Subject: Re: [bug#45003] [PATCH] gnu: poetry: Fix a problem with a dependency.

From: Marius Bakke <[email-masked]>
Date: Thu, 03 Dec 2020 22:47:23 +0100

Tanguy Le Carrour <[email-masked]> skriver:

> * gnu/packages/python-xyz.scm (poetry)[arguments]: Relax version constraints
> for python-packaging.

Applied, thanks!

Note: I tried to do this:

diff --git a/gnu/packages/python-xyz.scm b/gnu/packages/python-xyz.scm
index bffb643258..ce4695a956 100644
--- a/gnu/packages/python-xyz.scm
+++ b/gnu/packages/python-xyz.scm
@@ -16003,17 +16003,15 @@ several utilities, as well as an API for building localization tools.")
 (define-public python-packaging
   (package
     (name "python-packaging")
-    (version "20.0")
-    (source
-      (origin
-        (method url-fetch)
-        (uri (pypi-uri "packaging" version))
-        ;; XXX: The URL in the patch file is wrong, it should be
-        ;; <https://github.com/pypa/packaging/pull/256>.
-        (patches (search-patches "python-packaging-test-arch.patch"))
-        (sha256
-         (base32
-          "1y2ip3a4ykkpgnwgn85j6hkspcl0cg3mzms97f40mk57vwqq67gy"))))
+    ;; Note: when updating this, be careful not to change the 'bootstrap'
+    ;; variant below, which can only be updated on 'core-updates'.
+    (version "20.4")
+    (source (origin
+              (method url-fetch)
+              (uri (pypi-uri "packaging" version))
+              (sha256
+               (base32
+                "1y3rc1ams1i25calk6b9jf1gl85ix5a23a146swjvhdr8x7zfms3"))))
     (build-system python-build-system)
     (arguments
      `(#:phases (modify-phases %standard-phases
@@ -16046,25 +16044,26 @@ information.")
 ;; Variants with minimal dependencies, for bootstrapping Pytest.
 (define-public python-packaging-bootstrap
   (hidden-package
-   (package/inherit
-    python-packaging
-    (name "python-packaging-bootstrap")
-    (native-inputs '())
-    (propagated-inputs
-     `(("python-pyparsing" ,python-pyparsing)))
-    (arguments '(#:tests? #f)))))
+   (package
+     (inherit python-packaging)
+     (version "20.0")
+     (source (origin
+               (method url-fetch)
+               (uri (pypi-uri "packaging" version))
+               ;; XXX: The URL in the patch file is wrong, it should be
+               ;; <https://github.com/pypa/packaging/pull/256>.
+               (patches (search-patches "python-packaging-test-arch.patch"))
+               (sha256
+                (base32
+                 "1y2ip3a4ykkpgnwgn85j6hkspcl0cg3mzms97f40mk57vwqq67gy"))))
+     (name "python-packaging-bootstrap")
+     (native-inputs '())
+     (propagated-inputs
+      `(("python-pyparsing" ,python-pyparsing)))
+     (arguments '(#:tests? #f)))))
 
 (define-public python2-packaging-bootstrap
-  (hidden-package
-   (package/inherit
-    python2-packaging
-    (name "python2-packaging-bootstrap")
-    (native-inputs '())
-    (propagated-inputs
-     `(("python-pyparsing" ,python2-pyparsing)))
-    (arguments
-     `(#:tests? #f
-       ,@(package-arguments python2-packaging))))))
+  (package-with-python2 python-packaging-bootstrap))
 
 (define-public python-relatorio
   (package

But the test suite actually picks the 'python-packaging' that is
propagated from 'pytest', and promptly fails.

Updating packaging alone is also a staging-level change, so I did not
dig much further.  But there is some room for improvement here.  Maybe
by (setenv "PYTHONPATH" (string-append ".:" (getenv "PYTHONPATH"))) ?

I also wonder whether pytest needs to propagate packaging at all, or if
wrapping is enough.  Do you know how common it is to "import pytest" or
"from pytest import foo", and whether those code paths would need
'packaging'?

Anyway, future problems!  Thanks for maintaining Poetry.  :-)