instrument

Instruments the vars named by sym-or-syms, a symbol or collection of symbols, or all instrumentable vars if sym-or-syms is not specified. If a symbol identifies a namespace then all symbols in that namespace will be enumerated. If a var has an :args fn-spec, sets the var's root binding to a fn that checks arg conformance (throwing an exception on failure) before delegating to the original fn. The opts map can be used to override registered specs, and/or to replace fn implementations entirely. Opts for symbols not included in sym-or-syms are ignored. This facilitates sharing a common options map across many different calls to instrument. The opts map may have the following keys: :spec a map from var-name symbols to override specs :stub a set of var-name symbols to be replaced by stubs :gen a map from spec names to generator overrides :replace a map from var-name symbols to replacement fns :spec overrides registered fn-specs with specs your provide. Use :spec overrides to provide specs for libraries that do not have them, or to constrain your own use of a fn to a subset of its spec'ed contract. :stub replaces a fn with a stub that checks :args, then uses the :ret spec to generate a return value. :gen overrides are used only for :stub generation. :replace replaces a fn with a fn that checks args conformance, then invokes the fn you provide, enabling arbitrary stubbing and mocking. :spec can be used in combination with :stub or :replace. Returns a collection of syms naming the vars instrumented.