Check future completion before setting result in ThrottledCallable

[ccordoba12]

Hey guys, thanks for the great project! We're using some of its utilities and widgets in Spyder and are very pleased with the results.

This fixes a simple InvalidStateError I'm seeing in a feature I'm working on when using the qdebounced decorator.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.90%. Comparing base (a175047) to head (879c08c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #355   +/-   ##
=======================================
  Coverage   84.90%   84.90%           
=======================================
  Files          49       49           
  Lines        3928     3929    +1     
=======================================
+ Hits         3335     3336    +1     
  Misses        593      593           

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[tlambert03]

nice to see you here @ccordoba12, and thanks for the fix. glad to hear you're finding some of the utils here useful for spyder. will cut a new release with this change within the next day or tweo

[ccordoba12]

Thanks @tlambert03!