Add NotationRegistryTest

pgpainless-core/src/main/java/org/pgpainless/util/NotationRegistry.java

@@ -41,6 +41,12 @@ public final class NotationRegistry {
         return INSTANCE;
     }
 
+    /**
+     * Add a known notation name into the registry.
+     * This will cause critical notations with that name to no longer invalidate the signature.
+     *
+     * @param notationName name of the notation
+     */
     public void addKnownNotation(String notationName) {
         if (notationName == null) {
             throw new NullPointerException("Notation name MUST NOT be null.");
@@ -48,7 +54,20 @@ public final class NotationRegistry {
         knownNotations.add(notationName);
     }
 
+    /**
+     * Return true if the notation name is registered in the registry.
+     *
+     * @param notationName name of the notation
+     * @return true if notation is known, false otherwise.
+     */
     public boolean isKnownNotation(String notationName) {
         return knownNotations.contains(notationName);
     }
+
+    /**
+     * Clear all known notations from the registry.
+     */
+    public void clear() {
+        knownNotations.clear();
+    }
 }

pgpainless-core/src/test/java/org/pgpainless/util/NotationRegistryTest.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2021 Paul Schaub.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.pgpainless.util;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class NotationRegistryTest {
+
+    @BeforeEach
+    public void setup() {
+        NotationRegistry.getInstance().clear();
+    }
+
+    @Test
+    public void notationIsKnownOnceAddedAndUnknownOnceCleared() {
+        NotationRegistry registry = NotationRegistry.getInstance();
+
+        assertFalse(registry.isKnownNotation("proof@metacode.biz"), "Notation is initially not known.");
+        assertFalse(registry.isKnownNotation("unkown@notation.data"));
+
+        registry.addKnownNotation("proof@metacode.biz");
+        assertTrue(registry.isKnownNotation("proof@metacode.biz"), "Notation is known after it has been added to the registry.");
+        assertFalse(registry.isKnownNotation("unknown@notation.data"));
+
+        registry.clear();
+        assertFalse(registry.isKnownNotation("proof@metacode.biz"), "Notation is no longer known after registry is cleared.");
+        assertFalse(registry.isKnownNotation("unknown@notation.data"));
+    }
+}