ioc/tests/pyepics: init simple test

ioc/tests/default.nix

@@ -4,6 +4,8 @@ with pkgs.lib;
     default-ioc-epics-base-3 = import ./default-ioc "3" args;
     default-ioc-epics-base-7 = import ./default-ioc "7" args;
 
+    pyepics = import ./pyepics args;
+
     support-autosave-simple = import ./support/autosave/simple args;
     support-pvxs-ioc = import ./support/pvxs/ioc args;
     support-pvxs-qsrv2 = import ./support/pvxs/qsrv2 args;

ioc/tests/pyepics/default.nix

@@ -0,0 +1,47 @@
+{pkgs, ...}: let
+  inherit (pkgs) epnixLib lib;
+in
+  pkgs.nixosTest {
+    name = "pytest";
+    meta.maintainers = with epnixLib.maintainers; [minijackson];
+
+    extraPythonPackages = p: [p.pyepics];
+    skipTypeCheck = true;
+
+    nodes.ioc = {
+      imports = [
+        (epnixLib.testing.softIoc ''
+          record(ai, "AI") { }
+          record(stringout, "STRINGOUT") { }
+        '')
+      ];
+    };
+
+    testScript = let
+      python = lib.getExe (pkgs.python3.withPackages (p: [p.pyepics]));
+      iocTestScript = pkgs.writeText "iocTestScript.py" ''
+        import os
+
+        import epics
+
+        os.environ["EPICS_CA_AUTO_ADDR_LIST"] = "NO"
+        os.environ["EPICS_CA_ADDR_LIST"] = "localhost"
+
+        stringout = epics.PV("STRINGOUT")
+
+        assert epics.caget("AI") == 0
+        assert stringout.get() == ""
+
+        assert epics.caput("AI", 42.0, wait=True) == 1
+        assert stringout.put("hello", wait=True) == 1
+
+        assert epics.caget("AI") == 42
+        assert stringout.get() == "hello"
+      '';
+    in ''
+      start_all()
+      ioc.wait_for_unit("ioc.service")
+
+      print(ioc.succeed("${python} ${iocTestScript}"))
+    '';
+  }