Preemptively error when required ES5 shim/shams are not available #1516
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I was going to say you might check |
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Seems legit, gonna pull this in |
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just sanity check: console.error() is available everywhere console is available, right?
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@petehunt Yes it is, even IE8 has it. While it is possible that some browser does not have it, it will still produce an appropriate error message (console.error not available) and we explicitly mention it next to the shims that the console.*-shim might be necessary. I could do (console.error || console.log) I guess to be on the really safe side, if you prefer (and add appropriate console.* methods to the list).
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@petehunt PS, you probably want to fb.me that link.
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I'll update this to http://fb.me/react-warning-polyfills
Preemptively error when required ES5 shim/shams are not available
As per @andreypopp's idea in #1507, here's an implementation.
I searched through the React code and discovered the list of required shim/shams in the docs is not up-to-date and have updated this PR accordingly (not the docs).
IE8 and really old (but still circulating) versions of most modern browsers are the troublemakers. So basically pretty much every browsers you'll run into has full support, except for a handful of visitors who lack most of them. http://kangax.github.io/compat-table/es5/
In order to keep an ecosystem of reusable components from second-guessing support (and us having to keep forgetting to update the list of required shims), I would recommend extending the list of required shims to include all ES5 shims (not shams): https://github.com/es-shims/es5-shim, it's not that many more and most are really useful.
__DEV__only so didn't bother with size comparison.