module tests: add tests for coercedTo

lib/tests/modules.sh

@@ -115,6 +115,11 @@ set -- config.enable ./declare-enable.nix ./define-enable.nix ./define-loaOfSub-
 checkConfigError 'The option .* defined in .* does not exist.' "$@"
 checkConfigOutput "true" "$@" ./define-module-check.nix
 
+# Check coerced value.
+checkConfigOutput "\"42\"" config.value ./declare-coerced-value.nix
+checkConfigOutput "\"24\"" config.value ./declare-coerced-value.nix ./define-value-string.nix
+checkConfigError 'The option value .* in .* is not a coercedTo.' config.value ./declare-coerced-value.nix ./define-value-list.nix
+
 cat <<EOF
 ====== module tests ======
 $pass Pass

lib/tests/modules/declare-coerced-value.nix

@@ -0,0 +1,10 @@
+{ lib, ... }:
+
+{
+  options = {
+    value = lib.mkOption {
+      default = 42;
+      type = lib.types.coercedTo lib.types.int builtins.toString lib.types.str;
+    };
+  };
+}

lib/tests/modules/define-value-list.nix

@@ -0,0 +1,3 @@
+{
+  value = [];
+}

lib/tests/modules/define-value-string.nix

@@ -0,0 +1,3 @@
+{
+  value = "24";
+}