babel-plugin-debug-macros
babel-plugin-debug-macros is a Babel plugin that provides build-time debug macros and feature flagging for JavaScript projects. It supports four configuration options: flags, svelte, debugTools, and externalizeHelpers. The flags option allows inlining environment flags and feature flags into consuming modules so that tools like UglifyJS can dead-code-eliminate unreachable branches. Feature flags can be set as booleans or tied to specific versions for deprecation handling. The debugTools option enables macro expansion for warn, assert, and deprecate functions imported from a debug library, with an assertPredicateIndex setting allowing intelligent assertion expansion that avoids costly message generation when assertions would pass. The externalizeHelpers option lets users supply their own runtime implementations, either as a module import or a global namespace reference. The svelte option enables consumers to opt into stripping deprecated code by specifying a package name and minimum version, compiling away dep