defaultValue for @RequestParam implies required=false (#179)

* defaultValue for @RequestParam implies required=false

This was not handled correctly for non primitive types annotated
with @RequestParam.

* Restructure condition to enhance redability

Author: Jean-Pierre Bergamin

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/request/RequestParametersSnippet.java

@@ -46,9 +46,19 @@ public RequestParametersSnippet failOnUndocumentedParams(boolean failOnUndocumen
 
     @Override
     protected boolean isRequired(MethodParameter param, RequestParam annot) {
-        return param.getParameterType().isPrimitive()
-                ? ValueConstants.DEFAULT_NONE.equals(annot.defaultValue())
-                : annot.required();
+        if (hasDefaultValue(annot)) {
+            // Having a defaultValue set implies required=false
+            return false;
+        } else if (param.getParameterType().isPrimitive()) {
+            // A primitive type is required if no defaultValue is set, regardless of the value of the required flag
+            return true;
+        } else {
+            return annot.required();
+        }
+    }
+
+    private static boolean hasDefaultValue(RequestParam annot) {
+        return !ValueConstants.DEFAULT_NONE.equals(annot.defaultValue());
     }
 
     @Override

spring-auto-restdocs-core/src/test/java/capital/scalable/restdocs/request/RequestParametersSnippetTest.java

@@ -118,6 +118,27 @@ public void simpleRequestWithPrimitivesDefaultValueParameterNotDocumented() thro
                 .build());
     }
 
+    @Test
+    public void simpleRequestWithStringDefaultValueParameter() throws Exception {
+        HandlerMethod handlerMethod = createHandlerMethod("searchItem2String", double.class,
+                boolean.class, String.class);
+        initParameters(handlerMethod);
+        mockParamComment("searchItem2String", "param1", "A decimal");
+        mockParamComment("searchItem2String", "param2", "A boolean");
+        mockParamComment("searchItem2String", "param3", "A String");
+
+        this.snippets.expect(REQUEST_PARAMETERS).withContents(
+                tableWithHeader("Parameter", "Type", "Optional", "Description")
+                        .row("param1", "Decimal", "false", "A decimal.")
+                        .row("param2", "Boolean", "false", "A boolean.")
+                        .row("param3", "String", "true", "A String.\n\nDefault value: \"de\"."));
+
+        new RequestParametersSnippet().document(operationBuilder
+                .attribute(HandlerMethod.class.getName(), handlerMethod)
+                .attribute(JavadocReader.class.getName(), javadocReader)
+                .attribute(ConstraintReader.class.getName(), constraintReader)
+                .build());
+    }
     @Test
     public void noParameters() throws Exception {
         HandlerMethod handlerMethod = createHandlerMethod("items");
@@ -239,6 +260,12 @@ public void searchItem2(@RequestParam double param1,    // required
             // NOOP
         }
 
+        public void searchItem2String(@RequestParam double param1,    // required
+                                @RequestParam(required = false) boolean param2, // required anyway
+                                @RequestParam(defaultValue = "de") String param3) { // not required
+            // NOOP
+        }
+
         public void items() {
             // NOOP
         }