Fix Es6RewriteClassExtendsExpressions pass to use the recommended traversal

pattern, by just using `shouldTraverse` to traverse only relevant files for the
given language feature.

PiperOrigin-RevId: 601938308

Author: Closure Team

src/com/google/javascript/jscomp/Es6RewriteClassExtendsExpressions.java

@@ -48,8 +48,8 @@
  * <p>TODO(bradfordcsmith): This pass may no longer be necessary once the typechecker passes have
  * all been updated to understand ES6 classes.
  */
-public final class Es6RewriteClassExtendsExpressions extends NodeTraversal.AbstractPostOrderCallback
-    implements CompilerPass {
+public final class Es6RewriteClassExtendsExpressions
+    implements NodeTraversal.Callback, CompilerPass {
 
   static final String CLASS_EXTENDS_VAR = "$classextends$var";
 
@@ -63,9 +63,19 @@ public final class Es6RewriteClassExtendsExpressions extends NodeTraversal.Abstr
     this.astFactory = compiler.createAstFactory();
   }
 
+  
   @Override
   public void process(Node externs, Node root) {
-    TranspilationPasses.processTranspile(compiler, root, features, this);
+    NodeTraversal.traverse(compiler, root, this);
+  }
+
+  @Override
+  public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
+    if (n.isScript()) {
+      FeatureSet scriptFeatures = NodeUtil.getFeatureSetOfScript(n);
+      return scriptFeatures == null || scriptFeatures.contains(features);
+    }
+    return true;
   }
 
   @Override

test/com/google/javascript/jscomp/Es6RewriteClassExtendsExpressionsTest.java

@@ -96,6 +96,40 @@ public void testClassExpressions() {
             "baz(class extends foo.bar {});"));
   }
 
+  @Test
+  public void testClassExtendsClassTranspilation() {
+    String code =
+        lines(
+            "class __PRIVATE_WebChannelConnection extends class __PRIVATE_RestConnection {",
+            "  constructor(e) {",
+            "    this.databaseInfo = e, this.databaseId = e.databaseId;",
+            "  }",
+            "} {",
+            "  constructor(e) {",
+            "    super(e), this.forceLongPolling = e.forceLongPolling, this.autoDetectLongPolling"
+                + " = e.autoDetectLongPolling, this.useFetchStreams = e.useFetchStreams,"
+                + " this.longPollingOptions = e.longPollingOptions;",
+            "    console.log('test');",
+            "  }",
+            "}");
+    String expectedCode =
+        lines(
+            "const testcode$classextends$var0 = class __PRIVATE_RestConnection {",
+            "  constructor(e) {",
+            "    this.databaseInfo = e, this.databaseId = e.databaseId;",
+            "  }",
+            "};",
+            "class __PRIVATE_WebChannelConnection extends testcode$classextends$var0 {",
+            "  constructor(e) {",
+            "    super(e), this.forceLongPolling = e.forceLongPolling, this.autoDetectLongPolling"
+                + " = e.autoDetectLongPolling, this.useFetchStreams = e.useFetchStreams,"
+                + " this.longPollingOptions = e.longPollingOptions;",
+            "    console.log('test');",
+            "  }",
+            "}");
+    test(code, expectedCode);
+  }
+
   @Test
   public void testVarDeclaration() {
     test(

test/com/google/javascript/jscomp/integration/ES2022IntegrationTest.java

@@ -385,4 +385,68 @@ public void computedMethodExecutionOrderAndDeadAssignmentElimination() {
             "  console.log(c.a)",
             "};"));
   }
+
+  @Test
+  public void testEs6RewriteClassExtendsExpression() {
+    CompilerOptions options = createCompilerOptions();
+
+    String code =
+        lines(
+            "/** @unrestricted */",
+            "class __PRIVATE_WebChannelConnection extends class __PRIVATE_RestConnection {",
+            "  constructor(e) {",
+            "    this.databaseInfo = e, this.databaseId = e.databaseId;",
+            "  }",
+            "} {",
+            "  constructor(e) {",
+            "    super(e), this.forceLongPolling = e.forceLongPolling, this.autoDetectLongPolling"
+                + " = e.autoDetectLongPolling, this.useFetchStreams = e.useFetchStreams,"
+                + " this.longPollingOptions = e.longPollingOptions;",
+            "    console.log('test');",
+            "  }",
+            "}");
+    String expectedCodeNonTraspiled =
+        lines(
+            "class __PRIVATE_WebChannelConnection extends class __PRIVATE_RestConnection {",
+            "  constructor(e) {",
+            "    this.databaseInfo = e, this.databaseId = e.databaseId;",
+            "  }",
+            "} {",
+            "  constructor(e) {",
+            "    super(e), this.forceLongPolling = e.forceLongPolling, this.autoDetectLongPolling ="
+                + " ",
+            "    e.autoDetectLongPolling, this.useFetchStreams = e.useFetchStreams,"
+                + " this.longPollingOptions = ",
+            "    e.longPollingOptions;",
+            "    console.log('test');",
+            "  }",
+            "}\n");
+
+    String expectedCodeTranspiled =
+        lines(
+            "const i0$classdecl$var0 = class {",
+            "  constructor(e) {",
+            "    this.databaseInfo = e, this.databaseId = e.databaseId;",
+            "  }",
+            "};",
+            "const i0$classextends$var0 = i0$classdecl$var0;",
+            "class __PRIVATE_WebChannelConnection extends i0$classdecl$var0 {",
+            "  constructor(e) {",
+            "    super(e), this.forceLongPolling = e.forceLongPolling, this.autoDetectLongPolling ="
+                + " ",
+            "    e.autoDetectLongPolling, this.useFetchStreams = e.useFetchStreams,"
+                + " this.longPollingOptions = ",
+            "    e.longPollingOptions;",
+            "    console.log('test');",
+            "  }",
+            "}\n");
+
+    options.setLanguageIn(LanguageMode.UNSTABLE);
+    options.setLanguageOut(LanguageMode.ECMASCRIPT_2019);
+    test(options, code, expectedCodeTranspiled);
+
+    options.setLanguageIn(LanguageMode.UNSTABLE);
+    options.setLanguageOut(LanguageMode.UNSTABLE);
+    test(options, code, expectedCodeNonTraspiled);
+  }
 }