diff --git a/packages/babel-core/src/helpers/normalize-ast.js b/packages/babel-core/src/helpers/normalize-ast.js
deleted file mode 100644
index d2c91cef91..0000000000
--- a/packages/babel-core/src/helpers/normalize-ast.js
+++ /dev/null
@@ -1,23 +0,0 @@
-import * as t from "babel-types";
-
-/**
- * Normalize an AST.
- *
- * - Wrap `Program` node with a `File` node.
- */
-
-export default function (
-  ast: Object,
-  comments?: Array<Object>,
-  tokens?: Array<Object>,
-) {
-  if (ast) {
-    if (ast.type === "Program") {
-      return t.file(ast, comments || [], tokens || []);
-    } else if (ast.type === "File") {
-      return ast;
-    }
-  }
-
-  throw new Error("Not a valid ast?");
-}
diff --git a/packages/babel-core/src/transformation/pipeline.js b/packages/babel-core/src/transformation/pipeline.js
index 8f0815e6f8..7c2db49cc9 100644
--- a/packages/babel-core/src/transformation/pipeline.js
+++ b/packages/babel-core/src/transformation/pipeline.js
@@ -1,7 +1,7 @@
 /* global BabelFileResult, BabelFileMetadata */
 import fs from "fs";
 
-import normalizeAst from "../helpers/normalize-ast";
+import * as t from "babel-types";
 import File from "./file";
 import OptionManager from "../config/option-manager";
 
@@ -30,7 +30,11 @@ export function transformFromAst(ast: Object, code: string, opts: Object): Babel
   opts = new OptionManager().init(opts);
   if (opts === null) return null;
 
-  ast = normalizeAst(ast);
+  if (ast && ast.type === "Program") {
+    return t.file(ast, [], []);
+  } else if (!ast || ast.type !== "File") {
+    throw new Error("Not a valid ast?");
+  }
 
   const file = new File(opts);
   return file.wrap(code, function () {