Add JavascriptFileChecker to selectively skip JavaScript files (#787)

* Add JavascriptFileChecker to selectively skip JavaScript files

* Add test for skipping typescript

Author: timtebeek

build.gradle.kts

@@ -21,6 +21,7 @@ dependencies {
 
     // Limit transitive dependencies for downstream projects like rewrite-spring
     provided("org.openrewrite:rewrite-groovy:${rewriteVersion}")
+    provided("org.openrewrite:rewrite-javascript:${rewriteVersion}")
     provided("org.openrewrite:rewrite-kotlin:${rewriteVersion}")
     provided("org.openrewrite:rewrite-csharp:${rewriteVersion}")
 

src/main/java/org/openrewrite/staticanalysis/RemoveUnusedLocalVariables.java

@@ -27,6 +27,7 @@
 import org.openrewrite.java.MethodMatcher;
 import org.openrewrite.java.service.AnnotationService;
 import org.openrewrite.java.tree.*;
+import org.openrewrite.staticanalysis.javascript.JavascriptFileChecker;
 import org.openrewrite.staticanalysis.kotlin.KotlinFileChecker;
 
 import java.util.Arrays;
@@ -36,6 +37,8 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import static java.util.Collections.singleton;
+import static org.openrewrite.Preconditions.and;
+import static org.openrewrite.Preconditions.not;
 
 @EqualsAndHashCode(callSuper = false)
 @SuppressWarnings("ConstantConditions")
@@ -107,7 +110,8 @@ public TreeVisitor<?, ExecutionContext> getVisitor() {
             ignoreVariableNames.addAll(Arrays.asList(ignoreVariablesNamed));
         }
 
-        return Preconditions.check(Preconditions.not(new KotlinFileChecker<>()), new JavaIsoVisitor<ExecutionContext>() {
+        TreeVisitor<?, ExecutionContext> notJsNorKt = and(not(new JavascriptFileChecker<>()), not(new KotlinFileChecker<>()));
+        return Preconditions.check(notJsNorKt, new JavaIsoVisitor<ExecutionContext>() {
             private Cursor getCursorToParentScope(Cursor cursor) {
                 return cursor.dropParentUntil(is ->
                         is instanceof J.ClassDeclaration ||

src/main/java/org/openrewrite/staticanalysis/javascript/JavascriptFileChecker.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024 the original author or authors.
+ * <p>
+ * Licensed under the Moderne Source Available License (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://docs.moderne.io/licensing/moderne-source-available-license
+ * <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.staticanalysis.javascript;
+
+import org.jspecify.annotations.Nullable;
+import org.openrewrite.Tree;
+import org.openrewrite.TreeVisitor;
+import org.openrewrite.internal.ReflectionUtils;
+import org.openrewrite.javascript.tree.JS;
+import org.openrewrite.marker.SearchResult;
+
+/**
+ * Add a search marker if visiting a JS file
+ */
+public class JavascriptFileChecker<P> extends TreeVisitor<Tree, P> {
+    private static final boolean IS_AVAILABLE = ReflectionUtils.isClassAvailable("org.openrewrite.javascript.tree.JS");
+
+    @Override
+    public @Nullable Tree visit(@Nullable Tree tree, P p) {
+        if (IS_AVAILABLE && tree instanceof JS.CompilationUnit) {
+            return SearchResult.found(tree);
+        }
+        return tree;
+    }
+}

src/test/java/org/openrewrite/staticanalysis/RemoveUnusedLocalVariablesTest.java

@@ -24,6 +24,7 @@
 
 import static org.openrewrite.java.Assertions.java;
 import static org.openrewrite.java.Assertions.version;
+import static org.openrewrite.javascript.Assertions.typescript;
 import static org.openrewrite.kotlin.Assertions.kotlin;
 
 @SuppressWarnings({
@@ -1306,4 +1307,20 @@ fun initializerRemoved() : String {
             );
         }
     }
+
+    @Nested
+    class Typescript {
+        @Test
+        void noChange() {
+            rewriteRun(
+              typescript(
+                """
+                  class Foo {
+                    bar: string;
+                  }
+                  """
+              )
+            );
+        }
+    }
 }