KotlinNotNullOperatorFilter.java

/*******************************************************************************
 * Copyright (c) 2009, 2019 Mountainminds GmbH & Co. KG and Contributors
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Evgeny Mandrikov - initial API and implementation
 *
 *******************************************************************************/
package org.jacoco.core.internal.analysis.filter;

import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.MethodNode;

/**
 * Filters branch in bytecode that Kotlin compiler generates for not-null
 * assertion operator.
 */
public final class KotlinNotNullOperatorFilter implements IFilter {

	public void filter(final MethodNode methodNode,
			final IFilterContext context, final IFilterOutput output) {
		final Matcher matcher = new Matcher();
		for (AbstractInsnNode i = methodNode.instructions
				.getFirst(); i != null; i = i.getNext()) {
			matcher.match(i, output);
		}
	}

	private static class Matcher extends AbstractMatcher {
		public void match(final AbstractInsnNode start,
				final IFilterOutput output) {
			if (Opcodes.IFNONNULL != start.getOpcode()) {
				return;
			}
			cursor = start;
			nextIsInvoke(Opcodes.INVOKESTATIC, "kotlin/jvm/internal/Intrinsics",
					"throwNpe", "()V");
			if (cursor == null) {
				return;
			}
			output.ignore(start, cursor);
		}
	}

}