Avoid memory issues with hoisted variables

[lukastaegert]

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

List any relevant issue numbers:
Resolves #4181

Description

This will avoid a serious memory issue when using a lot of hoisted variables by changing the way those variables are deoptimized.

[github-actions]

Thank you for your contribution! ❤️

You can try out this pull request locally by installing Rollup via

npm install rollup/rollup#gh-4181-fix-memory-issue

or load it into the REPL:
https://rollupjs.org/repl/?pr=4183

[codecov]

Codecov Report

Merging #4183 (9a81b83) into master (ea96ab0) will increase coverage by 0.00%.
The diff coverage is 91.66%.

@@           Coverage Diff           @@
##           master    #4183   +/-   ##
=======================================
  Coverage   98.33%   98.34%           
=======================================
  Files         202      202           
  Lines        7227     7230    +3     
  Branches     2114     2114           
=======================================
+ Hits         7107     7110    +3     
  Misses         58       58           
  Partials       62       62           

Impacted Files	Coverage Δ
src/ast/variables/LocalVariable.ts	93.24% <87.50%> (+0.18%)	⬆️
src/ast/nodes/Identifier.ts	100.00% <100.00%> (ø)
src/ast/scopes/BlockScope.ts	100.00% <100.00%> (ø)

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[sosukesuzuki]

Thank you!!