Using Pretender with fetch.
#60
Comments
|
I'm down for it. I'd like to extend and generalize pretender to mock out several browser APIs that might seem unrelated but have to be controlled for isolated tests: xhr, fetech, geolocation, etc. |
|
The polyfil for fetch does use xhr https://github.com/github/fetch/blob/master/fetch.js#L263 So that buys us time until someday where native fetch can be used cross platform |
|
Also the ember wrapper never falls back to native fetch |
|
I tried to use pretender with fetch, but as FF and Chrome now ship fetch, this isn't working for now. |
|
If you use ember-fetch it will always use the polyfil (for better or worse) |
|
Oh, thx, I'll consider it :) |
|
I'd happily accept a PR, I just don't have a need for fetch myself right now so that work should be handled by a more vested party. |
|
This feels really dirty, but, to force whatwg-fetch to apply in Chrome, I did the following in the HTML I run my tests against: |
|
This looks interesting https://github.com/sstur/fetch-pretender |
xg-wang
pushed a commit
to xg-wang/pretender
that referenced
this issue
May 23, 2018
tl;dr - This commit add support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender will "just work". Per Yetch homepage, the supplement set of yetch impl and spec include: - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. For `fake_xml_http_request` impl, the request is resolved once its state is changed to `DONE` so the `reject` is not cathed. So the senario happens in pretender is: 1. state chagne to `DONE`, trigger resolve request 2. abort, trigger reject 3. xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.
xg-wang
pushed a commit
to xg-wang/pretender
that referenced
this issue
May 23, 2018
tl;dr - This commit add support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Motivation ------ Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the senario happens in pretender is: 1). state chagne to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.
xg-wang
pushed a commit
to xg-wang/pretender
that referenced
this issue
May 23, 2018
tl;dr - This commit adds support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Motivation ------ Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the senario happens in pretender is: 1). state changes to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.
xg-wang
pushed a commit
to xg-wang/pretender
that referenced
this issue
May 23, 2018
tl;dr - This commit adds support for fetch, fix pretenderjs#60. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the scenario happens in pretender is: 1). state changes to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.
Merged
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
It would be nice to be able to use
fetchinstead ofXMLHttpRequest. When using the non-nativefetchpolyfil Pretender would likely still work (because the polyfill usesXMLHttpRequestto implementfetch), but it doesn't seem that native fetch requests would be handled by Pretender.Spec: https://fetch.spec.whatwg.org
This issue is mostly to lay out a path forward.
/cc @cowboyd @toranb
The text was updated successfully, but these errors were encountered: