Revert auto-channel detection that produced irrecoverable edge-cases

.github/workflows/ci.yaml

@@ -20,7 +20,6 @@ jobs:
 
       # Execute /tests/*
       - run: nix develop --command check-derivation-outputs
-      - run: nix develop --command check-derivation-outputs-old
       - run: nix develop --command check-channel-patching
       - run: nix develop --command check-overlays-flow
       - run: nix develop --command check-hosts-config

devShell.nix

@@ -70,10 +70,9 @@ devshell.mkShell {
 
     (test "channel-patching")
     (test "derivation-outputs")
-    (test "derivation-outputs-old")
     (test "hosts-config")
     (test "overlays-flow")
-    (test "all" // { command = "check-channel-patching && check-derivation-outputs && check-derivation-outputs-old && check-hosts-config && check-overlays-flow"; })
+    (test "all" // { command = "check-channel-patching && check-derivation-outputs && check-hosts-config && check-overlays-flow"; })
 
     (dry-nixos-build "minimal-multichannel" "Hostname1")
     (dry-nixos-build "minimal-multichannel" "Hostname2")

examples/exporters/flake.nix

@@ -16,6 +16,7 @@
       inherit self inputs;
 
       # Channel specific overlays. Overlays `coreutils` from `unstable` channel.
+      channels.unstable = { };
       channels.nixpkgs.overlaysBuilder = channels: [
         (final: prev: { inherit (channels.unstable) ranger; })
       ];

examples/home-manager+nur+neovim/flake.nix

@@ -26,6 +26,7 @@
 
 
       channelsConfig.allowUnfree = true;
+      channels.nixpkgs = { };
 
       sharedOverlays = [
         nur.overlay

examples/minimal-multichannel/flake.nix

@@ -16,6 +16,8 @@
       # Channels are automatically generated from nixpkgs inputs
       # e.g the inputs which contain `legacyPackages` attribute are used.
       channelsConfig.allowUnfree = true;
+      channels.nixpkgs = { };
+      channels.unstable = { };
 
 
       # Modules shared between all hosts

flake.nix

@@ -24,26 +24,16 @@
     rec {
       inherit overlay;
 
-      # Deprecated in favor of 'nix.generateRegistryFromInputs = true;'
-      nixosModules.saneFlakeDefaults = { nix.generateRegistryFromInputs = true; };
       nixosModules.autoGenFromInputs = import ./lib/options.nix;
 
       devShell.x86_64-linux = import ./devShell.nix { system = "x86_64-linux"; };
 
       lib = flake-utils.lib // {
-        inherit mkFlake exportModules exportOverlays exportPackages;
-
-        # Deprecated - should use top-level functions instead
-        exporters = {
-          inherit modulesFromList fromOverlays internalOverlays;
-        };
-        inherit systemFlake modulesFromList;
+        inherit mkFlake exportModules exportOverlays exportPackages systemFlake modulesFromList;
 
         # DO NOT USE - subject to change without notice
         internal = internal-functions;
 
-        repl = ./lib/repl.nix;
-
         # merge nested attribute sets and lists
         mergeAny = lhs: rhs:
           lhs // mapAttrs

lib/mkFlake.nix

@@ -1,32 +1,18 @@
 { flake-utils-plus }:
 
 { self
-, defaultSystem ? "x86_64-linux" # will be deprecated soon use hostDefaults.system instead
 , supportedSystems ? flake-utils-plus.lib.defaultSystems
 , inputs
-
 , channels ? { }
 , channelsConfig ? { }
 , sharedOverlays ? [ ]
-
-, nixosProfiles ? { } # will be deprecated soon, use hosts, instead.
-, hosts ? nixosProfiles
-, sharedExtraArgs ? { } # deprecate soon, prefer hostDefaults
-, sharedModules ? [ ] # deprecate soon, prefer hostDefaults
+, hosts ? { }
 , hostDefaults ? {
-    system = defaultSystem;
-    modules = sharedModules;
-    extraArgs = sharedExtraArgs;
+    system = "x86_64-linux";
+    modules = [ ];
+    extraArgs = { };
   }
-
-, outputsBuilder ? null
-
-, packagesBuilder ? null
-, defaultPackageBuilder ? null
-, appsBuilder ? null
-, defaultAppBuilder ? null
-, devShellBuilder ? null
-, checksBuilder ? null
+, outputsBuilder ? _: { }
 , ...
 }@args:
 
@@ -82,29 +68,30 @@ let
   optionalAttrs = check: value: if check then value else { };
 
   otherArguments = removeAttrs args [
-    "defaultSystem" # TODO: deprecated, remove
-    "sharedExtraArgs" # deprecated
     "inputs"
     "hosts"
     "hostDefaults"
     "nixosProfiles"
     "channels"
     "channelsConfig"
     "self"
-    "sharedModules" # deprecated
     "sharedOverlays"
     "supportedSystems"
-
-    "outputsBuilder"
-    "packagesBuilder"
-    "defaultPackageBuilder"
-    "appsBuilder"
-    "defaultAppBuilder"
-    "devShellBuilder"
-    "checksBuilder"
   ];
 
   getChannels = system: self.pkgs.${system};
+  ensureChannelsWitsInputs = mapAttrs
+    (n: v:
+      if (!v ? input) then
+        v // {
+          input = inputs.${n} or (
+            throw ''
+              No input is inferable by name from flake inputs for channel "${n}"
+            '');
+        }
+      else v
+    )
+    channels;
   getNixpkgs = host: (getChannels host.system).${host.channelName};
 
   configurationBuilder = reverseDomainName: host': (
@@ -121,7 +108,7 @@ let
       selectedNixpkgs = getNixpkgs host;
       host = evalHostArgs (mergeAny hostDefaults host');
       patchedChannel = selectedNixpkgs.path;
-      channels = getChannels host.system;
+      channels' = getChannels host.system;
 
       specialArgs = host.specialArgs // { channel = selectedNixpkgs; };
 
@@ -133,10 +120,10 @@ let
       nixosSpecialArgs =
         let
           f = channelName:
-            { "${channelName}ModulesPath" = toString (channels.${channelName}.input + "/nixos/modules"); };
+            { "${channelName}ModulesPath" = toString (channels'.${channelName}.input + "/nixos/modules"); };
         in
         # Add `<channelName>ModulesPath`s
-        (foldl' (lhs: rhs: lhs // rhs) { } (map f (attrNames channels)))
+        (foldl' (lhs: rhs: lhs // rhs) { } (map f (attrNames channels')))
         # Override `modulesPath` because otherwise imports from there will not use patched nixpkgs
         // { modulesPath = toString (patchedChannel + "/nixos/modules"); };
 
@@ -220,14 +207,6 @@ mergeAny otherArguments (
   eachSystem supportedSystems
     (system:
       let
-        filterAttrs = pred: set:
-          listToAttrs (concatMap (name: let value = set.${name}; in if pred name value then [ ({ inherit name value; }) ] else [ ]) (attrNames set));
-
-        # Little hack, we make sure that `legacyPackages` contains `nix` to make sure that we are dealing with nixpkgs.
-        # For some odd reason `devshell` contains `legacyPackages` out put as well
-        channelFlakes = filterAttrs (_: value: value ? legacyPackages && value.legacyPackages.x86_64-linux ? nix) inputs;
-        channelsFromFlakes = mapAttrs (name: input: { inherit input; }) channelFlakes;
-
         importChannel = name: value: (import (patchChannel system value.input (value.patches or [ ])) {
           inherit system;
           overlays = [
@@ -239,18 +218,9 @@ mergeAny otherArguments (
           config = channelsConfig // (value.config or { });
         }) // { inherit name; inherit (value) input; };
 
-        pkgs = mapAttrs importChannel (mergeAny channelsFromFlakes channels);
-
-
-        deprecatedBuilders = channels: { }
-        // optionalAttrs (packagesBuilder != null) { packages = packagesBuilder channels; }
-        // optionalAttrs (defaultPackageBuilder != null) { defaultPackage = defaultPackageBuilder channels; }
-        // optionalAttrs (appsBuilder != null) { apps = appsBuilder channels; }
-        // optionalAttrs (defaultAppBuilder != null) { defaultApp = defaultAppBuilder channels; }
-        // optionalAttrs (devShellBuilder != null) { devShell = devShellBuilder channels; }
-        // optionalAttrs (checksBuilder != null) { checks = checksBuilder channels; };
+        pkgs = mapAttrs importChannel ensureChannelsWitsInputs;
 
-        systemOutputs = (if outputsBuilder == null then deprecatedBuilders else outputsBuilder) pkgs;
+        systemOutputs = outputsBuilder pkgs;
 
         mkOutputs = attrs: output:
           attrs //