Use new blob read methods

[jimmywarting]

file-type/browser.js

Lines 23 to 45 in 7021d9a

	function convertBlobToBuffer(blob) {
	return new Promise((resolve, reject) => {
	const fileReader = new FileReader();
	fileReader.addEventListener('loadend', event => {
	let data = event.target.result;
	if (data instanceof ArrayBuffer) {
	data = toBuffer(new Uint8Array(event.target.result));
	}
	resolve(data);
	});
	fileReader.addEventListener('error', event => {
	reject(new Error(event.message));
	});
	fileReader.addEventListener('abort', event => {
	reject(new Error(event.type));
	});
	fileReader.readAsArrayBuffer(blob);
	});
	}

To support Blob's in node v15.7 you need to start using the new blob read methods instead

- const toBuffer = require('typedarray-to-buffer');

async function fromBlob(blob) {
- const buffer = await convertBlobToBuffer(blob)
+ const buffer = await blob.arrayBuffer().then(Buffer.from)
  return core.fromBuffer(buffer)
}

- /**
- Convert Web API File to Node Buffer.
- @param {Blob} blob - Web API Blob.
- @returns {Promise<Buffer>}
- */
- function convertBlobToBuffer(blob) {
- 	return new Promise((resolve, reject) => {
- 		const fileReader = new FileReader();
- 		fileReader.addEventListener('loadend', event => {
- 			let data = event.target.result;
- 			if (data instanceof ArrayBuffer) {
- 				data = toBuffer(new Uint8Array(event.target.result));
- 			}
- 
- 			resolve(data);
- 		});
- 
- 		fileReader.addEventListener('error', event => {
- 			reject(new Error(event.message));
- 		});
- 
- 		fileReader.addEventListener('abort', event => {
- 			reject(new Error(event.type));
- 		});
- 
- 		fileReader.readAsArrayBuffer(blob);
- 	});
- }

[jimmywarting]

You could also safely remove typedarray-to-buffer dep

[sindresorhus]

We can keep this open so we don't forget. We cannot do this until we target Node.js 16 though.

[jimmywarting]

I realised this was a dupe of my own #437