Add filter for Kotlin "unsafe" cast operator (#761)

6 files changed, 186 insertions, 1 deletions

diff --git a/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/KotlinUnsafeCastOperatorTest.java b/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/KotlinUnsafeCastOperatorTest.java
new file mode 100644
index 00000000..475d902b
--- /dev/null
+++ b/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/KotlinUnsafeCastOperatorTest.java
@@ -0,0 +1,26 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2018 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.test.validation.kotlin;
+
+import org.jacoco.core.test.validation.ValidationTestBase;
+import org.jacoco.core.test.validation.kotlin.targets.KotlinUnsafeCastOperatorTarget;
+
+/**
+ * Test of "unsafe" cast operator.
+ */
+public class KotlinUnsafeCastOperatorTest extends ValidationTestBase {
+
+	public KotlinUnsafeCastOperatorTest() {
+		super(KotlinUnsafeCastOperatorTarget.class);
+	}
+
+}
diff --git a/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/targets/KotlinUnsafeCastOperatorTarget.kt b/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/targets/KotlinUnsafeCastOperatorTarget.kt
new file mode 100644
index 00000000..a4f5ccda
--- /dev/null
+++ b/org.jacoco.core.test.validation.kotlin/src/org/jacoco/core/test/validation/kotlin/targets/KotlinUnsafeCastOperatorTarget.kt
@@ -0,0 +1,28 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2018 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.test.validation.kotlin.targets
+
+/**
+ * This test target is "unsafe" cast operator.
+ */
+object KotlinUnsafeCastOperatorTarget {
+
+    private fun nullable(): String? {
+        return ""
+    }
+
+    @JvmStatic
+    fun main(args: Array<String>) {
+        nullable() as String // assertFullyCovered()
+    }
+
+}
diff --git a/org.jacoco.core.test/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilterTest.java b/org.jacoco.core.test/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilterTest.java
new file mode 100644
index 00000000..eb942519
--- /dev/null
+++ b/org.jacoco.core.test/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilterTest.java
@@ -0,0 +1,52 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2018 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.jacoco.core.internal.instr.InstrSupport;
+import org.junit.Test;
+import org.objectweb.asm.Label;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+
+/**
+ * Unit tests for {@link KotlinUnsafeCastOperatorFilter}.
+ */
+public class KotlinUnsafeCastOperatorFilterTest extends FilterTestBase {
+
+	private final KotlinUnsafeCastOperatorFilter filter = new KotlinUnsafeCastOperatorFilter();
+
+	private final MethodNode m = new MethodNode(InstrSupport.ASM_API_VERSION, 0,
+			"name", "()V", null, null);
+
+	@Test
+	public void should_filter() {
+		final Label label = new Label();
+
+		m.visitInsn(Opcodes.DUP);
+		m.visitJumpInsn(Opcodes.IFNONNULL, label);
+		final AbstractInsnNode expectedFrom = m.instructions.getLast();
+		m.visitTypeInsn(Opcodes.NEW, "kotlin/TypeCastException");
+		m.visitInsn(Opcodes.DUP);
+		m.visitLdcInsn("null cannot be cast to non-null type kotlin.String");
+		m.visitMethodInsn(Opcodes.INVOKESPECIAL, "kotlin/TypeCastException",
+				"<init>", "(Ljava/lang/String;)V", false);
+		m.visitInsn(Opcodes.ATHROW);
+		final AbstractInsnNode expectedTo = m.instructions.getLast();
+		m.visitLabel(label);
+
+		filter.filter(m, context, output);
+
+		assertIgnored(new Range(expectedFrom, expectedTo));
+	}
+
+}
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 03c85d7d..f6a7a1df 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
@@ -34,7 +34,8 @@ public final class Filters implements IFilter {
 			new StringSwitchJavacFilter(), new StringSwitchEcjFilter(),
 			new EnumEmptyConstructorFilter(), new AnnotationGeneratedFilter(),
 			new KotlinGeneratedFilter(), new KotlinLateinitFilter(),
-			new KotlinWhenFilter(), new KotlinWhenStringFilter());
+			new KotlinWhenFilter(), new KotlinWhenStringFilter(),
+			new KotlinUnsafeCastOperatorFilter());
 
 	private final IFilter[] filters;
 
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilter.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilter.java
new file mode 100644
index 00000000..b65cac27
--- /dev/null
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/KotlinUnsafeCastOperatorFilter.java
@@ -0,0 +1,71 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2018 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.JumpInsnNode;
+import org.objectweb.asm.tree.LdcInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+
+/**
+ * Filters branch in bytecode that Kotlin compiler generates for "unsafe" cast
+ * operator.
+ */
+public final class KotlinUnsafeCastOperatorFilter implements IFilter {
+
+	private static final String KOTLIN_TYPE_CAST_EXCEPTION = "kotlin/TypeCastException";
+
+	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;
+
+			nextIsNew(KOTLIN_TYPE_CAST_EXCEPTION);
+			nextIs(Opcodes.DUP);
+			nextIs(Opcodes.LDC);
+			if (cursor == null) {
+				return;
+			}
+			final LdcInsnNode ldc = (LdcInsnNode) cursor;
+			if (!(ldc.cst instanceof String && ((String) ldc.cst)
+					.startsWith("null cannot be cast to non-null type"))) {
+				return;
+			}
+			nextIsInvokeSuper(KOTLIN_TYPE_CAST_EXCEPTION,
+					"(Ljava/lang/String;)V");
+			nextIs(Opcodes.ATHROW);
+			if (cursor == null) {
+				return;
+			}
+			if (cursor.getNext() != ((JumpInsnNode) start).label) {
+				return;
+			}
+
+			output.ignore(start, cursor);
+		}
+	}
+
+}
diff --git a/org.jacoco.doc/docroot/doc/changes.html b/org.jacoco.doc/docroot/doc/changes.html
index dc364940..94184856 100644
--- a/org.jacoco.doc/docroot/doc/changes.html
+++ b/org.jacoco.doc/docroot/doc/changes.html
@@ -20,6 +20,13 @@
 
 <h2>Snapshot Build @qualified.bundle.version@ (@build.date@)</h2>
 
+<h3>New Features</h3>
+<ul>
+  <li>Branch added by the Kotlin compiler for "unsafe" cast operator is filtered
+      out during generation of report
+      (GitHub <a href="https://github.com/jacoco/jacoco/issues/761">#761</a>).</li>
+</ul>
+
 <h2>Release 0.8.2 (2018/08/21)</h2>
 
 <h3>New Features</h3>