Obtaining a PropEr rebar3

[kostis]

I am opening this issue because I want some help from people who know rebar3 much better than I do.

I was planning to open it even before @ferd's announcement that rebar3 needs an upgrade because I noticed that the following does not work anymore.

For platforms that do not have rebar3 in the path, or even installed (as all my Debian-based machines for example), PropEr's Makefile uses the following code:

REBAR3_URL := https://s3.amazonaws.com/rebar3/rebar3
REBAR3 ?= $(shell which rebar3 || which .$(SEP)rebar3 || \
            (wget --no-check-certificate $(REBAR3_URL) && \
	      chmod +x rebar3 && echo .$(SEP)rebar3))

i.e. it fetches rebar3 from Amazon's repo.

This worked fine until some days ago, when the version of rebar3 in that repo got upgraded to the most recent rebar3 version which has dropped support for Erlang/OTP 21 and prior. This is problematic for e.g. all Debian-based machines which have Erlang/OTP 21 as a package (V10.2.4), but I think that it also means that PropEr users who are still using 20.x will not be able to (re)build PropEr after a make distclean, even though PropEr still supports 20.x and 21.x.

Anyway, here is the question: Is there some way to pull a (secure and correct) rebar3 version from "somewhere else out there" that still supports 21.x and 20.x and use it for all situations (like my machines) that do not have a rebar3 command installed? If so, how?

[ferd]

You can use https://github.com/erlang/rebar3/releases/download/3.15.2/rebar3 -- which is taken straight from the release page at https://github.com/erlang/rebar3/releases/tag/3.15.2 and is the patched up rebar3 compatible down to 19 and up to 23.

However be aware that there is NO compatibility between the code generated Pre-21 and with 24 anymore because the get_stacktrace() bif was removed. That means we can't ship a single rebar3 binary that covers everything anymore just because Erlang/OTP won't make it possible (they never guaranteed it)