lib/modules: Report a good error when option tree has bare type

Note that this removes the possibility of declaring an option
named `_type`.

4 files changed, 21 insertions, 0 deletions

diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index b933a24a57a12..5f2e3f2a31144 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -393,6 +393,11 @@ checkConfigError \
   config.set \
   ./declare-set.nix ./declare-enable-nested.nix
 
+# Options: accidental use of an option-type instead of option (or other tagged type; unlikely)
+checkConfigError 'Expected an option declaration at option path .result. but got an attribute set with type option-type' config.result ./options-type-error-typical.nix
+checkConfigError 'Expected an option declaration at option path .result.here. but got an attribute set with type option-type' config.result.here ./options-type-error-typical-nested.nix
+checkConfigError 'Expected an option declaration at option path .result. but got an attribute set with type configuration' config.result ./options-type-error-configuration.nix
+
 # Check that that merging of option collisions doesn't depend on type being set
 checkConfigError 'The option .group..*would be a parent of the following options, but its type .<no description>. does not support nested options.\n\s*- option.s. with prefix .group.enable..*' config.group.enable ./merge-typeless-option.nix
 
diff --git a/lib/tests/modules/options-type-error-configuration.nix b/lib/tests/modules/options-type-error-configuration.nix
new file mode 100644
index 0000000000000..bcd6db89487a3
--- /dev/null
+++ b/lib/tests/modules/options-type-error-configuration.nix
@@ -0,0 +1,6 @@
+{ lib, ... }: {
+  options = {
+    # unlikely mistake, but we can catch any attrset with _type
+    result = lib.evalModules { modules = []; };
+  };
+}
diff --git a/lib/tests/modules/options-type-error-typical-nested.nix b/lib/tests/modules/options-type-error-typical-nested.nix
new file mode 100644
index 0000000000000..2c07e19fb8ae0
--- /dev/null
+++ b/lib/tests/modules/options-type-error-typical-nested.nix
@@ -0,0 +1,5 @@
+{ lib, ... }: {
+  options = {
+    result.here = lib.types.str;
+  };
+}
diff --git a/lib/tests/modules/options-type-error-typical.nix b/lib/tests/modules/options-type-error-typical.nix
new file mode 100644
index 0000000000000..416f436e0ad70
--- /dev/null
+++ b/lib/tests/modules/options-type-error-typical.nix
@@ -0,0 +1,5 @@
+{ lib, ... }: {
+  options = {
+    result = lib.types.str;
+  };
+}