Resolves CONFIG_FILE to an absolute path, in place, and returns it.
A relative path is tried against the package root and then the working
directory; the first that exists is written back to process.env. An unset
variable, an absolute path or a package name is left alone. It never
throws, and it is idempotent.
Returns any
the resolved path, the value as given when nothing matched, or
null when CONFIG_FILE is unset
Resolves CONFIG_FILE to an absolute path, in place, and returns it.
A relative path is tried against the package root and then the working directory; the first that exists is written back to process.env. An unset variable, an absolute path or a package name is left alone. It never throws, and it is idempotent.