test: Port with-subdir as flake check (#258)

Author: srid

.github/workflows/ci.yaml

@@ -13,10 +13,3 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - run: nixci --build-systems "github:nix-systems/${{ matrix.system }}"
-  # TODO: Remove this job after https://github.com/srid/haskell-flake/issues/241
-  linux-test:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: DeterminateSystems/nix-installer-action@main
-      - run: bash ./runtest.sh

flake.nix

@@ -53,21 +53,20 @@
           };
         };
 
-        test-project-module = {
-          dir = "test/project-module";
+        test-with-subdir = {
+          dir = "test/with-subdir";
           overrideInputs = {
             inherit nixpkgs flake-parts;
             "haskell-flake" = ./.;
           };
         };
 
-        # Legacy shell script test
-        legacy-test = {
-          dir = "test";
-          overrideInputs."haskell-flake" = ./.;
-          # Can't build on Linux until https://github.com/srid/haskell-flake/issues/241
-          # TODO: Do the above, and get rid of this test.
-          systems = [ "aarch64-darwin" "x86_64-darwin" ];
+        test-project-module = {
+          dir = "test/project-module";
+          overrideInputs = {
+            inherit nixpkgs flake-parts;
+            "haskell-flake" = ./.;
+          };
         };
       };
   };

rundoc.sh

@@ -1,11 +1,13 @@
 #!/usr/bin/env sh
 
+# TODO: Move this dev/flake.nix as flake app
+
 if [ -z "$1" ]; then
   nix run github:srid/emanote -- -L ./doc
 else
   # Renders the docs, prints the location of the docs, opens the docs if possible
   #
-  # Does not run the link checker. That's done in runtest.sh.
+  # Does not run the link checker. That's done in nixci checks.
   nix --option sandbox false \
       build ${OVERRIDE_HASKELL_FLAKE} \
       -L --show-trace \

runtest.sh

@@ -12,10 +12,98 @@
       systems = nixpkgs.lib.systems.flakeExposed;
       imports = [
         inputs.haskell-flake.flakeModule
+        ./haskell-flake-patch.nix
       ];
-      perSystem = { self', pkgs, ... }: {
+      debug = true;
+      perSystem = { config, self', pkgs, lib, ... }: {
         haskellProjects.default = { };
-        packages.default = self'.packages.haskell-flake-test;
+
+        # Test the default project by patching and evaluating the result.
+        haskellProjectTests =
+          let
+            pkgOf = projectName: config.haskellProjects.${projectName}.outputs.finalPackages.haskell-flake-test;
+            drvHash = drv: drv.drvPath;
+            deriverHash = drv: drv.cabal2nixDeriver.drvPath;
+          in
+          {
+            # Eval is constant under changes to irrelevant files
+            touch-cabal-project = { name, ... }: {
+              patches = [
+                ''
+                  diff --git a/cabal.project b/cabal.project
+                  index 1a862c3..92dd52b 100644
+                  --- a/cabal.project
+                  +++ b/cabal.project
+                  @@ -1,2 +1,4 @@
+                    packages:
+                  -  ./haskell-flake-test
+                  \ No newline at end of file
+                  +  ./haskell-flake-test
+                  +-- irrelevant comment
+                  +
+                ''
+              ];
+              expect =
+                lib.assertMsg
+                  (lib.all (x: x) [
+                    (drvHash (pkgOf "default") == drvHash (pkgOf name))
+                    (deriverHash (pkgOf "default") == deriverHash (pkgOf name))
+                  ])
+                  "touch-cabal-project failed";
+            };
+
+            # A relevant change to Haskell source causes a .drv change (control check)
+            # But no cabal2nix re-eval
+            touch-src = { name, ... }: {
+              patches = [
+                ''
+                  diff --git a/haskell-flake-test/src/Main.hs b/haskell-flake-test/src/Main.hs
+                  index fa10095..293744c 100644
+                  --- a/haskell-flake-test/src/Main.hs
+                  +++ b/haskell-flake-test/src/Main.hs
+                  @@ -3,3 +3,5 @@ module Main where
+                   main :: IO ()
+                   main = do 
+                     putStrLn "Hello"
+                  +-- irrelevant comment
+                  +
+
+                ''
+              ];
+              expect =
+                lib.assertMsg
+                  (lib.all (x: x) [
+                    (drvHash (pkgOf "default") != drvHash (pkgOf name))
+                    (deriverHash (pkgOf "default") == deriverHash (pkgOf name))
+                  ])
+                  "touch-src failed";
+            };
+
+            # A relevant change to .cabal file causes cabal2nix re-eval
+            touch-cabal = { name, ... }: {
+              patches = [
+                ''
+                  diff --git a/haskell-flake-test/haskell-flake-test.cabal b/haskell-flake-test/haskell-flake-test.cabal
+                  index 950a0ff..ef3131b 100644
+                  --- a/haskell-flake-test/haskell-flake-test.cabal
+                  +++ b/haskell-flake-test/haskell-flake-test.cabal
+                  @@ -16,3 +16,5 @@ executable haskell-flake-test
+                           base
+                       hs-source-dirs:   src
+                       default-language: Haskell2010
+                  +-- irrelevant comment
+                  +
+                ''
+              ];
+              expect =
+                lib.assertMsg
+                  (lib.all (x: x) [
+                    (drvHash (pkgOf "default") != drvHash (pkgOf name))
+                    (deriverHash (pkgOf "default") != deriverHash (pkgOf name))
+                  ])
+                  "touch-src failed";
+            };
+          };
       };
     };
 }

test/common.sh

@@ -0,0 +1,67 @@
+{ self, lib, flake-parts-lib, ... }:
+
+let
+  inherit (flake-parts-lib)
+    mkPerSystemOption;
+  inherit (lib)
+    mkOption
+    types;
+in
+{
+  options.perSystem = mkPerSystemOption ({ config, self', pkgs, ... }: {
+    options = {
+      haskellProjectTests = mkOption {
+        type = types.attrsOf (types.submoduleWith {
+          specialArgs = { inherit pkgs self; };
+          modules = [
+            {
+              options = {
+                from = lib.mkOption {
+                  type = types.str;
+                  default = "default";
+                };
+                patches = lib.mkOption {
+                  type = types.listOf (types.either types.path types.str);
+                  description = ''
+                    List of patches to apply to the project root.
+
+                    Each patch can be a path to the diff file, or inline patch string.
+                  '';
+                };
+                expect = lib.mkOption {
+                  type = types.raw;
+                  description = "Test expectation";
+                };
+              };
+            }
+          ];
+        });
+      };
+    };
+
+    config = {
+      haskellProjects = lib.flip lib.mapAttrs config.haskellProjectTests (name: cfg: {
+        projectRoot = pkgs.applyPatches {
+          name = "haskellProject-patched-${name}";
+          src = config.haskellProjects.${cfg.from}.projectRoot;
+          patches = lib.flip builtins.map cfg.patches (patch:
+            if types.path.check patch then patch else
+            pkgs.writeTextFile {
+              name = "${name}.diff";
+              text = patch;
+            }
+          );
+        };
+      });
+
+      checks = lib.flip lib.mapAttrs config.haskellProjectTests (name: cfg:
+        pkgs.runCommandNoCC "haskell-flake-patch-test-${name}"
+          {
+            EXPECT = builtins.toJSON cfg.expect;
+          }
+          ''touch $out''
+      );
+    };
+  });
+
+}