fix(types): handle union types in generic parameter

[jh-leong]

close #2785

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commit: da3a894

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.11%. Comparing base (2974e20) to head (da3a894).
Report is 1 commits behind head on v2.

Additional details and impacted files

@@            Coverage Diff             @@
##               v2    #2794      +/-   ##
==========================================
+ Coverage   89.66%   90.11%   +0.44%     
==========================================
  Files          14       14              
  Lines        1335     1335              
  Branches      219      221       +2     
==========================================
+ Hits         1197     1203       +6     
+ Misses        137      131       -6     
  Partials        1        1              

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[posva]

Why does this fix the problem? Isn't x extends unknown always true? I want to add a note comment for my future self and other contributors
TS is sometimes so weird 🫠

[jh-leong]

When conditional types act on a generic type, they become distributive when given a union type (Distributive Conditional Types).

In this case, it will always resolve to the first branch because unknown is the top type in TypeScript.

[posva]

Thanks! This makes me wonder if there isn't another bug up the chain of types. But this is already good enough!

[posva]

Thanks a lot!

[posva]

Thanks! This makes me wonder if there isn't another bug up the chain of types. But this is already good enough!