Refactor cancellation system to eagerly propagate effective state#958

Merged

njsmith merged 5 commits intopython-trio:masterfrom oremanj:cancelstatus

May 6, 2019

+273-166

Commits on Mar 1, 2019

Commits on Mar 8, 2019

Commits on May 1, 2019

Merge remote-tracking branch 'origin/master' into cancelstatus
oremanj
committed