bpo-30934: Document coverage details for idlelib tests (#2711)

* Add section to idlelib/idle-test/README.txt.
* Include check that branches are taken both ways.
* Exclude IDLE-specific code that does not run during unit tests.

terryjreedy committed 8y ago

95bebb7264afad88f31f7cdc3b28bacde7c46f93

Parent: 50f5816

Committed by GitHub <noreply@github.com> on 7/16/2017, 4:07:36 AM