Add filter for Kotlin default methods (#1012)

2 files changed, 47 insertions, 1 deletions

diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/Filters.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/Filters.java
index bbe041f6..b25bcf5c 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/Filters.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/Filters.java
@@ -46,7 +46,7 @@ public final class Filters implements IFilter {
 				new KotlinUnsafeCastOperatorFilter(),
 				new KotlinNotNullOperatorFilter(),
 				new KotlinDefaultArgumentsFilter(), new KotlinInlineFilter(),
-				new KotlinCoroutineFilter());
+				new KotlinCoroutineFilter(), new KotlinDefaultMethodsFilter());
 	}
 
 	private Filters(final IFilter... filters) {
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinDefaultMethodsFilter.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinDefaultMethodsFilter.java
new file mode 100644
index 00000000..65d783a1
--- /dev/null
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinDefaultMethodsFilter.java
@@ -0,0 +1,46 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2020 Mountainminds GmbH & Co. KG and Contributors
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Evgeny Mandrikov - initial API and implementation
+ *
+ *******************************************************************************/
+package org.jacoco.core.internal.analysis.filter;
+
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+
+/**
+ * Filters methods that Kotlin compiler generates for non-overridden
+ * non-abstract methods of interfaces.
+ */
+final class KotlinDefaultMethodsFilter implements IFilter {
+
+	public void filter(final MethodNode methodNode,
+			final IFilterContext context, final IFilterOutput output) {
+		if (!KotlinGeneratedFilter.isKotlinClass(context)) {
+			return;
+		}
+		new Matcher().match(methodNode, output);
+	}
+
+	private static class Matcher extends AbstractMatcher {
+		private void match(final MethodNode methodNode,
+				final IFilterOutput output) {
+			firstIsALoad0(methodNode);
+			nextIs(Opcodes.INVOKESTATIC);
+			if (cursor != null && ((MethodInsnNode) cursor).owner
+					.endsWith("$DefaultImpls")) {
+				output.ignore(methodNode.instructions.getFirst(),
+						methodNode.instructions.getLast());
+			}
+		}
+	}
+
+}