adjusting MaybeAddJakartaServletApi to be a ScanningRecipe so that it can correctly apply its precondition to the AddDependency recipe (#255)

Author: nmck257

src/main/java/org/openrewrite/java/migrate/jakarta/MaybeAddJakartaServletApi.java

@@ -15,17 +15,12 @@
  */
 package org.openrewrite.java.migrate.jakarta;
 
-import org.openrewrite.ExecutionContext;
-import org.openrewrite.Preconditions;
-import org.openrewrite.Recipe;
-import org.openrewrite.TreeVisitor;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.openrewrite.*;
 import org.openrewrite.maven.AddDependency;
 import org.openrewrite.maven.search.DoesNotIncludeDependency;
 
-import java.util.Collections;
-import java.util.List;
-
-public class MaybeAddJakartaServletApi extends Recipe {
+public class MaybeAddJakartaServletApi extends ScanningRecipe<AddDependency.Scanned> {
 
     @Override
     public String getDisplayName() {
@@ -37,26 +32,38 @@ public String getDescription() {
         return "Adds the `jakarta.servlet-api` dependency, unless the project already uses `spring-boot-starter-web`, which transitively includes a compatible implementation under a different GAV.";
     }
 
+    @JsonIgnore
+    private final AddDependency addDependency = new AddDependency(
+            "jakarta.servlet",
+            "jakarta.servlet-api",
+            "6.x",
+            null,
+            null,
+            null,
+            "javax.servlet.*",
+            null,
+            null,
+            null,
+            null,
+            true
+    );
+
+    @Override
+    public AddDependency.Scanned getInitialValue(ExecutionContext ctx) {
+        return addDependency.getInitialValue(ctx);
+    }
+
     @Override
-    public TreeVisitor<?, ExecutionContext> getVisitor() {
-        return Preconditions.check(new DoesNotIncludeDependency("org.springframework.boot", "spring-boot-starter-web", null, null), TreeVisitor.noop());
+    public TreeVisitor<?, ExecutionContext> getScanner(AddDependency.Scanned acc) {
+        return addDependency.getScanner(acc);
     }
 
     @Override
-    public List<Recipe> getRecipeList() {
-        return Collections.singletonList(new AddDependency(
-                "jakarta.servlet",
-                "jakarta.servlet-api",
-                "6.x",
-                null,
-                null,
-                null,
-                "javax.servlet.*",
-                null,
-                null,
-                null,
-                null,
-                true
-        ));
+    public TreeVisitor<?, ExecutionContext> getVisitor(AddDependency.Scanned acc) {
+        return Preconditions.check(
+                new DoesNotIncludeDependency("org.springframework.boot", "spring-boot-starter-web", null, null),
+                addDependency.getVisitor(acc)
+        );
     }
-}
+
+}

src/test/java/org/openrewrite/java/migrate/jakarta/MaybeAddJakartaServletApiTest.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2023 the original author or authors.
+ * <p>
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.openrewrite.java.migrate.jakarta;
+
+import org.junit.jupiter.api.Test;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.test.RecipeSpec;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.*;
+import static org.openrewrite.maven.Assertions.pomXml;
+
+class MaybeAddJakartaServletApiTest implements RewriteTest {
+    @Override
+    public void defaults(RecipeSpec spec) {
+        spec.recipe(new MaybeAddJakartaServletApi())
+          .parser(JavaParser.fromJavaVersion()
+            .dependsOn("package javax.servlet;\npublic class Filter {}"));
+    }
+
+    @Test
+    void hasSpringBootStarterWeb() {
+        rewriteRun(
+          mavenProject("my-project",
+            srcMainJava(java("""
+              import javax.servlet.Filter;
+              class A {
+                  Filter foo = null;
+              }
+              """)),
+            pomXml("""
+              <?xml version="1.0" encoding="UTF-8"?>
+              <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+                <modelVersion>4.0.0</modelVersion>
+                <groupId>org.sample</groupId>
+                <artifactId>sample</artifactId>
+                <version>1.0.0</version>
+
+                <dependencies>
+                  <dependency>
+                    <groupId>org.springframework.boot</groupId>
+                    <artifactId>spring-boot-starter-web</artifactId>
+                    <version>2.7.0</version>
+                  </dependency>
+                </dependencies>
+
+              </project>
+              """)
+          )
+        );
+    }
+
+    @Test
+    void doesNotHaveSpringBootStarterWeb() {
+        rewriteRun(
+          mavenProject("my-project",
+            srcMainJava(java("""
+              import javax.servlet.Filter;
+              class A {
+                  Filter foo = null;
+              }
+              """)),
+            pomXml("""
+                <?xml version="1.0" encoding="UTF-8"?>
+                <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+                  <modelVersion>4.0.0</modelVersion>
+                  <groupId>org.sample</groupId>
+                  <artifactId>sample</artifactId>
+                  <version>1.0.0</version>
+    
+                  <dependencies>
+                  </dependencies>
+    
+                </project>
+                """,
+              """
+                <?xml version="1.0" encoding="UTF-8"?>
+                <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+                  <modelVersion>4.0.0</modelVersion>
+                  <groupId>org.sample</groupId>
+                  <artifactId>sample</artifactId>
+                  <version>1.0.0</version>
+
+                  <dependencies>
+                    <dependency>
+                      <groupId>jakarta.servlet</groupId>
+                      <artifactId>jakarta.servlet-api</artifactId>
+                      <version>6.0.0</version>
+                    </dependency>
+                  </dependencies>
+
+                </project>
+                """)
+          )
+        );
+    }
+}