From 76e4a3150f8126e0b952c6129b6e1371afba80c0 Mon Sep 17 00:00:00 2001
From: Maxim Cournoyer <address@hidden>
Date: Thu, 28 Mar 2019 00:26:01 -0400
Subject: [PATCH 4/9] import: pypi: Deduplicate requirements.

* guix/import/pypi.scm (parse-requires.txt): Remove potential duplicates.
---
 guix/import/pypi.scm | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/guix/import/pypi.scm b/guix/import/pypi.scm
index efb5939c78..a90be67bb0 100644
--- a/guix/import/pypi.scm
+++ b/guix/import/pypi.scm
@@ -178,7 +178,11 @@ requirement names."
           ;; (extra) requirements.  Non-optional requirements must appear
           ;; before any section is defined.
           (if (or (eof-object? line) (section-header? line))
-              (reverse result)
+              ;; Duplicates can occur, since the same requirement can be
+              ;; listed multiple times with different conditional markers, e.g.
+              ;; pytest >= 3 ; python_version >= "3.3"
+              ;; pytest < 3 ; python_version < "3.3"
+              (reverse (delete-duplicates result))
               (cond
                ((or (string-null? line) (comment? line))
                 (loop result))
-- 
2.21.0