substituteAll: validate arguments

So no one can repeat my mistakes.

pkgs/build-support/substitute/substitute-all.nix

@@ -1,12 +1,22 @@
-{ stdenvNoCC }:
-
-args:
-
+{ lib, stdenvNoCC }:
 # see the substituteAll in the nixpkgs documentation for usage and constraints
-stdenvNoCC.mkDerivation ({
+args:
+let
+  # keep this in sync with substituteAll
+  isInvalidArgName = x: builtins.match "^[a-z][a-zA-Z0-9_]*$" x == null;
+  invalidArgs = builtins.filter isInvalidArgName (builtins.attrNames args);
+in
+  if invalidArgs == [] then
+    stdenvNoCC.mkDerivation ({
       name = if args ? name then args.name else baseNameOf (toString args.src);
       builder = ./substitute-all.sh;
       inherit (args) src;
       preferLocalBuild = true;
       allowSubstitutes = false;
-} // args)
+    } // args)
+  else throw ''
+    Argument names for `pkgs.substituteAll` must:
+      - start with a lower case ASCII letter
+      - only contain ASCII letters, digits and underscores
+    Found invalid argument names: ${lib.concatStringsSep ", " invalidArgs}.
+  ''