Implement a new utility module for injecting module imports.

packages/babel-helper-module-transforms/src/index.js

@@ -3,6 +3,8 @@ import * as t from "babel-types";
 import template from "babel-template";
 import chunk from "lodash/chunk";
 
+import { isModule } from "babel-helper-module-imports";
+
 import rewriteThis from "./rewrite-this";
 import rewriteLiveReferences from "./rewrite-live-references";
 import normalizeAndLoadModuleMetadata, {
@@ -10,32 +12,7 @@ import normalizeAndLoadModuleMetadata, {
   isSideEffectImport,
 } from "./normalize-and-load-metadata";
 
-export { hasExports, isSideEffectImport };
-
-export function isModule(path: NodePath, requireUnambiguous: boolean = false) {
-  const { sourceType } = path.node;
-  if (sourceType !== "module" && sourceType !== "script") {
-    throw path.buildCodeFrameError(
-      `Unknown sourceType "${sourceType}", cannot transform.`,
-    );
-  }
-
-  const filename = path.hub.file.opts.filename;
-  if (/\.mjs$/.test(filename)) {
-    requireUnambiguous = false;
-  }
-
-  return (
-    path.node.sourceType === "module" &&
-    (!requireUnambiguous || isUnambiguousModule(path))
-  );
-}
-
-// This approach is not ideal. It is here to preserve compatibility for now,
-// but really this should just return true or be deleted.
-function isUnambiguousModule(path) {
-  return path.get("body").some(p => p.isModuleDeclaration());
-}
+export { hasExports, isSideEffectImport, isModule };
 
 /**
  * Perform all of the generic ES6 module rewriting needed to handle initial