support Ruby 2.4's frozen string literals (1.4.x branch)

[flavorjones]

Note this change is made relative to the 1-4-stable branch.

It would be great to cut an updated 1.4.x release after merging this in.

[flavorjones]

Note that you can test before/after by setting RUBYOPT="--enable-frozen-string-literal --debug=frozen-string-literal"

[drbrain]

Will an eval test work?

[flavorjones]

@drbrain Not sure what you mean?

[drbrain]

A test like:

parser_output = Racc.generate_a_parser "grammar"

eval "# frozen_string_literal: true\n#{parser_output}"

Parser.parse "something"

assert true, "Parser didn't raise a frozen string exception, 🎊"

[flavorjones]

Ah, I see what you're getting at.

For the 1.4 branch, this changeset was small, but check out what had to be done for master: #81

So I'd personally prefer to see the entire test suite run with the frozen strings option; unfortunately the travis setup is outdated and has been failing for some time. I'll add a commit fixing it up, and you can be the judge.

[drbrain]

👍🏻

[pat]

I realise this PR has been dormant for quite some time. Would love to get frozen string literal support in though!

With regards to getting things on Travis green: I've just done some poking around, and added the following to try to get the tests running. They're actually running on 1.9 (albeit with some failures), but no luck elsewhere (due to minitest/autorun not being available for some reason): flavorjones/racc@flavorjones-1.4-frozen-string-literal...pat:flavorjones-1.4-frozen-string-literal - the results can be found at https://travis-ci.org/pat/racc - any thoughts on next steps are very welcome :)

[hsbt]

@flavorjones Can you rebase with the current 1-4-stable branch?

[flavorjones]

Rebased and pushed! Please take a look at my edit to the github actions, I'm not 100% sure what I'm doing there.

[flavorjones]

Re-pushed with an updated change to lib/racc/parserfilegenerator.rb to address frozen string test failures.

[flavorjones]

OK - I'm not sure why the Actions aren't passing, this is green on my local machine. Can I request a second pair of eyes on this?

[flavorjones]

@hsbt - can you help me understand why this was closed without merging? I rebased as you requested and tests were green.

[hsbt]

@flavorjones Ah, I renamed 1-4-stable to master branch. Can you submit this pull-request from master branch again?

[flavorjones]

@hsbt resubmitted as #127 rebased on master