feat: async callback for modifying JSON

Author: zardoy

package.json

@@ -22,7 +22,7 @@
     "build"
   ],
   "scripts": {
-    "prepublishOnly": "yarn test && tsc",
+    "prepublishOnly": "tsc && yarn test",
     "test": "ava --serial"
   },
   "devDependencies": {
@@ -44,7 +44,7 @@
     "detect-indent": "^6.1.0",
     "graceful-fs": "^4.2.6",
     "parse-json": "^5.2.0",
-    "strip-bom": "^5.0.0",
+    "strip-bom": "4",
     "type-fest": "^1.2.0"
   },
   "ava": {

src/index.ts

@@ -4,6 +4,8 @@ import stripBom from "strip-bom"
 import parseJson from "parse-json"
 import fs from "graceful-fs"
 
+type MaybePromise<T> = T | Promise<T>;
+
 interface Options {
     /** @default utf-8 */
     encoding: BufferEncoding
@@ -38,13 +40,13 @@ type GettersDeep<T extends object> = {
 
 export type ModifyJsonFileFunction<T extends object> = (
     path: string,
-    modifyFields: Partial<T | GettersDeep<T>> | ((oldJson: T) => T), 
+    modifyFields: Partial<T | GettersDeep<T>> | ((oldJson: T) => MaybePromise<T>), 
     options?: Options
 ) => Promise<void>;
 
 type ModifyJsonFileGenericFunction = <T extends object>(
     path: string,
-    modifyFields: Partial<T | GettersDeep<T>> | ((oldJson: T) => T), 
+    modifyFields: Partial<T | GettersDeep<T>> | ((oldJson: T) => MaybePromise<T>), 
     options?: Partial<Options>
 ) => Promise<void>;
 
@@ -90,7 +92,7 @@ export const modifyJsonFile: ModifyJsonFileGenericFunction = async (
         // todo remove restriction or not?
         if (!json || typeof json !== "object" || Array.isArray(json)) throw new TypeError(`${path}: JSON root type must be object`);
         if (typeof modifyFields === "function") {
-            json = modifyFields(json)
+            json = await modifyFields(json)
         } else {
             for (const [name, value] of Object.entries(modifyFields)) {
                 if (!(name in json)) {

tests/index.test.ts

@@ -4,7 +4,7 @@ import jsonfile from "jsonfile";
 import path from "path";
 import del from "del";
 import nanoid from "nanoid";
-import { modifyJsonFile } from "../src/index"
+import { modifyJsonFile, modifyPackageJsonFile } from "../build/"
 import fs from "fs/promises";
 
 const jsonFilePath = path.join(__dirname, "testing-file.json");
@@ -35,4 +35,12 @@ test("modifies JSON file", async t => {
     })
     const modifiedJsonFle = await fs.readFile(jsonFilePath, "utf8");
     t.snapshot(modifiedJsonFle);
+})
+
+test("modifies package.json file with async function", async t => {
+    await modifyPackageJsonFile(jsonFilePath, async ({ main }) => {
+        return { types: main, name: "ahaha" };
+    })
+    const modifiedJsonFle = await fs.readFile(jsonFilePath, "utf8");
+    t.snapshot(modifiedJsonFle);
 })

tests/snapshots/index.test.ts.md

@@ -16,3 +16,12 @@ Generated by [AVA](https://avajs.dev).
             "type-fest": "^1.0.0"␊
         }␊
     }`
+
+## modifies package.json file with async function
+
+> Snapshot 1
+
+    `{␊
+        "types": "index.js",␊
+        "name": "ahaha"␊
+    }`

tests/snapshots/index.test.ts.snap

@@ -1811,20 +1811,15 @@ strip-ansi@^6.0.0:
   dependencies:
     ansi-regex "^5.0.0"
 
-strip-bom@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-3.0.0.tgz#2334c18e9c759f7bdd56fdef7e9ae3d588e68ed3"
-  integrity sha1-IzTBjpx1n3vdVv3vfprj1YjmjtM=
-
-strip-bom@^4.0.0:
+strip-bom@4, strip-bom@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-4.0.0.tgz#9c3505c1db45bcedca3d9cf7a16f5c5aa3901878"
   integrity sha512-3xurFv5tEgii33Zi8Jtp55wEIILR9eh34FAW00PZf+JnSsTmV/ioewSgQl97JHvgjoRGwPShsWm+IdrxB35d0w==
 
-strip-bom@^5.0.0:
-  version "5.0.0"
-  resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-5.0.0.tgz#88d2e135d154dca7a5e06b4a4ba9653b6bdc0dd2"
-  integrity sha512-p+byADHF7SzEcVnLvc/r3uognM1hUhObuHXxJcgLCfD194XAkaLbjq3Wzb0N5G2tgIjH0dgT708Z51QxMeu60A==
+strip-bom@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-3.0.0.tgz#2334c18e9c759f7bdd56fdef7e9ae3d588e68ed3"
+  integrity sha1-IzTBjpx1n3vdVv3vfprj1YjmjtM=
 
 strip-json-comments@~2.0.1:
   version "2.0.1"