Files
stream-http/lib/capability.js
T
John Hiesey 4e7103a5a9 Fix feature testing on IE
The previous commit broke IE<=9, since xhr doesn't work cross-domain.
When XDomainRequest is available, use the current page instead of
example.com
2016-10-27 20:03:14 -07:00

41 lines
1.5 KiB
JavaScript

exports.fetch = isFunction(global.fetch) && isFunction(global.ReadableStream)
exports.blobConstructor = false
try {
new Blob([new ArrayBuffer(1)])
exports.blobConstructor = true
} catch (e) {}
var xhr = new global.XMLHttpRequest()
// If XDomainRequest is available (ie only, where xhr might not work
// cross domain), use the page location. Otherwise use example.com
xhr.open('GET', global.XDomainRequest ? '/' : 'https://example.com')
function checkTypeSupport (type) {
try {
xhr.responseType = type
return xhr.responseType === type
} catch (e) {}
return false
}
// For some strange reason, Safari 7.0 reports typeof global.ArrayBuffer === 'object'.
// Safari 7.1 appears to have fixed this bug.
var haveArrayBuffer = typeof global.ArrayBuffer !== 'undefined'
var haveSlice = haveArrayBuffer && isFunction(global.ArrayBuffer.prototype.slice)
exports.arraybuffer = haveArrayBuffer && checkTypeSupport('arraybuffer')
// These next two tests unavoidably show warnings in Chrome. Since fetch will always
// be used if it's available, just return false for these to avoid the warnings.
exports.msstream = !exports.fetch && haveSlice && checkTypeSupport('ms-stream')
exports.mozchunkedarraybuffer = !exports.fetch && haveArrayBuffer &&
checkTypeSupport('moz-chunked-arraybuffer')
exports.overrideMimeType = isFunction(xhr.overrideMimeType)
exports.vbArray = isFunction(global.VBArray)
function isFunction (value) {
return typeof value === 'function'
}
xhr = null // Help gc