feat(loader): add functions support for locals

Author: yungvldai

src/loader.js

@@ -8,6 +8,7 @@ const {
   BASE_URI,
   SINGLE_DOT_PATH_SEGMENT,
   stringifyRequest,
+  stringifyLocals,
 } = require("./utils");
 const schema = require("./loader-options.json");
 
@@ -228,15 +229,14 @@ function pitch(request) {
         ? Object.keys(locals)
             .map(
               (key) =>
-                `\nexport var ${key} = ${JSON.stringify(
-                  /** @type {{[key: string]: string }} */
-                  (locals)[key]
+                `\nexport var ${key} = ${stringifyLocals(
+                  /** @type {{ [key: string]: string }} */ (locals)[key]
                 )};`
             )
             .join("")
         : `\n${
             esModule ? "export default" : "module.exports ="
-          } ${JSON.stringify(locals)};`
+          } ${stringifyLocals(locals)};`
       : esModule
       ? `\nexport {};`
       : "";

src/utils.js

@@ -205,6 +205,17 @@ function getUndoPath(filename, outputPath, enforceRelative) {
     : append;
 }
 
+/**
+ *
+ * @param {*} object
+ * @returns {string}
+ */
+function stringifyLocals(object) {
+  return JSON.stringify(object, (key, value) =>
+    typeof value === "function" ? value.toString() : value
+  );
+}
+
 module.exports = {
   trueFn,
   findModuleById,
@@ -216,5 +227,6 @@ module.exports = {
   BASE_URI,
   SINGLE_DOT_PATH_SEGMENT,
   stringifyRequest,
+  stringifyLocals,
   getUndoPath,
 };