I have a simple little Flask app and created a suitably simple test script, aimed at making sure I covered much of the executable code. It fires up the app with coverage enabled and hits it with a bunch of requests, then exits. When testing, I have coverage enabled:

CMD="$(which flask) run -h localhost -p $PORT"
if [ "x$DOCOVER" = "xtrue" ] ; then
    coverage run -a $CMD
else
    $CMD
fi

Coverage seems to do the right thing, creating a .coverage file on exit, and when I run the annotate, report, or html commands it does the right thing. Still, it never actually marks any statements within functions as having been executed. Here's coverage from a manual run where I poked the server with three debug endpoints:

> if FLASK_DEBUG:
>     @app.route("/env")
>     def printenv():
!         return jsonify(dict(os.environ))
 
>     @app.route('/api/help')
>     def app_help():
>         """Print available functions."""
!         func_list = {}
!         for rule in app.url_map.iter_rules():
!             if rule.endpoint != 'static':
!                 func_list[rule.rule] = str(app.view_functions[rule.endpoint])
!         return jsonify(func_list)
 
>     @app.get('/shutdown')
>     def shutdown():
!         func = request.environ.get('werkzeug.server.shutdown')
!         if func is None:
!             raise RuntimeError('Not running with the Werkzeug Server')
!         func()
!         return 'Server shutting down...\n'

Clearly, coverage noticed the action which happened during import, but despite the fact that I really did request /env, /api/help, and /shutdown, it never thought any of them were called.

Any idea what I'm missing?

Thx,

Skip Montanaro