Hamcrest matcher that matches a Lambda.

LambdaMatcher.java

package util.matcher;

import java.util.function.Function;

import org.hamcrest.BaseMatcher;
import org.hamcrest.Description;

public class LambdaMatcher<T> extends BaseMatcher<T> {
	private final Function<T, Boolean> matcher;
	private final String description;

	public LambdaMatcher(Function<T, Boolean> matcher,
						 String description) {
		this.matcher = matcher;
		this.description = description;
	}

	public LambdaMatcher(Function<T, Boolean> matcher) {
		this(matcher, "matches lambda");
	}

	public static <T> LambdaMatcher<T> matchesLambda(Function<T, Boolean> matcher) {
		return new LambdaMatcher<T>(matcher);
	}


	public static <T> LambdaMatcher<T> matchesLambda(Function<T, Boolean> matcher, String description) {
		return new LambdaMatcher<T>(matcher, description);
	}

	@Override
	public boolean matches(Object argument) {
		return matcher.apply((T) argument);
	}

	@Override
	public void describeTo(Description description) {
		description.appendText(this.description);
	}
}