fix #13945 - use local variable instead of casting the object

Author: jdaugherty

grails-plugin-controllers/src/main/groovy/org/grails/compiler/web/ControllerActionTransformer.java

@@ -90,23 +90,11 @@
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.net.URL;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.regex.Pattern;
 
 import static org.codehaus.groovy.ast.tools.GeneralUtils.*;
-import static org.grails.compiler.injection.GrailsASTUtils.applyDefaultMethodTarget;
-import static org.grails.compiler.injection.GrailsASTUtils.applyMethodTarget;
-import static org.grails.compiler.injection.GrailsASTUtils.buildGetMapExpression;
-import static org.grails.compiler.injection.GrailsASTUtils.buildGetPropertyExpression;
-import static org.grails.compiler.injection.GrailsASTUtils.buildSetPropertyExpression;
-import static org.grails.compiler.injection.GrailsASTUtils.hasAnnotation;
-import static org.grails.compiler.injection.GrailsASTUtils.hasParameters;
-import static org.grails.compiler.injection.GrailsASTUtils.isInheritedFromTrait;
-import static org.grails.compiler.injection.GrailsASTUtils.removeAnnotation;
+import static org.grails.compiler.injection.GrailsASTUtils.*;
 
 /**
  * Enhances controller classes by converting closures actions to method actions and binding
@@ -798,14 +786,12 @@ protected void initializeAndValidateCommandObjectParameter(final BlockStatement
             }
 
             if (argumentIsValidateable) {
-                final MethodCallExpression validateMethodCallExpression =
-                        new MethodCallExpression(new VariableExpression(paramName), "validate", EMPTY_TUPLE);
-                final MethodNode validateMethod =
-                        commandObjectNode.getMethod("validate", new Parameter[0]);
+                final MethodCallExpression validateMethodCallExpression = callX(localVarX(paramName, commandObjectNode), "validate");
+                final MethodNode validateMethod = commandObjectNode.getMethod("validate", new Parameter[0]);
                 if (validateMethod != null) {
                     validateMethodCallExpression.setMethodTarget(validateMethod);
                 }
-                final Statement ifCommandObjectIsNotNullThenValidate = new IfStatement(new BooleanExpression(new VariableExpression(paramName)), new ExpressionStatement(validateMethodCallExpression), new ExpressionStatement(new EmptyExpression()));
+                final Statement ifCommandObjectIsNotNullThenValidate = ifS(boolX(varX(paramName)), stmt(validateMethodCallExpression));
                 wrapper.addStatement(ifCommandObjectIsNotNullThenValidate);
             } else {
                 // try to dynamically invoke the .validate() method if it is available at runtime...

grails-test-suite-web/src/test/groovy/org/grails/web/commandobjects/CommandObjectsSpec.groovy

@@ -5,7 +5,6 @@ import grails.testing.gorm.DataTest
 import grails.testing.web.controllers.ControllerUnitTest
 import grails.validation.Validateable
 import spock.lang.Issue
-import spock.lang.PendingFeature
 import spock.lang.Specification
 
 class CommandObjectsSpec extends Specification implements ControllerUnitTest<TestController>, DataTest {
@@ -323,7 +322,6 @@ class CommandObjectsSpec extends Specification implements ControllerUnitTest<Tes
         model.pId == 2
     }
 
-    @PendingFeature()
     @Issue('https://github.com/grails/grails-core/issues/13945')
     void "calling actions involving inherited command objects - parent command"() {
         given: