fix: crash with contenthash

[alexander-akait]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

fixes webpack/webpack#14514

Breaking Changes

No

Additional Info

No

[codecov]

Codecov Report

Merging #869 (c890646) into master (b4be280) will decrease coverage by 0.12%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #869      +/-   ##
==========================================
- Coverage   91.41%   91.28%   -0.13%     
==========================================
  Files           6        6              
  Lines         792      792              
  Branches      214      214              
==========================================
- Hits          724      723       -1     
- Misses         62       63       +1     
  Partials        6        6              

Impacted Files	Coverage Δ
src/index.js	96.15% <ø> (-0.25%)	⬇️

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