only replace `process.env` variable if value is defined

[schiller-manuel]

This fixes https://github.com/goatandsheep/react-native-dotenv/issues/251#issuecomment-1066200376

react-native sets the NODE_ENV after this transformation happens. Code that directly access process.env.NODE_ENV was replaced by babelMode during transformation (if latest babel was used) or by undefined.

With this commit, any access to a process.env variable is only replaced by the corresponding value if its value is set.

[codecov[bot]]

Codecov Report

Base: 98.97% // Head: 98.96% // Decreases project coverage by -0.01% :warning:

Coverage data is based on head (9f3cffd) compared to base (3a940cb). Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #316      +/-   ##
==========================================
- Coverage   98.97%   98.96%   -0.02%     
==========================================
  Files           1        1              
  Lines          98       97       -1     
==========================================
- Hits           97       96       -1     
  Misses          1        1              

Impacted Files	Coverage Δ
index.js	98.96% <100.00%> (-0.02%)	:arrow_down:

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[schiller-manuel]

@goatandsheep can this be merged?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[goatandsheep]

Hi @schiller-manuel let me look into this

[goatandsheep]

I will still need to resolve another issue before I release the next version but I'll merge