Bug 1297132

Summary:	RFE: Use the %__erlang_provides macro in the spec file
Product:	[Fedora] Fedora	Reporter:	Randy Barlow <rbarlow>
Component:	erlang	Assignee:	Peter Lemenkov <lemenkov>
Status:	ASSIGNED ---	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	low	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	erlang, jeckersb, jeremy, lemenkov, rhbugs, s
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OS:	Linux
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Description Randy Barlow 2016-01-09 17:21:04 UTC

I noticed that there is a handy %__erlang_provides_requires macro in /usr/lib/rpm/macros.d/macros.erlang and attempted to use it on one of my packages. Unfortunately, this causes my package to depend on lots of Erlang built-ins and the erlang package doesn't mark itself as providing these built-ins. For example, when I use that macro in my erlang-oauth2 package, it fails to install like this:

$ sudo dnf install erlang-oauth2/results/erlang-oauth2-0.6.0-3.fc24.x86_64.rpm
Last metadata expiration check performed 1:57:49 ago on Sat Jan  9 10:17:18 2016.
Error: nothing provides erlang(application:get_env/2) needed by erlang-oauth2-0.6.0-3.fc24.x86_64
(try to add '--allowerasing' to command line to replace conflicting packages)

In the meantime, I can work around this issue by using the correct Requires on my package but it would be a nice improvement if we could get that automatically working, especially since somebody took the time to write that fancy macro.

Comment 1 Peter Lemenkov 2016-02-28 17:32:10 UTC

Initially erlang-rpm-macros was written for a very outdated RPM version (can't remember what was used in 2009), and it contains a lot of ugly workarounds and shortcomings. Fortunately RPM evolved significantly so a lot of these ugly things should just be trashed (which I did already, actually).

I;ve added a lot of fun stuff (automatic dependency picker), so starting from the next erlang-rpm-macros version we should really start using it.

Comment 2 Randy Barlow 2016-03-14 05:13:14 UTC

Hey Peter! I've enjoyed the new automatic dependency system you've developed. I'm happy to close this bug if you are. Thanks!

Comment 3 Peter Lemenkov 2016-03-16 11:24:11 UTC

(In reply to Randy Barlow from comment #2)
> Hey Peter! I've enjoyed the new automatic dependency system you've
> developed. I'm happy to close this bug if you are. Thanks!

We'd better keep it for a while since there is one missing piece - Erlang/OTP itself which doesn't use these macros (yet).