Fedora 31 Self-Contained Change proposal: GHC 8.6 and Stackage LTS 13

[Ben Cotton]

https://fedoraproject.org/wiki/Changes/GHC_8.6

== Summary ==
Update Haskell packages from GHC 8.4 to 8.6 and from Stackage LTS 12
to 13 package versions.

== Owner ==
* Name: [[User:Petersen|Jens Petersen]]
* Email: 
* Name: [[Haskell_SIG|Haskell SIG]]
* Email:

== Detailed Description ==
The Haskell ghc compiler will be updated to 8.6.5 (rebase from the
ghc:8.6 module stream) and package version will be updated to current
Stackage LTS 13 versions.  There will also be some packaging
improvements (doc and profiling subpackages).

== Benefit to Fedora ==

Fedora 31 will have the current stable GHC version (8.6.1 was
originally released last Sept),
and packages will be updated to more recent version from the Stackage
LTS 13 set.
The new subpackaging will allow smaller footprint Haskell development
installations without being forced to install docs and profiling
library that take up a lot of space and downloading.

== Scope ==
* Proposal owners:
** rebase ghc to 8.6.5
** update ghc-rpm-macros and cabal-rpm to allows doc and prof subpackaging
** refresh packaging to latest cabal-rpm
** update packages to latest Stackage LTS 13 versions
** build everything in a Koji f31-ghc sidetag repo
** When finished all builds will be pushed by releng to Rawhide before branching

* Other developers: N/A

* Release engineering: [https://pagure.io/releng/issue/8549 #8549]

* Policies and guidelines:
** There may be a minor revision later to update the Haskell Packaging
Guidelines

* Trademark approval: N/A (not needed for this Change)

== Upgrade/compatibility impact ==
Upgrades of Haskell packages should work fine.
Users will then recompile their code with the latest compiler and libraries.

== How To Test ==
* dnf install ghc
* dnf install ghc ghc-doc
* dnf install ghc ghc-prof
* install ghc and cabal-install
* install pandoc, ShellCheck, git-annex
* install ghc-*-devel or ghc-*-prof or ghc-*-doc
* cabal-rpm builddep <favouritepackage>; cabal install <favouritepackage>

== User Experience ==
Users will be happy to have the latest stable major version of GHC and
Haskell packages available to them, and benefit from the improvements
and new compiler features it provides.

== Dependencies ==
Non really: hedgewars rebuild will be tested.

== Contingency Plan ==
* Contingency mechanism: revert and ship the same package versions as F30
* Contingency deadline: Beta freeze
* Blocks release? N/A
* Blocks product? no

== Documentation ==
* https://downloads.haskell.org/~ghc/8.6.5/docs/html/users_guide/8.6.1-notes.h...