@std/io: readAllSync only reads a single line from Deno.stdin when stdin is interactive

[frou]

https://jsr.io/@std/io/doc/~/readAllSync

Steps to Reproduce

#!/usr/bin/env deno run

import { readAllSync } from "@std/io"

const content = readAllSync(Deno.stdin)

console.log()
console.log(content.length)

Expected behavior

When running the above script in a shell session, I'd expect to be able to do the following (typing 3 lines then pressing Ctrl-D (i.e. EOF) to finish):

$ ./repro.ts
one
two
three
^D

14
$

That is how all the other languages I've tried work.

Describe the bug

But readAllSync returns after I type the first line.

$ ./repro.ts
one

4
$

Environment

• OS: macOS 12.7.6
• deno version: 2.1.5
• std version: 0.225.0