1 files changed, 6 insertions, 0 deletions
diff --git a/org.jacoco.cli.test/src/org/jacoco/cli/internal/CommandTestBase.java b/org.jacoco.cli.test/src/org/jacoco/cli/internal/CommandTestBase.java
index 4d12a373..2dee3adf 100644
--- a/org.jacoco.cli.test/src/org/jacoco/cli/internal/CommandTestBase.java
+++ b/org.jacoco.cli.test/src/org/jacoco/cli/internal/CommandTestBase.java
@@ -12,6 +12,7 @@
 package org.jacoco.cli.internal;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 import java.io.PrintWriter;
@@ -59,6 +60,11 @@ public abstract class CommandTestBase {
 		assertTrue(content, content.contains(expected));
 	}
 
+	protected void assertContainsNot(String expected, StringWriter buffer) {
+		final String content = buffer.toString();
+		assertFalse(content, content.contains(expected));
+	}
+
 	protected String getClassPath() {
 		final String name = getClass().getName();
 		final String res = "/" + name.replace('.', '/') + ".class";