Add missing test coverage for

org.apache.commons.lang3.reflect.TypeUtils.unrollVariables(Map<TypeVariable<?>,
Type>, Type)

Author: garydgregory

src/test/java/org/apache/commons/lang3/reflect/TypeUtilsTest.java

@@ -984,6 +984,15 @@ void testParameterizeNarrowerTypeArray() {
         assertEquals(TypeUtils.parameterize(ArrayList.class, String.class), unrolled);
     }
 
+    @Test
+    void testUnrollVariables() {
+        final TypeVariable<?>[] variables = ArrayList.class.getTypeParameters();
+        final ParameterizedType parameterizedType = TypeUtils.parameterize(ArrayList.class, variables);
+        assertEquals("java.util.ArrayList<E>", TypeUtils.unrollVariables(null, parameterizedType).getTypeName());
+        final Map<TypeVariable<?>, Type> mapping = Collections.<TypeVariable<?>, Type>singletonMap(variables[0], String.class);
+        assertEquals("java.util.ArrayList<java.lang.String>", TypeUtils.unrollVariables(mapping, parameterizedType).getTypeName());
+    }
+
     @Test
     void testParameterizeNullPointerException() {
         assertThrows(NullPointerException.class, () -> TypeUtils.parameterize(null, Collections.emptyMap()));