better msg

Author: wied03

src/test/java/org/primeframework/mvc/test/BodyTools.java

@@ -106,10 +106,10 @@ public static String processTemplateWithMap(Path path, DetectionMap values, bool
       Set<Object> unusedVariables = values.getUnusedVariables("_",
                                                               "actual");
       if (!unusedVariables.isEmpty()) {
-        throw new IllegalArgumentException("The following variables are not used in the [%s] template: %s".formatted(path,
-                                                                                                                     unusedVariables.stream()
-                                                                                                                                    .sorted()
-                                                                                                                                    .toList()));
+        throw new IllegalArgumentException("Variables %s are not used in the [%s] template. If it's acceptable for the variable to not be used, wrap it in an Optional".formatted(unusedVariables.stream()
+                                                                                                                                                                                                 .sorted()
+                                                                                                                                                                                                 .toList(),
+                                                                                                                                                                                  path));
       }
       return writer.toString();
     } catch (TemplateException e) {

src/test/java/org/primeframework/mvc/test/BodyToolsTest.java

@@ -101,7 +101,7 @@ public void processTemplateWithMap_unused_variables() throws Exception {
     } catch (Exception e) {
       assertEquals(e.getClass(), IllegalArgumentException.class,
                    "Expected this exception type");
-      assertEquals(e.getMessage(), "The following variables are not used in the [src/test/web/templates/echo.ftl] template: [othervariable]",
+      assertEquals(e.getMessage(), "Variables [othervariable] are not used in the [src/test/web/templates/echo.ftl] template. If it's acceptable for the variable to not be used, wrap it in an Optional",
                    "othervariable is in the map but is not used");
     }
   }