Clarify {stream,future}.cancel-{read,write} #593
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dicej
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alexcrichton
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I realized that the current Python CABI definition ignores the case where a first
{stream,future}.cancel-{read,write}blocked and then the component tries cancelling a second time. I think it should simply trap, so this PR adds a newCopyStateto catch this case.(I would have added a test to
test/async/cancel-stream.wast, but it's currently only possible to hit using host powers (because cancellation never blocks in component-to-component cases). Once we add{stream,future}.read-complete, we'll be able to cause{stream,future}.cancel-writeto block from within a pure component WAST, so I added a note to add a test then.)