Fix nested falsy values being treated as unset

[jeffcasavant]

is_set() correctly returns True for top-level falsy values, but _search_dict() treated falsy values as missing values. Because of this falsy values nested inside dictionaries would cause is_set to return False.

This PR updates _search_dict to behave like the rest of the library does and look for non-None values rather than truey ones.

[codecov[bot]]

Codecov Report

Merging #43 (89a24c8) into master (56f7dfd) will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #43   +/-   ##
=======================================
  Coverage   74.34%   74.34%           
=======================================
  Files           7        7           
  Lines         608      608           
=======================================
  Hits          452      452           
  Misses        156      156           

Impacted Files	Coverage Δ
vyper/vyper.py	82.29% <100.00%> (ø)

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[jeffcasavant]

Yo @alexferl ! What's your take on this coverage loss? I don't think I added anything new & untested; quite the opposite.

[joshkaplinsky]

Any update on this? Looking to use this fix as well! @alexferl

[alexferl]

Thanks, I'll try to release this ASAP.

[jeffcasavant]

Thanks Alex! Glad to help.

[alexferl]

Released in v1.1.1