[bug#35907] [PATCH] guix import hackage: update list of ghc-included packages

[bug#35907] [PATCH] guix import hackage: update list of ghc-included packages

[Robert Vollmert]

Update the list of excepted dependencies for current ghc-8.4,
based on the release notes at
https://downloads.haskell.org/~ghc/8.4.3/docs/html/users_guide/8.4.3-notes.html

Particularly, this adds `text` to the list, which is a dependency
of `parsec` which was already on the list before, causing build
failures with updated versions of the `text` package.

* guix/import/hackage.scm (ghc-standard-libraries): Update list.
---
 guix/import/hackage.scm | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/guix/import/hackage.scm b/guix/import/hackage.scm
index c97b16197f..bc72f21bf3 100644
--- a/guix/import/hackage.scm
+++ b/guix/import/hackage.scm
@@ -52,34 +52,35 @@
             hackage-package?))
 
 (define ghc-standard-libraries
-  ;; List of libraries distributed with ghc (7.10.2). We include GHC itself as
-  ;; some packages list it.
-  '("array"
+  ;; List of libraries distributed with ghc (8.4.3).
+  ;; https://downloads.haskell.org/~ghc/8.4.3/docs/html/users_guide/8.4.3-notes.html
+  '("ghc"
+    "cabal" ;; in the output of `ghc-pkg list` Cabal is uppercased, but
+            ;; hackage-name->package-name takes this into account.
+    "win32" ;; similarly uppercased
+    "array"
     "base"
-    "bin-package-db"
     "binary"
     "bytestring"
-    "cabal" ;; in the output of `ghc-pkg list` Cabal is uppercased, but
-            ;; hackage-name->package-name takes this into account.
     "containers"
     "deepseq"
     "directory"
     "filepath"
-    "ghc"
+    "ghc-boot"
+    "ghc-compact"
     "ghc-prim"
+    "ghci"
     "haskeline"
-    "hoopl"
     "hpc"
     "integer-gmp"
-    "pretty"
+    "mtl"
+    "parsec"
     "process"
-    "rts"
     "template-haskell"
-    "terminfo"
+    "text"
     "time"
     "transformers"
     "unix"
-    "win32"
     "xhtml"))
 
 (define package-name-prefix "ghc-")
-- 
2.21.0

[bug#35907] note

[Robert Vollmert]

Note that I’m not sure it’s actually a good idea to exclude (all of) these packages
from the dependencies: They’re mostly bundled with ghc because they are used in the
ghc build. As such, it might well be that future ghc versions switch out e.g.
“bytestring” for some alternate data structure, which would then require changes to
all package definitions that currently silently depend on “bytestring”.

Should I include a patch to remove the explicitly packaged `ghc-text` and other
packages of this type?

[bug#35907] note

[Ricardo Wurmus]

Hi Robert,

> Note that I’m not sure it’s actually a good idea to exclude (all of) these packages
> from the dependencies: They’re mostly bundled with ghc because they are used in the
> ghc build. As such, it might well be that future ghc versions switch out e.g.
> “bytestring” for some alternate data structure, which would then require changes to
> all package definitions that currently silently depend on “bytestring”.

While this is correct, we cannot seem to remove them from the
environment when building packages.  If we allow these packages to be
added as inputs and these packages are at different versions from what
GHC provides we get into trouble.

This happened in the past, unfortunately, and it’s hard to debug.

> Should I include a patch to remove the explicitly packaged `ghc-text` and other
> packages of this type?

Yes, I think this would be good.

Thank you for working on this!

--
Ricardo

bug#35907: [PATCH] guix import hackage: update list of ghc-included packages

[Ricardo Wurmus]

Hi Robert,

> Update the list of excepted dependencies for current ghc-8.4,
> based on the release notes at
> https://downloads.haskell.org/~ghc/8.4.3/docs/html/users_guide/8.4.3-notes.html
>
> Particularly, this adds `text` to the list, which is a dependency
> of `parsec` which was already on the list before, causing build
> failures with updated versions of the `text` package.
>
> * guix/import/hackage.scm (ghc-standard-libraries): Update list.

I made a minor change to the commit message (it’s hard to get this
right) and pushed this change to the master branch with commit
1cc12357a6.

Thank you!

--
Ricardo