From 63908e733fcf3f20ce961f868d58b06b35bc1a93 Mon Sep 17 00:00:00 2001
From: Silvan Mosberger <contact@infinisil.com>
Date: Sun, 27 Sep 2020 17:15:57 +0200
Subject: [PATCH 1/2] lib/tests: Add submodule file propagation test

---
 lib/tests/modules.sh                 |  4 ++++
 lib/tests/modules/submoduleFiles.nix | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 lib/tests/modules/submoduleFiles.nix

diff --git a/lib/tests/modules.sh b/lib/tests/modules.sh
index 309c5311361c1..176c20a28419c 100755
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -179,6 +179,10 @@ checkConfigOutput "true" config.submodule.outer ./declare-submoduleWith-modules.
 ## Paths should be allowed as values and work as expected
 checkConfigOutput "true" config.submodule.enable ./declare-submoduleWith-path.nix
 
+# Check the file location information is propagated into submodules
+checkConfigOutput the-file.nix config.submodule.internalFiles.0 ./submoduleFiles.nix
+
+
 # Check that disabledModules works recursively and correctly
 checkConfigOutput "true" config.enable ./disable-recursive/main.nix
 checkConfigOutput "true" config.enable ./disable-recursive/{main.nix,disable-foo.nix}
diff --git a/lib/tests/modules/submoduleFiles.nix b/lib/tests/modules/submoduleFiles.nix
new file mode 100644
index 0000000000000..c0d9b2cef3e8d
--- /dev/null
+++ b/lib/tests/modules/submoduleFiles.nix
@@ -0,0 +1,21 @@
+{ lib, ... }: {
+  options.submodule = lib.mkOption {
+    default = {};
+    type = lib.types.submoduleWith {
+      modules = [ ({ options, ... }: {
+        options.value = lib.mkOption {};
+
+        options.internalFiles = lib.mkOption {
+          default = options.value.files;
+        };
+      })];
+    };
+  };
+
+  imports = [
+    {
+      _file = "the-file.nix";
+      submodule.value = 10;
+    }
+  ];
+}

From e1aa9a8ab5e39838dc110b663e89658ca1e83c37 Mon Sep 17 00:00:00 2001
From: Silvan Mosberger <contact@infinisil.com>
Date: Sun, 27 Sep 2020 16:39:57 +0200
Subject: [PATCH 2/2] lib/types: Simplify submoduleWith
 shorthandOnlyDefinesConfig handling

The module system already uses the parent modules _type as a fallback,
so we don't need to inject the file in a weird way
---
 lib/types.nix | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/lib/types.nix b/lib/types.nix
index ee891f8231b60..cbf82a3760ed2 100644
--- a/lib/types.nix
+++ b/lib/types.nix
@@ -467,15 +467,10 @@ rec {
       let
         inherit (lib.modules) evalModules;
 
-        coerce = unify: value: if isFunction value
-          then setFunctionArgs (args: unify (value args)) (functionArgs value)
-          else unify (if shorthandOnlyDefinesConfig then { config = value; } else value);
-
         allModules = defs: modules ++ imap1 (n: { value, file }:
-          if isAttrs value || isFunction value then
-            # Annotate the value with the location of its definition for better error messages
-            coerce (lib.modules.unifyModuleSyntax file "${toString file}-${toString n}") value
-          else value
+          if isAttrs value && shorthandOnlyDefinesConfig
+          then { _file = file; config = value; }
+          else { _file = file; imports = [ value ]; }
         ) defs;
 
         freeformType = (evalModules {