From f3e52ede3c110222897c7035fc545fa7c3ccf938 Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Tue, 2 Jun 2020 00:58:36 +0200
Subject: [PATCH 1/3] flake: remove epoch

It was renamed to edition:

https://github.com/NixOS/rfcs/commit/cc5d0a24970a49d7da294544aff2fb3c26139635

leading to the following error:

error: flake 'git+file:///home/jtojnar/Projects/nixflk?ref=template&rev=31c2b767ca7cb901040e388794b34942807719e0' has an unsupported attribute 'epoch', at /nix/store/yndrc91vlh5vm0k4nngx303q1cjm77z9-source/flake.nix:4:3

but that itself has been deprecated:

warning: flake 'git+file:///home/jtojnar/Projects/nixflk' has deprecated attribute 'edition'
---
 flake.nix | 2 --
 1 file changed, 2 deletions(-)

diff --git a/flake.nix b/flake.nix
index 8a50e026..6dbb2572 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,8 +1,6 @@
 {
   description = "A highly structured configuration database.";
 
-  epoch = 201909;
-
   inputs.nixpkgs.url = "nixpkgs/release-20.03";
   inputs.home.url = "github:nrdxp/home-manager/flakes";
 

From 0b14dbbc2df8dc13c4a96dac21092cc6cf8f14a1 Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Tue, 2 Jun 2020 01:14:33 +0200
Subject: [PATCH 2/3] flake: Refactor nixosModules collection

We will want to reuse the prep method for overlays so let's move it higher and simplify it a bit.
---
 flake.nix | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/flake.nix b/flake.nix
index 6dbb2572..ce60012b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -10,6 +10,18 @@
       inherit (nixpkgs.lib) removeSuffix;
       system = "x86_64-linux";
 
+      # Generate an attribute set by mapping a function over a list of values.
+      genAttrs' = values: f: listToAttrs (map f values);
+
+      # Convert a list to file paths to attribute set
+      # that has the filenames stripped of nix extension as keys
+      # and imported content of the file as value.
+      pathsToImportedAttrs = paths:
+        genAttrs' paths (path: {
+          name = removeSuffix ".nix" (baseNameOf path);
+          value = import path;
+        });
+
       pkgs = import nixpkgs {
         inherit system;
         overlays = self.overlays;
@@ -33,18 +45,13 @@
       };
 
       nixosModules = let
-        prep = map (path: {
-          name = removeSuffix ".nix" (baseNameOf path);
-          value = import path;
-        });
-
         # modules
         moduleList = import ./modules/list.nix;
-        modulesAttrs = listToAttrs (prep moduleList);
+        modulesAttrs = pathsToImportedAttrs moduleList;
 
         # profiles
         profilesList = import ./profiles/list.nix;
-        profilesAttrs = { profiles = listToAttrs (prep profilesList); };
+        profilesAttrs = { profiles = pathsToImportedAttrs profilesList; };
 
       in modulesAttrs // profilesAttrs;
     };

From a7749005bc0d6f622cf09aafb936c55c47035e2a Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Tue, 2 Jun 2020 01:17:38 +0200
Subject: [PATCH 3/3] flake: Fix overlays for `nix flake check`

It complains that:

	value is a list while a set was expected, at /nix/store/0qdcc831rj27wz07lrri6bnfmhvm4wrm-source/flake.nix:26:7

But nixpkgs still expects a list, so we need to pass it just the values.
---
 flake.nix | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/flake.nix b/flake.nix
index ce60012b..fe7165d8 100644
--- a/flake.nix
+++ b/flake.nix
@@ -6,7 +6,7 @@
 
   outputs = inputs@{ self, home, nixpkgs }:
     let
-      inherit (builtins) listToAttrs baseNameOf attrNames readDir;
+      inherit (builtins) listToAttrs baseNameOf attrNames attrValues readDir;
       inherit (nixpkgs.lib) removeSuffix;
       system = "x86_64-linux";
 
@@ -24,7 +24,7 @@
 
       pkgs = import nixpkgs {
         inherit system;
-        overlays = self.overlays;
+        overlays = attrValues self.overlays;
         config = { allowUnfree = true; };
       };
 
@@ -35,10 +35,12 @@
 
       overlay = import ./pkgs;
 
-      overlays = let
-        overlays = map (name: import (./overlays + "/${name}"))
-          (attrNames (readDir ./overlays));
-      in overlays;
+      overlays =
+        let
+          overlayDir = ./overlays;
+          fullPath = name: overlayDir + "/${name}";
+          overlayPaths = map fullPath (attrNames (readDir overlayDir));
+        in pathsToImportedAttrs overlayPaths;
 
       packages.x86_64-linux = {
         inherit (pkgs) sddm-chili dejavu_nerdfont purs pure;