fix: resolve #572 — Consider not parsing/stringifying cached transform

src/cache.js

@@ -13,6 +13,7 @@ const path = require("path");
 const zlib = require("zlib");
 const { promisify } = require("util");
 const { readFile, writeFile, mkdir } = require("fs/promises");
+const v8 = require("v8");
 const { sync: findUpSync } = require("find-up");
 const { env } = process;
 const transform = require("./transform");
@@ -50,10 +51,13 @@ const gzip = promisify(zlib.gzip);
  * @param {string} filename
  * @param {boolean} compress
  */
-const read = async function (filename, compress) {
+const read = async function (filename, compress, raw) {
   const data = await readFile(filename + (compress ? ".gz" : ""));
   const content = compress ? await gunzip(data) : data;
 
+  if (raw) {
+    return v8.deserialize(content);
+  }
   return JSON.parse(content.toString());
 };
 
@@ -64,11 +68,16 @@ const read = async function (filename, compress) {
  * @param {boolean} compress
  * @param {any} result
  */
-const write = async function (filename, compress, result) {
-  const content = JSON.stringify(result);
-
-  const data = compress ? await gzip(content) : content;
-  return await writeFile(filename + (compress ? ".gz" : ""), data);
+const write = async function (filename, compress, result, raw) {
+  let data;
+  if (raw) {
+    data = v8.serialize(result);
+  } else {
+    const content = JSON.stringify(result);
+    data = compress ? await gzip(content) : content;
+  }
+  const path = filename + (compress && !raw ? ".gz" : "");
+  return await writeFile(path, data);
 };
 
 /**

src/index.js

@@ -4,6 +4,7 @@
  * @property {string} [cacheDirectory] Directory to store cached files.
  * @property {string} [cacheIdentifier] Unique identifier to bust cache.
  * @property {boolean} [cacheCompression] Whether to compress cached files.
+ * @property {boolean} [cacheRaw] Whether to use raw v8 serialization for cache files.
  * @property {string} [customize] The absolute path of a file that exports a BabelLoaderWrapper.
  * @property {Array<string>} [metadataSubscribers] Names of subscribers registered in the loader context.
  */
@@ -55,6 +56,7 @@ if (/^6\./.test(babel.version)) {
 
 const { version } = require("../package.json");
 const cache = require("./cache");
+const v8 = require("v8");
 const transform = require("./transform");
 const injectCaller = require("./injectCaller");
 const schema = require("./schema.json");

src/schema.json

@@ -20,6 +20,10 @@
       "type": "boolean",
       "default": true
     },
+    "cacheRaw": {
+      "type": "boolean",
+      "default": false
+    },
     "customize": {
       "anyOf": [
         {