From 55ee7ab4a6b5281cf1c352bc714b07c59c4546ee Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Thu, 10 Mar 2022 20:25:49 +0100
Subject: lib.types.optionType: Only merge when necessary

---
 lib/tests/modules.sh                                       |  3 +++
 .../modules/adhoc-freeformType-survives-type-merge.nix     | 14 ++++++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 lib/tests/modules/adhoc-freeformType-survives-type-merge.nix

(limited to 'lib/tests')

diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index e4bb7ad21900f..350fe85e7487f 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -311,6 +311,9 @@ checkConfigOutput '^"hello"$' config.theOption.str ./optionTypeMerging.nix
 # Test that types.optionType correctly annotates option locations
 checkConfigError 'The option .theOption.nested. in .other.nix. is already declared in .optionTypeFile.nix.' config.theOption.nested ./optionTypeFile.nix
 
+# Test that types.optionType leaves types untouched as long as they don't need to be merged
+checkConfigOutput 'ok' config.freeformItems.foo.bar ./adhoc-freeformType-survives-type-merge.nix
+
 cat <<EOF
 ====== module tests ======
 $pass Pass
diff --git a/lib/tests/modules/adhoc-freeformType-survives-type-merge.nix b/lib/tests/modules/adhoc-freeformType-survives-type-merge.nix
new file mode 100644
index 0000000000000..3cefb543c256b
--- /dev/null
+++ b/lib/tests/modules/adhoc-freeformType-survives-type-merge.nix
@@ -0,0 +1,14 @@
+{ lib, ... }: {
+  options.dummy = lib.mkOption { type = lib.types.anything; default = {}; };
+  freeformType =
+    let
+      a = lib.types.attrsOf (lib.types.submodule { options.bar = lib.mkOption { }; });
+    in
+    # modifying types like this breaks type merging.
+    # This test makes sure that type merging is not performed when only a single declaration exists.
+    # Don't modify types in practice!
+    a // {
+      merge = loc: defs: { freeformItems = a.merge loc defs; };
+    };
+  config.foo.bar = "ok";
+}
-- 
cgit 1.4.1