python3Packages.diceware: fix test failure with python 3.14

Backport upstream fix that sets `prog` explicitly in `ArgumentParser`,
since Python 3.14 changed how the default prog name is derived and
monkeypatching `sys.argv` no longer affects it.

pkgs/development/python-modules/diceware/default.nix

@@ -4,6 +4,7 @@
   fetchPypi,
   setuptools,
   pytestCheckHook,
+  fetchpatch2,
 }:
 
 buildPythonPackage rec {
@@ -16,6 +17,20 @@ buildPythonPackage rec {
     hash = "sha256-VLaQgJ8MVqswhaGOFaDDgE1KDRJ/OK7wtc9fhZ0PZjk=";
   };
 
+  patches = [
+    (fetchpatch2 {
+      # Set prog in ArgumentParser explicitly to fix test failure with Python 3.14
+      # https://github.com/ulif/diceware/issues/122
+      url = "https://github.com/ulif/diceware/commit/77d98606748df7755f36ebbb3bd838b1cdd80c61.patch";
+      includes = [ "diceware/__init__.py" ];
+      hunks = [
+        2
+        3
+      ];
+      hash = "sha256-yXGotV/tq7/vCYhY+1OZgCW3r6/SXTTvsHIU/jywbHc=";
+    })
+  ];
+
   build-system = [ setuptools ];
 
   dependencies = [ setuptools ];