@asterite This should fulfill both of our wants. It wont break any existing specs, and if you do want strict comparison, it is available.

I think I would just change the default behaviour of String to strict comparison. One can always use Regex for inclusion. This simplifies the API a bit and shouldn't impact performance a lot (and if it does, well, it's used in the context of specs so super fast performance isn't needed there). The change will probably break all compiler specs which rely on the old behaviour, though, but maybe for now we can change the definition of assert_error "code", "message" to do Regex.new(Regex.escape(message)) inside it.

(That is, I now agree with you about doing an equality check for strings)

Or maybe add assert_error_matches macro?

@asterite I added the strict equality checks and lots of test are failing now. So either:

1. Change all of the string to be absolute matches
2. Replace all string messages with regex
3. Do what @Sija recommended and implement a new macro for stricter string comparison
4. Implement a macro for fuzzy string comparison

I have no problem doing any of the 4 options. Let me know what you prefer.

I like the default of fuzzily matching, I think just having the strict option is best.

in master you can do

expect_raises(MyError) {...}.message.should eq "my message"

Closing in favour of the solution mentioned by @kostya above

@spalladino Should we add that type of example to a doc somewhere so people know how to do a non-fuzzy check?

@samueleaton good catch. I've opened #3909 since Spec::Expectations lacks documentation in most methods.

Just want to mention:

expect_raises(MyError, "") {...}

will pass when block raises MyError with any String message, because of:

"my_string".includes? "" #=> true
"".includes? ""          #=> true

Which is not really expected IMO. Maybe if we had decided to leave check by inclusion, we should have to handle this case differently :

expect_raises(MyError, "") { raise MyError.new("O_o") } # => Expected MyError with "", got #<MyError: O_o>

WDYT ?