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Convert var to const/let in src files #22103
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``` npm install -g jscodeshift git clone https://github.com/cpojer/js-codemod.git jscodeshift -t js-codemod/transforms/no-vars.js ./src ```
aminya
commented
Mar 30, 2021
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Description
This converts
vartolet/const.Verification
This conversion is done using jscodeshift developed by Facebook which parses JavaScript down to AST level and performs scope analysis and reference counting to safely replace
varwithconstorlet. This is much safer than converting these by hand which is error-prone.All the tests and CI must pass.
Benefits
Using
varresults in unwanted behavior because its scope is leaked upwards. This PR prevents these kinds of bugs. JsCodeshift already finds the cases where the conversion is not safe andvaris leaked intentionally and leaves them as is.This allows V8 to perform better optimizations for the code
Release Notes
vartolet/constin src folderThis PR supersedes the
varconversion in #22100