Move es6RewriteArrowFunction pass post normalize

PiperOrigin-RevId: 623500740

Author: rishipal

src/com/google/javascript/jscomp/Es6RewriteArrowFunction.java

@@ -103,11 +103,7 @@ private void visitArrowFunction(NodeTraversal t, Node n, ThisAndArgumentsContext
     n.setIsArrowFunction(false);
 
     Node body = n.getLastChild();
-    if (!body.isBlock()) {
-      body.detach();
-      body = IR.block(IR.returnNode(body)).srcrefTreeIfMissing(body);
-      n.addChildToBack(body);
-    }
+    checkState(body.isBlock(), "Arrow function body must be a block after normalization");
 
     ThisAndArgumentsReferenceUpdater updater =
         new ThisAndArgumentsReferenceUpdater(compiler, context, astFactory);

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

@@ -203,9 +203,6 @@ public static void addEarlyOptimizationTranspilationPasses(
     if (options.needsTranspilationOf(Feature.NEW_TARGET)) {
       passes.maybeAdd(rewriteNewDotTarget);
     }
-    if (options.needsTranspilationOf(Feature.ARROW_FUNCTIONS)) {
-      passes.maybeAdd(es6RewriteArrowFunction);
-    }
   }
 
   /**
@@ -219,6 +216,10 @@ public static void addPostNormalizationTranspilationPasses(
     // TODO(b/197349249): Move passes from `addEarlyOptimizationTranspilationPasses()` to here
     // until that method can be deleted as a no-op.
 
+    if (options.needsTranspilationOf(Feature.ARROW_FUNCTIONS)) {
+      passes.maybeAdd(es6RewriteArrowFunction);
+    }
+
     if (options.needsTranspilationOf(Feature.CLASSES)) {
       passes.maybeAdd(es6RewriteClass);
     }

test/com/google/javascript/jscomp/Es6RewriteArrowFunctionTest.java

@@ -39,6 +39,7 @@ public void setUp() throws Exception {
     setAcceptedLanguage(LanguageMode.ECMASCRIPT_2015);
     languageOut = LanguageMode.ECMASCRIPT3;
 
+    enableNormalize();
     enableTypeInfoValidation();
     enableTypeCheck();
     replaceTypesWithColors();
@@ -280,9 +281,9 @@ public void testCapturingThisInArrowFromClassConstructorWithSuperCall() {
             "  }",
             "}",
             "class C extends B {",
-            "  constructor(x, y) {",
+            "  constructor(x$jscomp$1, y) {",
             "    console.log('statement before super');",
-            "    super(x);",
+            "    super(x$jscomp$1);",
             "    const $jscomp$this$UID$2 = this;", // Must not use `this` before super() call.
             "    this.wrappedXGetter = function() { return $jscomp$this$UID$2.x; };",
             "    this.y = y;",
@@ -325,11 +326,11 @@ public void testCapturingThisInArrowFromClassConstructorWithMultipleSuperCallPat
             "  }",
             "}",
             "class C extends B {",
-            "  constructor(x, y) {",
-            "    if (x < 1) {",
-            "      super(x);",
+            "  constructor(x$jscomp$1, y) {",
+            "    if (x$jscomp$1 < 1) {",
+            "      super(x$jscomp$1);",
             "    } else {",
-            "      super(-x);",
+            "      super(-x$jscomp$1);",
             "    }",
             "    const $jscomp$this$UID$2 = this;", // Must not use `this` before super() call.
             "    this.wrappedXGetter = function() { return $jscomp$this$UID$2.x; };",
@@ -343,7 +344,8 @@ public void testCapturingThisInArrowFromClassConstructorWithMultipleSuperCallPat
   public void testMultipleArrowsInSameFreeScope() {
     testArrowRewriting(
         "var a1 = x => x+1; var a2 = x => x-1;",
-        "var a1 = function(x) { return x+1; }; var a2 = function(x) { return x-1; };");
+        "var a1 = function(x) { return x+1; }; var a2 = function(x$jscomp$1) { return x$jscomp$1-1;"
+            + " };");
   }
 
   @Test
@@ -353,7 +355,7 @@ public void testMultipleArrowsInSameFunctionScope() {
         lines(
             "function f() {",
             "  var a1 = function(x) { return x+1; };",
-            "  var a2 = function(x) { return x-1; };",
+            "  var a2 = function(x$jscomp$1) { return x$jscomp$1-1; };",
             "}"));
   }
 
@@ -423,7 +425,8 @@ public void testPassingMultipleArrowsInSameFreeScopeAsMethodParams() {
         expected(
             lines(
                 "var a = [1,2,3,4];",
-                "var b = a.map(function(x) { return x+1; }).map(function(x) { return x*x; });")));
+                "var b = a.map(function(x) { return x+1; }).map(function(x$jscomp$1) { return"
+                    + " x$jscomp$1*x$jscomp$1; });")));
   }
 
   @Test
@@ -448,7 +451,8 @@ public void testMultipleArrowsInSameFunctionScopeAsMethodParams() {
             lines(
                 "function f() {",
                 "  var a = [1,2,3,4];",
-                "  var b = a.map(function(x) { return x+1; }).map(function(x) { return x*x; });",
+                "  var b = a.map(function(x) { return x+1; }).map(function(x$jscomp$1) { return"
+                    + " x$jscomp$1*x$jscomp$1; });",
                 "}")));
   }