {@code clazz}es
* constructor work as defined by {@code arguments}.
*
*
* The constructor of {@code clazz} is called multiple times using different
* combinations of arguments. The resulting objects equality is checked using
* declarations of {@code arguments}.
* {@link Reflects#create(Reflect, Object...)} is used to construct instances of
* {@code clazz}.
*
*
* {@code arguments} declares two kind of valid arguments for the class
* constructor and if changing the argument should change the objects equality.
*
*
* In addition to argument checks {@link Object#equals(Object)} is checked
* against {@code null}, {@code true} and the object itself while the first two
* are expected to differ from the object itself.
*
* @param clazz class to be instantiated based on given arguments
* @param arguments declaration of arguments and if changing arguments should
* change equality
*/
public static void assertEqualsAndHashCode(final Class clazz, final AssertEqualsAndHashCodeArguments arguments) {
final Reflect reflect = Reflect.onClass(clazz);
assertEqualsAndHashCode(a -> Reflects.create(reflect, a).get(), arguments);
}
/**
* Asserts that the methods {@link Object#equals(Object)} and
* {@link Object#hashCode()} of objects created by executing {@code constructor}
* work as defined by {@code arguments}.
*
*
* {@code constructor} is called multiple times using different combinations of
* arguments. The resulting objects equality is checked using declarations of
* {@code arguments}.
*
*
* {@code arguments} declares two kind of valid arguments for the constructor
* and if changing the argument should change the objects equality.
*
*
* In addition to argument checks {@link Object#equals(Object)} is checked
* against {@code null}, {@code true} and the object itself while the first two
* are expected to differ from the object itself.
*
* @param constructor function to construct object instances based on given
* arguments
* @param arguments declaration of arguments and if changing arguments should
* change equality
*/
@SuppressFBWarnings(value = "PRMC_POSSIBLY_REDUNDANT_METHOD_CALLS", justification = "need to call constructor twice to validate equals")
public static void assertEqualsAndHashCode(final Function constructor, final AssertEqualsAndHashCodeArguments arguments) {
final Function wrappedConstructor = wrapConstructorExceptions(constructor);
final Object object = wrappedConstructor.apply(arguments.getOriginal().toArray());
final int hashCode = object.hashCode();
assertNotEquals(null, object, "equals null");
assertNotEquals(Boolean.TRUE, object, "equals true");
assertEquals(object, object, "equals this");
final Object sameObject = wrappedConstructor.apply(arguments.getOriginal().toArray());
assertEquals(object, sameObject, "equals original arguments");
assertEquals(hashCode, sameObject.hashCode(), "hashCode original arguments");
IntStream.range(0, arguments.getOriginal().size()).forEach(index -> {
final Consumer3> consumer = arguments.isExpectEquality(index) ? org.junit.jupiter.api.Assertions::assertEquals : org.junit.jupiter.api.Assertions::assertNotEquals;
final Object newObject = wrappedConstructor.apply(arguments.getChangedArguments(index).toArray());
// Assert equals
final Supplier equalsMessage = () -> String.format("%sequals changed argument %d", arguments.isExpectEquality(index) ? "" : "not ", index + 1);
consumer.accept(object, newObject, equalsMessage);
// Assert hashCode
final Supplier hashCodeMessage = () -> String.format("hashCode changed argument %d", index + 1);
consumer.accept(hashCode, newObject.hashCode(), hashCodeMessage);
});
}
/**
* Wraps {@code constructor} to wrap exceptions thrown by that constructor with
* an {@link AssertionException} showing the used arguments.
*
* @param the constructors class
* @param constructor the constructor to wrap
* @return wrapped constructor
*/
@SuppressWarnings({"checkstyle:IllegalCatch", "PMD.AvoidCatchingGenericException"})
@SuppressFBWarnings(value = "EXS_EXCEPTION_SOFTENING_NO_CONSTRAINTS", justification = "throw AssertionException instead")
private static Function wrapConstructorExceptions(final Function constructor) {
return arguments -> {
try {
return constructor.apply(arguments);
} catch (final Exception e) {
throw new AssertionException(e, Arrays.stream(arguments).map(Object::toString).collect(joining("], [", "Failed constructing using [", "]")));
}
};
}
@java.lang.SuppressWarnings("all")
@edu.umd.cs.findbugs.annotations.SuppressFBWarnings(justification = "generated code")
@lombok.Generated
private Assertions() {
throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated");
}
}