OpenRewrite recipe best practices (#949)

* OpenRewrite recipe best practices

Use this link to re-run the recipe: https://app.moderne.io/recipes/org.openrewrite.recipes.rewrite.OpenRewriteRecipeBestPractices?organizationId=QUxML01vZGVybmUvTW9kZXJuZSArIE9wZW5SZXdyaXRl

Co-authored-by: Moderne <team@moderne.io>

* Fix compilation errors: cast visitor return type to MethodDeclaration

RemoveAnnotationVisitor.visit() and RemoveAnnotation.getVisitor().visit()
return generic J, but the calling methods expect J.MethodDeclaration.
Added explicit casts in three files to match the existing pattern.

---------

Co-authored-by: Moderne <team@moderne.io>

Author: timtebeek

src/main/java/org/openrewrite/java/testing/cleanup/RemoveTestPrefix.java

@@ -148,7 +148,7 @@ public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, Atomi
                     }
                     return super.visitMethodInvocation(method, atomicBoolean);
                 }
-            }.visitMethodDeclaration(m, skip);
+            }.visit(m, skip, getCursor().getParentTreeCursor());
             if (skip.get()) {
                 return m;
             }

src/main/java/org/openrewrite/java/testing/junit5/AddParameterizedTestAnnotation.java

@@ -80,7 +80,7 @@ public J.MethodDeclaration visitMethodDeclaration(J.MethodDeclaration md, Execut
 
             // Remove @Test annotation if present
             maybeAddImport("org.junit.jupiter.params.ParameterizedTest");
-            return new RemoveAnnotationVisitor(TEST_ANNOTATION_MATCHER).visitMethodDeclaration(m, ctx);
+            return (J.MethodDeclaration) new RemoveAnnotationVisitor(TEST_ANNOTATION_MATCHER).visit(m, ctx, getCursor().getParentTreeCursor());
         }
     }
 }

src/main/java/org/openrewrite/java/testing/junit5/RemoveDuplicateTestTemplates.java

@@ -51,7 +51,7 @@ public J.MethodDeclaration visitMethodDeclaration(J.MethodDeclaration md, Execut
             if (m.getLeadingAnnotations().stream().anyMatch(TEST_ANNOTATION_MATCHER::matches) &&
                 m.getLeadingAnnotations().stream().anyMatch(REPEATED_TEST_ANNOTATION_MATCHER::matches)) {
                 maybeRemoveImport("org.junit.jupiter.api.Test");
-                return new RemoveAnnotationVisitor(TEST_ANNOTATION_MATCHER).visitMethodDeclaration(m, ctx);
+                return (J.MethodDeclaration) new RemoveAnnotationVisitor(TEST_ANNOTATION_MATCHER).visit(m, ctx, getCursor().getParentTreeCursor());
             }
             return m;
         }

src/main/java/org/openrewrite/java/testing/junit6/MinimumJreConditions.java

@@ -188,7 +188,7 @@ public J.CompilationUnit visitCompilationUnit(J.CompilationUnit cu, ExecutionCon
             private J.MethodDeclaration removeAnnotation(J.MethodDeclaration m, String annotationType, ExecutionContext ctx) {
                 RemoveAnnotation removeAnnotation = new RemoveAnnotation("@" + annotationType);
                 maybeRemoveImport(JRE_IMPORT);
-                return removeAnnotation.getVisitor().visitMethodDeclaration(m, ctx);
+                return (J.MethodDeclaration) removeAnnotation.getVisitor().visit(m, ctx, getCursor().getParentTreeCursor());
             }
 
             private J.MethodDeclaration updateAnnotationVersions(J.MethodDeclaration m, List<String> versions, String annotationType, ExecutionContext ctx) {

src/main/java/org/openrewrite/java/testing/mockito/ArgumentMatcherToLambda.java

@@ -26,10 +26,10 @@
 import org.openrewrite.marker.Markers;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 import static java.util.Collections.emptyList;
+import static java.util.Collections.singletonList;
 import static org.openrewrite.Tree.randomId;
 
 public class ArgumentMatcherToLambda extends Recipe {
@@ -118,7 +118,7 @@ public J visitNewClass(J.NewClass newClass, ExecutionContext ctx) {
                         J.Lambda.Parameters lambdaParams = new J.Lambda.Parameters(
                                 randomId(), Space.EMPTY, Markers.EMPTY,
                                 false,
-                                Collections.singletonList(JRightPadded.build(lambdaParam))
+                                singletonList(JRightPadded.build(lambdaParam))
                         );
 
                         J.Lambda lambda = new J.Lambda(

src/main/java/org/openrewrite/java/testing/mockito/PowerMockRunnerDelegateToRunWith.java

@@ -29,9 +29,10 @@
 import org.openrewrite.java.tree.Expression;
 import org.openrewrite.java.tree.J;
 
-import java.util.Collections;
 import java.util.List;
 
+import static java.util.Collections.singletonList;
+
 public class PowerMockRunnerDelegateToRunWith extends Recipe {
 
     private static final String POWER_MOCK_RUNNER_DELEGATE = "org.powermock.modules.junit4.PowerMockRunnerDelegate";
@@ -74,7 +75,7 @@ public J.ClassDeclaration visitClassDeclaration(J.ClassDeclaration classDecl, Ex
                             maybeRemoveImport(POWER_MOCK_RUNNER_DELEGATE);
                             return cd.withLeadingAnnotations(ListUtils.map(cd.getLeadingAnnotations(), annotation -> {
                                 if (RUN_WITH_POWER_MOCK_RUNNER_MATCHER.matches(annotation)) {
-                                    return annotation.withArguments(Collections.singletonList(delegateRunnerArg));
+                                    return annotation.withArguments(singletonList(delegateRunnerArg));
                                 }
                                 if (DELEGATE_MATCHER.matches(annotation)) {
                                     return null;

src/main/java/org/openrewrite/java/testing/mockito/PowerMockWhiteboxToJavaReflection.java

@@ -19,7 +19,10 @@
 import org.jspecify.annotations.Nullable;
 import org.openrewrite.*;
 import org.openrewrite.internal.ListUtils;
-import org.openrewrite.java.*;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.java.JavaTemplate;
+import org.openrewrite.java.MethodMatcher;
 import org.openrewrite.java.search.UsesType;
 import org.openrewrite.java.tree.*;
 import org.openrewrite.marker.Markers;

src/main/java/org/openrewrite/java/testing/mockito/RemovePowerMockClassExtensions.java

@@ -50,8 +50,7 @@ public TreeVisitor<?, ExecutionContext> getVisitor() {
                     public J.ClassDeclaration visitClassDeclaration(J.ClassDeclaration classDecl, ExecutionContext ctx) {
                         J.ClassDeclaration cd = super.visitClassDeclaration(classDecl, ctx);
                         cd = maybeRemoveExtension(cd, POWER_MOCK_CONFIG);
-                        cd = maybeRemoveExtension(cd, POWER_MOCK_TEST_CASE);
-                        return cd;
+                        return maybeRemoveExtension(cd, POWER_MOCK_TEST_CASE);
                     }
 
                     private J.ClassDeclaration maybeRemoveExtension(J.ClassDeclaration classDecl, String extensionFQN) {

src/main/resources/META-INF/rewrite/examples.yml

@@ -4690,6 +4690,38 @@ examples:
     language: java
 ---
 type: specs.openrewrite.org/v1beta/example
+recipeName: org.openrewrite.java.testing.mockito.PowerMockWhiteboxToJavaReflection
+examples:
+- description: '`PowerMockWhiteboxToJavaReflectionTest#setInternalStateReplacedWithReflection`'
+  sources:
+  - before: |
+      class MyService {
+          private String name;
+      }
+    language: java
+  - before: |
+      import org.powermock.reflect.Whitebox;
+
+      class MyServiceTest {
+          void testSetField() {
+              MyService service = new MyService();
+              Whitebox.setInternalState(service, "name", "expectedValue");
+          }
+      }
+    after: |
+      import java.lang.reflect.Field;
+
+      class MyServiceTest {
+          void testSetField() throws Exception {
+              MyService service = new MyService();
+              Field nameField = service.getClass().getDeclaredField("name");
+              nameField.setAccessible(true);
+              nameField.set(service, "expectedValue");
+          }
+      }
+    language: java
+---
+type: specs.openrewrite.org/v1beta/example
 recipeName: org.openrewrite.java.testing.mockito.PowerMockitoMockStaticToMockito
 examples:
 - description: '`PowerMockitoMockStaticToMockitoTest#prepareForTestAnnotationIsReplacedBySingleField`'

src/test/java/org/openrewrite/java/testing/assertj/AdoptAssertJDurationAssertionsTest.java

@@ -251,7 +251,7 @@ void testMethod(Temporal timestampA, Temporal timestampB) {
     @ParameterizedTest
     void simplifyDurationAssertions(String before, String after) {
         //language=java
-        String template = """
+        var template = """
           import java.time.Duration;
 
           import static org.assertj.core.api.Assertions.assertThat;