From d3dcb10e3ddab3174c4c1d1ad8ffbd2dd5b783da Mon Sep 17 00:00:00 2001
From: Greg Manning <greg@gregmanning.uk>
Date: Tue, 13 Aug 2024 00:57:28 +0100
Subject: [PATCH] trying to do github actions

---
 .github/workflows/nix-github-actions.yml | 33 ++++++++++++++++++++++++
 flake.lock                               | 21 +++++++++++++++
 flake.nix                                | 12 +++++++--
 3 files changed, 64 insertions(+), 2 deletions(-)
 create mode 100644 .github/workflows/nix-github-actions.yml

diff --git a/.github/workflows/nix-github-actions.yml b/.github/workflows/nix-github-actions.yml
new file mode 100644
index 0000000..4b90626
--- /dev/null
+++ b/.github/workflows/nix-github-actions.yml
@@ -0,0 +1,33 @@
+name: Nix Flake actions
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+      - main
+
+jobs:
+  nix-matrix:
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.set-matrix.outputs.matrix }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v27
+      - id: set-matrix
+        name: Generate Nix Matrix
+        run: |
+          set -Eeu
+          matrix="$(nix eval --json '.#githubActions.matrix')"
+          echo "matrix=$matrix" >> "$GITHUB_OUTPUT"
+
+  nix-build:
+    needs: nix-matrix
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix: ${{fromJSON(needs.nix-matrix.outputs.matrix)}}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v27
+      - run: nix build -L '.#${{ matrix.attr }}'
diff --git a/flake.lock b/flake.lock
index 685c82c..707234d 100644
--- a/flake.lock
+++ b/flake.lock
@@ -50,6 +50,26 @@
         "type": "github"
       }
     },
+    "nix-github-actions": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1720066371,
+        "narHash": "sha256-uPlLYH2S0ACj0IcgaK9Lsf4spmJoGejR9DotXiXSBZQ=",
+        "owner": "nix-community",
+        "repo": "nix-github-actions",
+        "rev": "622f829f5fe69310a866c8a6cd07e747c44ef820",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "repo": "nix-github-actions",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1723175592,
@@ -71,6 +91,7 @@
         "flake-utils": "flake-utils",
         "javelin": "javelin",
         "javelin-rp2040": "javelin-rp2040",
+        "nix-github-actions": "nix-github-actions",
         "nixpkgs": "nixpkgs"
       }
     },
diff --git a/flake.nix b/flake.nix
index 603a3e9..54a1bf1 100644
--- a/flake.nix
+++ b/flake.nix
@@ -11,10 +11,17 @@
       url = "github:jthlim/javelin-steno-rp2040";
       flake = false;
     };
-    flake-utils.url = "github:numtide/flake-utils";
+    flake-utils = {
+      url = "github:numtide/flake-utils";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    nix-github-actions = {
+      url = "github:nix-community/nix-github-actions";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
-  outputs = { self, nixpkgs, flake-utils, javelin, javelin-rp2040 }: 
+  outputs = { self, nixpkgs, flake-utils, javelin, javelin-rp2040, nix-github-actions }: 
     flake-utils.lib.eachDefaultSystem (system: 
     let 
       pkgs = import nixpkgs {
@@ -32,6 +39,7 @@
       deps = with pkgs; [ cmake gcc-arm-embedded local-pico-sdk python3];
       my_yask_file = ./yask.h;
     in rec { 
+      githubActions = nix-github-actions.lib.mkGithubMatrix { checks = self.packages; };
       packages.default = pkgs.stdenv.mkDerivation {
         name = "javelin-rp2040";
         src = javelin-rp2040;