[optimize] Form Data builder supports Array fields

package.json

@@ -1,6 +1,6 @@
 {
     "name": "koajax",
-    "version": "0.9.2",
+    "version": "0.9.3",
     "license": "LGPL-3.0",
     "author": "[email protected]",
     "description": "HTTP Client based on Koa-like middlewares",
@@ -36,7 +36,7 @@
     "devDependencies": {
         "@parcel/packager-ts": "~2.9.3",
         "@parcel/transformer-typescript-types": "~2.9.3",
-        "@types/core-js": "^2.5.5",
+        "@types/core-js": "^2.5.6",
         "@types/jest": "^29.5.4",
         "@types/jsdom": "^21.1.2",
         "@types/node": "^18.17.14",
@@ -51,7 +51,7 @@
         "parcel": "~2.9.3",
         "prettier": "^3.0.3",
         "ts-jest": "^29.1.1",
-        "typedoc": "^0.25.0",
+        "typedoc": "^0.25.1",
         "typedoc-plugin-mdn-links": "^3.1.0",
         "typescript": "~5.2.2"
     },

source/utility.ts

@@ -1,5 +1,5 @@
 import { Observable } from 'iterable-observer';
-import { isTypedArray, stringifyDOM, formToJSON } from 'web-utility';
+import { likeArray, isTypedArray, stringifyDOM, formToJSON } from 'web-utility';
 
 export async function parseDocument(text: string, contentType = '') {
     const [type] = contentType?.split(';') || [];
@@ -13,8 +13,13 @@ export async function parseDocument(text: string, contentType = '') {
 export function makeFormData(data: Record<string, any>) {
     const formData = new FormData();
 
-    for (const [key, value] of Object.entries(data))
-        formData.append(key, value);
+    for (const [key, value] of Object.entries(data)) {
+        const list = (
+            typeof value !== 'string' && likeArray(value) ? value : [value]
+        ) as ArrayLike<string | Blob>;
+
+        Array.from(list, item => formData.append(key, item));
+    }
 
     return formData;
 }

test/utility.spec.ts

@@ -1,6 +1,7 @@
 import 'core-js/es/object/from-entries';
 import 'core-js/es/string/match-all';
-import { parseHeaders, serializeNode } from '../source';
+
+import { makeFormData, parseHeaders, serializeNode } from '../source';
 
 describe('HTTP utility', () => {
     describe('Parse Headers', () => {
@@ -30,6 +31,28 @@ describe('HTTP utility', () => {
         });
     });
 
+    describe('Form Data', () => {
+        it('should make a Form Data instance from a Plain Object', () => {
+            const formData = makeFormData({
+                a: 1,
+                b: [2, 3],
+                c: new Blob()
+            });
+            const entries = [...formData.entries()];
+
+            expect(entries.filter(([key]) => key === 'a')).toEqual([
+                ['a', '1']
+            ]);
+            expect(entries.filter(([key]) => key === 'b')).toEqual([
+                ['b', '2'],
+                ['b', '3']
+            ]);
+            expect(entries.find(([key]) => key === 'c')?.[1]).toBeInstanceOf(
+                Blob
+            );
+        });
+    });
+
     describe('Serialize DOM nodes', () => {
         it('should serialize Input fields to String', () => {
             document.body.innerHTML = `