feat: return blob if content-type isn't text, svg, xml or json

[danielroe]

resolves #38

For binary content types, $fetch will instead return a Blob object.

You can optionally specify blob, arrayBuffer or text to force parsing the body with the respective FetchResponse method.

// Use JSON.parse
await $fetch('/movie?lang=en', { parseResponse: JSON.parse })

// Return text as is
await $fetch('/movie?lang=en', { parseResponse: txt => txt })

// Get the blob version of the response
await $fetch('/api/generate-image', { responseType: 'blob' })

Typing

$fetch('api') // Promise<any>
$fetch<boolean>('api') // Promise<boolean>
$fetch<boolean>('api', { responseType: 'text' }) // Type '"text"' is not assignable to type '"json" | undefined'.ts(2322)
$fetch('api', { responseType: 'json' }) // Promise<any>
$fetch<boolean>('api', { responseType: 'json' }) // Promise<boolean>
$fetch('api', { responseType: 'text' }) // Promise<string>
$fetch('api', { responseType: 'arrayBuffer' }) // Promise<ArrayBuffer>
$fetch('api', { responseType: 'blob' }) // Promise<Blob>

[pi0]

I would make a type for return type to reuse with ResponseType