[Codenarc-developer] Inline violations idea

[Artur G. <art...@gm...>]

Hi!

I think I've got an idea for a significant improvement of the (already
great) CodeNarc's test framework and would like to consult it before making
a pull request ;)

The thing that is (for me) the most cumbersome when writing tests is
passing the line number and line text to the assert*Violation[s] methods. I
think I understand the rationale behind having to pass both of them, which
seems to be a kind of a double check / 'checksum'. I'd like to propose an
API in which we only have to write the violation message - and the API
reliably finds the sourceLineText and lineNumber for us. I've made a POC
implementation in
inlineViolations<https://github.com/ArturGajowy/CodeNarc/tree/inlineViolations>
branch
of my fork. The result is best depicted
here<https://github.com/ArturGajowy/CodeNarc/commit/9cb0777e9f1c14d4b532bbd43d0e84bea6ecf494#commitcomment-3147447>
.

As you can see, the whole idea is based on violation markers placed in the
test sources - just in the line the violation takes place. This way, when
we add a line to the source before the violation (e.g. an import we've
missed or a class header, or another violating line) - we don't have to
edit any preexisting violation assertions. There's also no copy'n'paste and
line counting invlolved in the initial process of writing tests :)

The violation markers are removed before the analysis takes place, so that
the assertion errors do not become illegible and the markers don't
interfere with analysis made by rule under test.

As I've said - this is a POC. It lacks: support for multiple violations per
line, standalone tests, a bit of defensive programming and first of all -
your approval of the API :) Let me know what do you think of the idea: do
you like it, would you like this in CodeNarc, are there any issues to
address before you'd like a pull request with that.

And of course - I'll be more than happy to implement the final version :)

Best regards,
Artur Gajowy