Add the tool "nixos-typecheck" that can check an option declaration to:

 - Enforce that an option declaration has a "defaultText" if and only if the
   type of the option derives from "package", "packageSet" or "nixpkgsConfig"
   and if a "default" attribute is defined.

 - Enforce that the value of the "example" attribute is wrapped with "literalExample"
   if the type of the option derives from "package", "packageSet" or "nixpkgsConfig".

 - Warn if a "defaultText" is defined in an option declaration if the type of
   the option does not derive from "package", "packageSet" or "nixpkgsConfig".

 - Warn if no "type" is defined in an option declaration.

1 files changed, 1 insertions, 0 deletions

diff --git a/nixos/modules/config/sysctl.nix b/nixos/modules/config/sysctl.nix
index 61b02c5ffa6..174d7014ca8 100644
--- a/nixos/modules/config/sysctl.nix
+++ b/nixos/modules/config/sysctl.nix
@@ -6,6 +6,7 @@ let
 
   sysctlOption = mkOptionType {
     name = "sysctl option value";
+    typerep = "(sysctl)";
     check = val:
       let
         checkType = x: isBool x || isString x || isInt x || isNull x;