Reading UTF16 with BOM from Blob

[jimmywarting]

Version

No response

Platform

Subsystem

No response

What steps will reproduce the bug?

const data = new Uint8Array([
  255, 254,  82, 0, 101, 0, 100, 0,  32, 0,  82, 0,
  111,   0,  99, 0, 107, 0, 115, 0,  32, 0,  40, 0,
   70,   0, 105, 0, 114, 0,  97, 0, 115, 0,  32, 0,
   84,   0,  97, 0, 114, 0, 104, 0, 105, 0, 110, 0,
  105,   0,  32, 0,  82, 0, 101, 0, 109, 0, 105, 0,
  120,   0,  41, 0
])
const type = 'text/plain; charset=utf-16'
const blob = new Blob([data], {type})

blob.text().then(str => {
  console.assert(str.length === 31, 'reading text from utf16 blob should remove BOM')
})

How often does it reproduce? Is there a required condition?

always

What is the expected behavior? Why is that the expected behavior?

Should be 31 character.

What do you see instead?

weird BOM character in the beginning

Additional information

Works in following env:
Firefox: ❌
Chromium : ✅
Safari: ✅
Bun: ✅
Deno: ❌
Node: ❌

I tried doing the same with Response#text they all reported 64 char (includes BOM)

[ankittripathi1]

Can this issue be assigned to me. I'd like to investigate.

[ankittripathi1]

Hi,
I have been digging into this and based on the documentation the function method text() always presumes the the given data will be in utf-8 format. I think this is the root cause of the issue.
I'd still like to investigate it further whether we should expose a way to specify encoding or not.
let me know your thoughts.