Fails to parse query containing `%2B` ( urlencoded `+` ) when query mark as array of date/string.

[drsmile1001]

What version of Elysia is running?

1.2.25

What platform is your computer?

No response

What steps can reproduce the bug?

import { Elysia, t } from "elysia";

const app = new Elysia().get(
  "/",
  ({ query }) => {
    return query;
  },
  {
    query: t.Object({
      date: t.Array(t.Date()), // Array here!
    }),
  }
);

const url = new URL("http://localhost/");
url.searchParams.append("date", "2025-01-01T01:00:00+08:00");

const result = await app
  .handle(new Request(url.toString()))
  .then((res) => res.json());

console.log(result);

What is the expected behavior?

The array of date should be parsed correctly and the result should be:

{
  date: [ new Date("2025-01-01T01:00:00+08:00") ]
}

What do you see instead?

The array of date is not parsed correctly and the result is:

{
  type: "validation",
  on: "query",
  summary: "Property 'date' should be one of: 'ArrayString', 'array'",
  property: "/date",
  message: "Expected union value",
  expected: {},
  found: {
    date: [ "2025-01-01T01:00:00 08:00" ], // notice the missing '+' sign
  },
}

Additional information

I looked into issues related to encoding +, including:

• Do not handle encoded space as "+" in query string correct? #821 Fixed!
• Params do not encode %20 to + or space #924 It seems not a bug, but not answered yet.
• Broken query params handling behavier on escaped character "%2B" (the "+" symbol) in 1.1.26 #943 I think it was fixed after 1.2.15 to now (1.2.25).
• bug: URL encoded '+' character gets replaced after decoding in query values #1001 Like Broken query params handling behavier on escaped character "%2B" (the "+" symbol) in 1.1.26 #943, I think it was fixed after 1.2.15 to now (1.2.25).

I also saw an explanation of the behavior of URLSearchParams: #960 (comment).
I also believe following this behavior is correct. Therefore, the example code above generates the query string using URLSearchParams.

However, it seems that the Elysia parsing middleware still has some issues when dealing with arrays. If not wrapped in an array, the current behavior is correct.

Edited, give a sample to show current issue is about array of string has problem.

import Elysia, { t } from "elysia";

const api = new Elysia().get("", ({ query }) => query, {
  query: t.Object({
    array: t.Array(t.String()), // Mark as an array
    simple: t.String(), // Mark as not an array
  }),
});

const url = new URL("http://localhost/");
url.searchParams.append("array", "a+b");
url.searchParams.append("array", "c+d");
url.searchParams.append("simple", "e+f");
console.log(url.href); //http://localhost/?array=a%2Bb&array=c%2Bd&simple=e%2Bf  `+` encoded as `%2B`

const result = await api
  .handle(new Request(url.href))
  .then((response) => response.json());

console.log(result);

/**
  * Result:
  {
    array: [ "a b", "c d" ], // missing `+` in the array
    simple: "e+f", // correct when not an array
  }
 */

Have you try removing the node_modules and bun.lockb and try again yet?

No response

[SystemVll]

Hello @drsmile1001,

after a little investigation it sounds like arrays of t.Date() doesn't seem to work with query params, a temporary solution would be to replace with array of t.String()

import { Elysia, t } from "elysia";

const app = new Elysia().get(
	"/",
	({ query }) => {
		return query;
	},
	{
		query: t.Object({
			date: t.Array(t.String()), // String here!
		}),
	}
);

console.log(new Date());

const url = new URL("http://localhost/");
url.searchParams.append(
	"date",
	"2025-04-13T18:50:27.822Z 2025-04-13T18:50:27.822Z"
);

const result = await app
	.handle(new Request(url.toString()))
	.then((res) => res.json());

console.log(result);

[drsmile1001]

Hello @Inplex-sys

No, the current issue is that %2B or the URL-encoded + is incorrectly interpreted as a space when marked as an array in the query.

import Elysia, { t } from "elysia";

const api = new Elysia().get("", ({ query }) => query, {
  query: t.Object({
    array: t.Array(t.String()), // Mark as an array
    simple: t.String(), // Mark as not an array
  }),
});

const url = new URL("http://localhost/");
url.searchParams.append("array", "a+b");
url.searchParams.append("array", "c+d");
url.searchParams.append("simple", "e+f");
console.log(url.href); //http://localhost/?array=a%2Bb&array=c%2Bd&simple=e%2Bf  `+` encoded as `%2B`

const result = await api
  .handle(new Request(url.href))
  .then((response) => response.json());

console.log(result);

/**
  * Result:
  {
    array: [ "a b", "c d" ], // missing `+` in the array
    simple: "e+f", // correct when not an array
  }
 */

[SystemVll]

Okay, got it, i'll work on it and make a pull request