1 files changed, 70 insertions, 0 deletions
diff --git a/lib/ci.nix b/lib/ci.nix
new file mode 100644
index 0000000..1911a11
--- /dev/null
+++ b/lib/ci.nix
@@ -0,0 +1,70 @@
+lib: supportedSystems: let
+  inherit (builtins) attrNames baseNameOf elem getContext head mapAttrs seq stringLength substring;
+  inherit (lib) filterAttrs;
+  check = string: elem string supportedSystems;
+in rec {
+  # filters systems in basic flake output
+  # ex:
+  #
+  #	packages = {
+  #	  x86_64-linux = {};
+  #	  aarch64-linux = {};
+  #	  x86_64-darwin = {};
+  #	  aarch64-darwin = {};
+  #	};
+  # mkCompatible packages -> { x86_64-linux = {}; aarch64-linux = {}; }
+  mkCompatible = filterAttrs (system: _: check system);
+
+  # mkCompatible but for apps, since their attribute
+  # also needs to be editied in order to be picked up
+  # by some ci systems
+  mkCompatibleApps = apps:
+    mkCompatible (mapAttrs (
+        _:
+          mapAttrs (_: v: {
+            program = let
+              ctx = getContext v.program;
+              drvPath = head (attrNames ctx);
+              basename = baseNameOf drvPath;
+              hashLength = 33;
+              l = stringLength basename;
+            in {
+              name = substring hashLength (l - hashLength - 4) basename;
+              type = "derivation";
+              inherit drvPath;
+            };
+          })
+      )
+      apps);
+
+  # mkCompatible but for formatters
+  mkCompatibleFormatters = filterAttrs (system: fmt: check system && elem system (fmt.meta.platforms or []));
+
+  # mkComaptible, but maps nixosConfigurations
+  # to their toplevel build attribute so they can
+  # be picked up by hydra
+  mkCompatibleCfg = configs:
+    filterAttrs (_: config: check config.system)
+    (mapAttrs (_: v: v.config.system.build.toplevel) configs);
+
+  # mkCompatibleCfg, but the toplevel build attribute
+  # is only evaluated
+  mkCompatibleCfg' = configs:
+    filterAttrs (_: config: check config.system)
+    (mapAttrs (_: v:
+      seq
+      v.config.system.build.toplevel
+      v._module.args.pkgs.emptyFile)
+    configs);
+
+  # mkCompatible, but maps homeConfigurations
+  # to their activationPackage so they can be
+  # picked up by hydra
+  mkCompatibleHM = configs:
+    filterAttrs (system: _: check system)
+    (mapAttrs (_: mapAttrs (_: deriv: deriv.activationPackage or {})) configs);
+
+  # mkCompatible, but for packages
+  # meta.platforms is also checked to ensure compatibility
+  mkCompatiblePkgs = mapAttrs (system: filterAttrs (_: deriv: elem system (deriv.meta.platforms or [])));
+}