Why won't rspec run? Rspec just hangs after starting

Question

Today, I can't run rspec in a project I've tested many times daily for the past year.

It prints the first few startup lines (deprecation warnings and such), and then just hangs. Several minutes pass with no additional output. Ctrl-C successfully kills it with the normal, RSpec is shutting down and will print the summary report... Interrupt again to force quit. message.

I've tried stashing my changes, and changing to the master branch, with no change in the problem. Other projects on my computer continue to run rspec without a problem.

Answer 1

After much head-scratching, I found another zombie instance of rspec still running...perhaps in a terminal that didn't close properly:

% ps -ax | grep rspec
22493 ttys000    0:09.61 /Users/jdoe/myapp/vendor/bundle/ruby/2.6.0/bin/rspec 
11107 ttys001    0:12.40 /Users/jdoe/myapp/vendor/bundle/ruby/2.6.0/bin/rspec 
23059 ttys003    0:00.00 grep rspec

Killing off the old one fixed the problem:

% kill 11107