From d7f76e34f34352292b696ed3d090e5ec5622d90c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hu=C3=A1ng=20J=C3=B9nli=C3=A0ng?= <i@jhuang.me>
Date: Mon, 21 Oct 2019 11:58:19 -0400
Subject: [PATCH] pass babel.File to helpers.ensure

---
 .../src/tools/build-external-helpers.js       |  2 ++
 .../src/transformation/file/file.js           |  2 +-
 packages/babel-helpers/package.json           |  3 --
 packages/babel-helpers/src/index.js           | 28 ++++++++++++-------
 .../scripts/build-dist.js                     |  1 +
 5 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/packages/babel-core/src/tools/build-external-helpers.js b/packages/babel-core/src/tools/build-external-helpers.js
index c6aa2bf6d21a..6c35dc1bb025 100644
--- a/packages/babel-core/src/tools/build-external-helpers.js
+++ b/packages/babel-core/src/tools/build-external-helpers.js
@@ -2,6 +2,7 @@ import * as helpers from "@babel/helpers";
 import generator from "@babel/generator";
 import template from "@babel/template";
 import * as t from "@babel/types";
+import File from "..";
 
 // Wrapped to avoid wasting time parsing this when almost no-one uses
 // build-external-helpers.
@@ -136,6 +137,7 @@ function buildHelpers(body, namespace, whitelist) {
 
     const ref = (refs[name] = getHelperReference(name));
 
+    helpers.ensure(name, File);
     const { nodes } = helpers.get(name, getHelperReference, ref);
 
     body.push(...nodes);
diff --git a/packages/babel-core/src/transformation/file/file.js b/packages/babel-core/src/transformation/file/file.js
index 1aa6070c73c2..c341d838877b 100644
--- a/packages/babel-core/src/transformation/file/file.js
+++ b/packages/babel-core/src/transformation/file/file.js
@@ -204,7 +204,7 @@ export default class File {
     }
 
     // make sure that the helper exists
-    helpers.ensure(name);
+    helpers.ensure(name, File);
 
     const uid = (this.declarations[name] = this.scope.generateUidIdentifier(
       name,
diff --git a/packages/babel-helpers/package.json b/packages/babel-helpers/package.json
index 44a91b51289a..555a469caa6f 100644
--- a/packages/babel-helpers/package.json
+++ b/packages/babel-helpers/package.json
@@ -17,8 +17,5 @@
   },
   "devDependencies": {
     "@babel/helper-plugin-test-runner": "^7.0.0"
-  },
-  "peerDependencies": {
-    "@babel/core": "^7.0.0-0"
   }
 }
diff --git a/packages/babel-helpers/src/index.js b/packages/babel-helpers/src/index.js
index 643458607384..b7aa97dff1ae 100644
--- a/packages/babel-helpers/src/index.js
+++ b/packages/babel-helpers/src/index.js
@@ -1,4 +1,3 @@
-import { File } from "@babel/core";
 import traverse from "@babel/traverse";
 import * as t from "@babel/types";
 import helpers from "./helpers";
@@ -14,6 +13,7 @@ function makePath(path) {
   return parts.reverse().join(".");
 }
 
+let fileClass = undefined;
 /**
  * Given a file AST for a given helper, get a bunch of metadata about it so that Babel can quickly render
  * the helper is whatever context it is needed in.
@@ -243,13 +243,16 @@ function loadHelper(name) {
     }
 
     const fn = () => {
-      const ast = t.file(helper.ast());
-      return new File(
-        {
-          filename: `babel-helper://${name}`,
-        },
-        { ast },
-      );
+      const file = { ast: t.file(helper.ast()) };
+      if (fileClass) {
+        return new fileClass(
+          {
+            filename: `babel-helper://${name}`,
+          },
+          file,
+        );
+      }
+      return file;
     };
 
     const metadata = getHelperMetadata(fn());
@@ -260,7 +263,7 @@ function loadHelper(name) {
         permuteHelperAST(file, metadata, id, localBindings, getDependency);
 
         return {
-          nodes: file.path.node.body,
+          nodes: file.ast.program.body,
           globals: metadata.globals,
         };
       },
@@ -291,7 +294,12 @@ export function getDependencies(name: string): $ReadOnlyArray<string> {
   return Array.from(loadHelper(name).dependencies.values());
 }
 
-export function ensure(name: string) {
+export function ensure(name: string, newFileClass?) {
+  if (!fileClass) {
+    // optional fileClass used to wrap helper snippets into File instance,
+    // offering `path.hub` support during traversal
+    fileClass = newFileClass;
+  }
   loadHelper(name);
 }
 
diff --git a/packages/babel-plugin-transform-runtime/scripts/build-dist.js b/packages/babel-plugin-transform-runtime/scripts/build-dist.js
index e36ef0c68b0a..214f76b7fbe1 100644
--- a/packages/babel-plugin-transform-runtime/scripts/build-dist.js
+++ b/packages/babel-plugin-transform-runtime/scripts/build-dist.js
@@ -133,6 +133,7 @@ function buildHelper(
 
   if (!esm) {
     bindings = [];
+    helpers.ensure(helperName, babel.File);
     for (const dep of helpers.getDependencies(helperName)) {
       const id = (dependencies[dep] = t.identifier(t.toIdentifier(dep)));
       tree.body.push(template.statement.ast`