5 files changed, 145 insertions, 0 deletions
diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index cde4da6439372..8081b186a2f9f 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -141,6 +141,14 @@ checkConfigError "The option .*enable.* does not exist. Definition values:\n\s*-
 checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-define-enable.nix ./disable-declare-enable.nix
 checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-enable-modules.nix
 
+checkConfigOutput '^true$' 'config.positive.enable' ./disable-module-with-key.nix
+checkConfigOutput '^false$' 'config.negative.enable' ./disable-module-with-key.nix
+checkConfigError 'Module ..*disable-module-bad-key.nix. contains a disabledModules item that is an attribute set, presumably a module, that does not have a .key. attribute. .*' 'config.enable' ./disable-module-bad-key.nix
+
+# Not sure if we want to keep supporting module keys that aren't strings, paths or v?key, but we shouldn't remove support accidentally.
+checkConfigOutput '^true$' 'config.positive.enable' ./disable-module-with-toString-key.nix
+checkConfigOutput '^false$' 'config.negative.enable' ./disable-module-with-toString-key.nix
+
 # Check _module.args.
 set -- config.enable ./declare-enable.nix ./define-enable-with-custom-arg.nix
 checkConfigError 'while evaluating the module argument .*custom.* in .*define-enable-with-custom-arg.nix.*:' "$@"
@@ -358,6 +366,10 @@ checkConfigOutput '^"The option `a\.b. defined in `.*/doRename-warnings\.nix. ha
   config.result \
   ./doRename-warnings.nix
 
+# Anonymous modules get deduplicated by key
+checkConfigOutput '^"pear"$' config.once.raw ./merge-module-with-key.nix
+checkConfigOutput '^"pear\\npear"$' config.twice.raw ./merge-module-with-key.nix
+
 cat <<EOF
 ====== module tests ======
 $pass Pass
diff --git a/lib/tests/modules/disable-module-bad-key.nix b/lib/tests/modules/disable-module-bad-key.nix
new file mode 100644
index 0000000000000..f50d06f2f03cd
--- /dev/null
+++ b/lib/tests/modules/disable-module-bad-key.nix
@@ -0,0 +1,16 @@
+{ lib, ... }:
+let
+  inherit (lib) mkOption types;
+
+  moduleWithKey = { config, ... }: {
+    config = {
+      enable = true;
+    };
+  };
+in
+{
+  imports = [
+    ./declare-enable.nix
+  ];
+  disabledModules = [ { } ];
+}
diff --git a/lib/tests/modules/disable-module-with-key.nix b/lib/tests/modules/disable-module-with-key.nix
new file mode 100644
index 0000000000000..ea2a60aa832d0
--- /dev/null
+++ b/lib/tests/modules/disable-module-with-key.nix
@@ -0,0 +1,34 @@
+{ lib, ... }:
+let
+  inherit (lib) mkOption types;
+
+  moduleWithKey = {
+    key = "disable-module-with-key.nix#moduleWithKey";
+    config = {
+      enable = true;
+    };
+  };
+in
+{
+  options = {
+    positive = mkOption {
+      type = types.submodule {
+        imports = [
+          ./declare-enable.nix
+          moduleWithKey
+        ];
+      };
+      default = {};
+    };
+    negative = mkOption {
+      type = types.submodule {
+        imports = [
+          ./declare-enable.nix
+          moduleWithKey
+        ];
+        disabledModules = [ moduleWithKey ];
+      };
+      default = {};
+    };
+  };
+}
diff --git a/lib/tests/modules/disable-module-with-toString-key.nix b/lib/tests/modules/disable-module-with-toString-key.nix
new file mode 100644
index 0000000000000..3f8c81904ce67
--- /dev/null
+++ b/lib/tests/modules/disable-module-with-toString-key.nix
@@ -0,0 +1,34 @@
+{ lib, ... }:
+let
+  inherit (lib) mkOption types;
+
+  moduleWithKey = {
+    key = 123;
+    config = {
+      enable = true;
+    };
+  };
+in
+{
+  options = {
+    positive = mkOption {
+      type = types.submodule {
+        imports = [
+          ./declare-enable.nix
+          moduleWithKey
+        ];
+      };
+      default = {};
+    };
+    negative = mkOption {
+      type = types.submodule {
+        imports = [
+          ./declare-enable.nix
+          moduleWithKey
+        ];
+        disabledModules = [ 123 ];
+      };
+      default = {};
+    };
+  };
+}
diff --git a/lib/tests/modules/merge-module-with-key.nix b/lib/tests/modules/merge-module-with-key.nix
new file mode 100644
index 0000000000000..21f00e6ef9766
--- /dev/null
+++ b/lib/tests/modules/merge-module-with-key.nix
@@ -0,0 +1,49 @@
+{ lib, ... }:
+let
+  inherit (lib) mkOption types;
+
+  moduleWithoutKey = {
+    config = {
+      raw = "pear";
+    };
+  };
+
+  moduleWithKey = {
+    key = __curPos.file + "#moduleWithKey";
+    config = {
+      raw = "pear";
+    };
+  };
+
+  decl = {
+    options = {
+      raw = mkOption {
+        type = types.lines;
+      };
+    };
+  };
+in
+{
+  options = {
+    once = mkOption {
+      type = types.submodule {
+        imports = [
+          decl
+          moduleWithKey
+          moduleWithKey
+        ];
+      };
+      default = {};
+    };
+    twice = mkOption {
+      type = types.submodule {
+        imports = [
+          decl
+          moduleWithoutKey
+          moduleWithoutKey
+        ];
+      };
+      default = {};
+    };
+  };
+}