From 12f9d8e7303af57ed2d462c17b772c36fd05d0ea Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= <joerg@thalheim.io>
Date: Sat, 8 Oct 2022 10:15:02 +0200
Subject: [PATCH] buildPythonPackage: better error message if no setuptools is
 used.

Before packages did not had to set `format = "other";` if had a custom
installPhase and would not produce a dist folder.
The current error message is hard to understand by new users:

> Executing pythonOutputDistPhase
> mv: cannot stat 'dist': No such file or directory

This commit improves the error message.
---
 .../python/hooks/python-output-dist-hook.sh      | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/interpreters/python/hooks/python-output-dist-hook.sh b/pkgs/development/interpreters/python/hooks/python-output-dist-hook.sh
index e73e45cd597a..83b79d01fa40 100644
--- a/pkgs/development/interpreters/python/hooks/python-output-dist-hook.sh
+++ b/pkgs/development/interpreters/python/hooks/python-output-dist-hook.sh
@@ -3,7 +3,21 @@ echo "Sourcing python-catch-conflicts-hook.sh"
 
 pythonOutputDistPhase() {
     echo "Executing pythonOutputDistPhase"
-    mv "dist" "$dist"
+    if [[ -d dist ]]; then
+        mv "dist" "$dist"
+    else
+        cat >&2 <<EOF
+The build contains no ./dist directory.
+If this project is not setuptools-based, pass
+
+  format = "other";
+
+to buildPythonApplication/buildPythonPackage or another appropriate value as described here:
+
+  https://nixos.org/manual/nixpkgs/stable/#buildpythonpackage-function
+EOF
+        false
+    fi
     echo "Finished executing pythonOutputDistPhase"
 }