simpleErr/errors (aka simpler Errors with StackTraces)

github.com/StevenACoffman/simplerr/errors will just work as a drop in replacement to golang.org/x/xerrors, and post-1.13 errors, and provides WithStack as in pkg/errors, but updated for the modern Go world.

Wait, why do I want this?

If you want to add a stacktrace to an error in Go, you might use the pre-Go 1.13 library pkg/errors and it's WithStack.

However, pkg/errors has not been updated since then and has a few compatibility problems with modern Go errors. Also pkg/errors still uses runtime.FuncForPC and emits file paths in the stack trace derived from the raw file name of the source file. This method is outdated, as the on-disk file name of a given package's source may be different from the package path (due to go mod versioning, reproducible build sandboxes, etc). The "modern" equivalent is runtime.CallersFrame, which populates runtime.Frame structs with package path-qualified function names.

Example of simplerr/errors

Checkout this example of usage:

$ cd _example
$ go run -trimpath main.go
Doing something
----
(1) Another bad thing happened: Something went wrong
  -- Stack trace:
  | [...repeated from below...]
Wraps: (2) Another bad thing happened: Something went wrong
Wraps: (3) Something went wrong
  -- Stack trace:main.foo
  | 	command-line-arguments/main.go:22
  | main.bar
  | 	command-line-arguments/main.go:26
  | main.main
  | 	command-line-arguments/main.go:31
  | runtime.main
  | 	runtime/proc.go:225
Wraps: (4) Something went wrong
Error types: (1) *errors.withStack (2) errors.wrapper (3) *errors.withStack (4) main.ErrMyError
  -- Stack trace:main.main
  | 	command-line-arguments/main.go:33

Snazzy output, huh?