From b112b109afbba8cab9d0b1a513160453d26ac913 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9=20Schr=C3=B6der?= <andre.schroeder@andresco.de>
Date: Fri, 10 Jul 2026 19:13:23 +0200
Subject: [PATCH] python3Packages.icalendar: fix build failure for python3.12

Error message:

```
Executing pythonRuntimeDepsCheck
Checking runtime dependencies for icalendar-7.2.0-py3-none-any.whl
  - typing-extensions not installed
```

MWE flake.nix:

```
{
  inputs.nixpkgs.url = "github:NixOS/nixpkgs/0bb7ec54c8483066ec9d7720e780a5caa71f8612";

  outputs = { nixpkgs, ... }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };
    in {
      packages.${system} = {
        python312 = pkgs.python312Packages.icalendar;
        python312-fixed = pkgs.python312Packages.icalendar.overridePythonAttrs (old: {
          dependencies = old.dependencies ++ [ pkgs.python312Packages.typing-extensions ];
        });
        python313 = pkgs.python313Packages.icalendar;
        python314 = pkgs.python314Packages.icalendar;
      };
    };
}
```

Build it:

```
for package in python312 python312-fixed python313 python314; do
  if nix build --no-link ".#$package" >/dev/null 2>&1; then
    echo "$package: success"
  else
    echo "$package: failure"
  fi
done
```

Which prints:

```
python312: failure
python312-fixed: success
python313: success
python314: success
```
---
 pkgs/development/python-modules/icalendar/default.nix | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pkgs/development/python-modules/icalendar/default.nix b/pkgs/development/python-modules/icalendar/default.nix
index 88bb69201ea5..09d7eedadbad 100644
--- a/pkgs/development/python-modules/icalendar/default.nix
+++ b/pkgs/development/python-modules/icalendar/default.nix
@@ -3,9 +3,11 @@
   buildPythonPackage,
   fetchFromGitHub,
   replaceVars,
+  pythonOlder,
   hatch-vcs,
   hatchling,
   python-dateutil,
+  typing-extensions,
   tzdata,
   hypothesis,
   pyprojectVersionPatchHook,
@@ -36,6 +38,10 @@ buildPythonPackage rec {
   dependencies = [
     python-dateutil
     tzdata
+  ]
+  ++ lib.optionals (pythonOlder "3.13") [
+    # typing.TypeIs arrived in Python 3.13.
+    typing-extensions
   ];
 
   nativeCheckInputs = [