fetching local file returns a scrambled output

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Hello!

When I try to load a JSON file using file:// protocol content seems to get scrambled 😕

Here's a link to JSON file and below is a snippet which show that parsing with Deno.readTextFile is fine while using fetch output starts at line 4076 out of 4231 (which explains why it can't be parsed)

import { fetch } from "https://deno.land/x/file_fetch/mod.ts"
console.log(Deno.inspect(JSON.parse(await Deno.readTextFile("overworld.gracidea.json")), {depth:1}))
console.log("=======================")
console.log((await fetch(new URL("overworld.gracidea.json", import.meta.url)).then(res => res.text())).substring(0, 200))
console.log("=======================")
console.log(await fetch(new URL("overworld.gracidea.json", import.meta.url)).then(res => res.json()))

PS> deno run --allow-read test.ts
{ pins: [Object], areas: [Array], chunks: [Object] }
=======================
     "id": 215,
      "name": "3-safari-g-se",
      "points": [
        715,
        -1147,
        715,
        -1150,
        719,
        -1152,
        720,
        -1152,
        720,
        -1
=======================
error: Uncaught (in promise) SyntaxError: Unexpected token : in JSON at position 9
console.log(await fetch(new URL("overworld.gracidea.json", import.meta.url)).then(res => res.json()))
            ^
    at JSON.parse (<anonymous>)
    at packageData (deno:op_crates/fetch/22_body.js:247:21)
    at Response.json (deno:op_crates/fetch/22_body.js:192:18)

Any ideas?
Like denoland/deno#2150 (comment) mentioned, this lib is used on deno deploy so it's probably broken on it too

---

Edit: After more digging I think it's from deno's implementation of Response itself that the problem occurs. It is possible actually possible to reconstruct original string using directly TextDecoder and string. Tested both with Deno.iter and iter from std.

const file = await Deno.open(new URL("overworld.gracidea.json", import.meta.url), { read: true })
const original = await Deno.readTextFile("overworld.gracidea.json")
let copy = ""
const body = new ReadableStream<Uint8Array>({
  start: async (controller) => {
    for await (const chunk of Deno.iter(file)) {
      copy += new TextDecoder().decode(chunk)
    }
    file.close();
    controller.close();
  },
  cancel() {
    file.close();
  },
});
console.log((await new Response(body, {status: 200}).text()).substring(0, 200))
console.log(copy === original) //Output "true"
console.log(Deno.inspect(JSON.parse(copy), {depth:1})) //Output "{ pins: [Object], areas: [Array], chunks: [Object] }"