Istanbul instrumenter library.
Version 1.1.x now implements instrumentation using
Babel. The implementation is inspired by prior art by @dtinth as demonstrated in the
__coverage__ babel plugin.
It provides 2 “modes” of instrumentation.
The old API that is mostly unchanged (except for incompatibilities noted) and performs the instrumentation using babel as a library.
programVisitor function for the Babel AST that can be used by a Babel plugin to emit instrumentation for ES6 code directly without any source map processing. This is the preferred path for babel users. The Babel plugin is called
Incompatibilities and changes to instrumentation behavior can be found in v0-changes.md.