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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package org.graalvm.compiler.graph.test.matchers;

import org.hamcrest.Description;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeDiagnosingMatcher;
import org.hamcrest.core.IsNot;

import org.graalvm.compiler.graph.iterators.NodeIterable;

public class NodeIterableIsEmpty extends TypeSafeDiagnosingMatcher<NodeIterable<?>> {

    private static final NodeIterableIsEmpty INSTANCE = new NodeIterableIsEmpty();

    @Override
    public boolean matchesSafely(NodeIterable<?> iterable, Description mismatchDescription) {
        mismatchDescription.appendText("is a non-empty NodeIterable");
        return iterable.isEmpty();
    }

    @Override
    public void describeTo(Description description) {
        description.appendText("is an empty NodeIterable");
    }

    public static Matcher<NodeIterable<?>> isEmpty() {
        return INSTANCE;
    }

    public static Matcher<NodeIterable<?>> isNotEmpty() {
        return IsNot.not(INSTANCE);
    }
}