From ad10d4fdef46a00bbe2d95aadc96b9e062fe0539 Mon Sep 17 00:00:00 2001
From: Shea Levy <shea@shealevy.com>
Date: Sat, 29 Oct 2022 07:58:02 -0400
Subject: [PATCH 1/2] lib.modules.doRename: Don't define warning, even as
 undefined, if not warning.

This fixes mkAliasOptionModule in systems with no warning option.
---
 lib/modules.nix | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/modules.nix b/lib/modules.nix
index a7fbec93a2f5..204a2cc1ac12 100644
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -1135,10 +1135,10 @@ rec {
         type = toType;
       });
       config = mkMerge [
-        {
+        (optionalAttrs (options ? warnings) {
           warnings = optional (warn && fromOpt.isDefined)
             "The option `${showOption from}' defined in ${showFiles fromOpt.files} has been renamed to `${showOption to}'.";
-        }
+        })
         (if withPriority
           then mkAliasAndWrapDefsWithPriority (setAttrByPath to) fromOpt
           else mkAliasAndWrapDefinitions (setAttrByPath to) fromOpt)

From 1b6e5ac9520ebcfc283cd18c10856cdcd94c91eb Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Thu, 3 Nov 2022 13:11:04 +0100
Subject: [PATCH 2/2] lib/tests/modules: Test doRename

---
 lib/tests/modules.sh                    |  7 +++++++
 lib/tests/modules/doRename-basic.nix    | 11 +++++++++++
 lib/tests/modules/doRename-warnings.nix | 14 ++++++++++++++
 3 files changed, 32 insertions(+)
 create mode 100644 lib/tests/modules/doRename-basic.nix
 create mode 100644 lib/tests/modules/doRename-warnings.nix

diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index c9ea674ee104..6d2eb24db55c 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -348,6 +348,13 @@ checkConfigOutput 'ok' config.freeformItems.foo.bar ./adhoc-freeformType-survive
 # because of an `extendModules` bug, issue 168767.
 checkConfigOutput '^1$' config.sub.specialisation.value ./extendModules-168767-imports.nix
 
+# doRename works when `warnings` does not exist.
+checkConfigOutput '^1234$' config.c.d.e ./doRename-basic.nix
+# doRename adds a warning.
+checkConfigOutput '^"The option `a\.b. defined in `.*/doRename-warnings\.nix. has been renamed to `c\.d\.e.\."$' \
+  config.result \
+  ./doRename-warnings.nix
+
 cat <<EOF
 ====== module tests ======
 $pass Pass
diff --git a/lib/tests/modules/doRename-basic.nix b/lib/tests/modules/doRename-basic.nix
new file mode 100644
index 000000000000..9d79fa4f26a3
--- /dev/null
+++ b/lib/tests/modules/doRename-basic.nix
@@ -0,0 +1,11 @@
+{ lib, ... }: {
+  imports = [
+    (lib.doRename { from = ["a" "b"]; to = ["c" "d" "e"]; warn = true; use = x: x; visible = true; })
+  ];
+  options = {
+    c.d.e = lib.mkOption {};
+  };
+  config = {
+    a.b = 1234;
+  };
+}
diff --git a/lib/tests/modules/doRename-warnings.nix b/lib/tests/modules/doRename-warnings.nix
new file mode 100644
index 000000000000..6f0f1e87e3aa
--- /dev/null
+++ b/lib/tests/modules/doRename-warnings.nix
@@ -0,0 +1,14 @@
+{ lib, config, ... }: {
+  imports = [
+    (lib.doRename { from = ["a" "b"]; to = ["c" "d" "e"]; warn = true; use = x: x; visible = true; })
+  ];
+  options = {
+    warnings = lib.mkOption { type = lib.types.listOf lib.types.str; };
+    c.d.e = lib.mkOption {};
+    result = lib.mkOption {};
+  };
+  config = {
+    a.b = 1234;
+    result = lib.concatStringsSep "%" config.warnings;
+  };
+}