Migrator obscures stack trace of unhandled exceptions

[digitalcora]

Trying to set up a Lucky project for the first time, I ran into a strange error that took quite a while to debug. Part of the difficulty was that it turned out Avram was suppressing the real stack trace of the error.

in https://github.com/luckyframework/avram/blob/63be781/src/avram/migrator/migrator.cr:

module Avram::Migrator
  def self.run
    yield
  rescue e : PQ::PQError
    raise e.message.colorize(:red).to_s
  rescue e : Exception   # <=
    raise e.message.to_s # <=
  end
end

The marked lines catch all exceptions and re-raise them, with a stack trace pointing here instead of the original source. The purpose of these lines is unclear to me, and in fact once I deleted them from my project's copy of Avram in lib, I got a much better stack trace that allowed me to solve the problem.

If there would be no harm in doing so, maybe these lines could be removed?

[jwoertink]

Hey @digitalcora Welcome to Lucky! Sorry you ran in to some issues. Hopefully you got it all set now.

That is a good call. Normally when we catch errors like that, it's because we can usually provide a better error message than the one provided by Crystal's default. In this case since we're just re-raising the same error, I'm not seeing any benefit to having it. My guess is that it would be ok to remove those. What are your thoughts @paulcsmith ?

[paulcsmith]

I think the original reason was to highlight the error in red. But if it makes the stacktrace worse then we should remove it :D Thanks for opening the issue @digitalcora!

[matthewmcgarvey]

These are also places I believe are obscuring problems during migrations:

avram/src/avram/migrator/runner.cr

Lines 192 to 193 in 1e6f4ed

	rescue e : Exception
	raise "Unexpected error while running migrations: #{e.message}".colorize(:red).to_s

avram/src/avram/migrator/migration.cr

Lines 99 to 108 in 1e6f4ed

	rescue e : PQ::PQError
	raise <<-ERROR
	There was a problem running this statement:
	#{statements.join("\n")}
	Problem:
	#{e.message}
	ERROR