What is the expected behavior?
Nock should not consider comma-separated query params to match array-based query params
What is the actual behavior?
If nock expects a comma-separated string as a query parameter, and an array-based parameter is set in the tested code, the two params are seen to be equal.
Possible solution
The problem, I believe, happens in matchStringOrRegexp. The interceptor sees the expected value is the comma-separated string (a string), it passes that and the qs.parsed query param (an array) to matchStringOrRegexp. matchStringOrRegexp will typecast the array to a string, meaning they will match:

matchStringOrRegexp([ 'abc', '123' ], 'abc,123') => true

How to reproduce the issue

https://runkit.com/jonogilmour/node-nock-query-issue

Does the bug have a test case?

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