stream: remove isPromise utility function
The function was not checking if the parameter was actually a Promise
instance, but if it has a then
method. Removing the utility function
in favor of a clearer typeof
check, handling the case when the
thenable throws if then method is accessed more than once.
The difference between a thenable and a Promise
may be important when using third party library (the parameter is provided by the user) and/or when Promise.prototype.then
value is changed from userland.
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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