Add build action on nixostests blocktype

src/std/fwlib/blockTypes/nixostests.nix

@@ -7,6 +7,7 @@ Use the NixosTests Blocktype in order to instrucement nixos
 vm-based test inside your reporisory.
 
 Available actions:
+  - build
   - run
   - run-vm
   - audit-script
@@ -32,6 +33,7 @@ in
       inherit (pkgs.stdenv) isLinux;
     in
       [
+        (actions.build currentSystem target)
         (mkCommand currentSystem "run" "run tests in headless vm" [] ''
           # ${target.driver}
           ${target.driver}/bin/nixos-test-driver

tests/_snapshots/bt-blocktypes

@@ -255,6 +255,13 @@
   };
   nixostests = {
     actions = [
+      {
+        command = <derivation build>;
+        description = "build it";
+        name = "build";
+        proviso = "std/fwlib/actions/build-proviso.sh";
+        targetDrv = "drvPath";
+      }
       {
         command = <derivation run>;
         description = "run tests in headless vm";

tests/bt-blocktypes/expr.nix

@@ -33,6 +33,8 @@
       configFile = "path/to/configFile";
     };
     nixostests = {
+      drvPath = "drvPath";
+      outPath = "outPath";
       driver = "driver";
       driverInteractive = "driverInteractive";
     };