Add requireFactory method to MarkwonSpansFactory

markwon-core/src/main/java/ru/noties/markwon/MarkwonSpansFactory.java

@@ -40,6 +40,17 @@ public interface MarkwonSpansFactory {
         @Nullable
         <N extends Node> SpanFactory getFactory(@NonNull Class<N> node);
 
+        /**
+         * To obtain current {@link SpanFactory} associated with specified node. Can be used
+         * when SpanFactory must be present for node. If it\'s not added/registered a runtime
+         * exception will be thrown
+         *
+         * @see #getFactory(Class)
+         * @since 3.0.1-SNAPSHOT
+         */
+        @NonNull
+        <N extends Node> SpanFactory requireFactory(@NonNull Class<N> node);
+
         @NonNull
         MarkwonSpansFactory build();
     }

markwon-core/src/main/java/ru/noties/markwon/MarkwonSpansFactoryImpl.java

@@ -58,6 +58,16 @@ class MarkwonSpansFactoryImpl implements MarkwonSpansFactory {
             return factories.get(node);
         }
 
+        @NonNull
+        @Override
+        public <N extends Node> SpanFactory requireFactory(@NonNull Class<N> node) {
+            final SpanFactory factory = getFactory(node);
+            if (factory == null) {
+                throw new NullPointerException(node.getName());
+            }
+            return factory;
+        }
+
         @NonNull
         @Override
         public MarkwonSpansFactory build() {