add test case for error inside variables.

staging/src/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/typechecking_test.go

@@ -502,6 +502,35 @@ func TestTypeCheck(t *testing.T) {
 				toContain("found no matching overload for '_==_' applied to '(string, int)"),
 			},
 		},
+		{
+			name: "error in variables, not reported during type checking.",
+			policy: &v1beta1.ValidatingAdmissionPolicy{Spec: v1beta1.ValidatingAdmissionPolicySpec{
+				Variables: []v1beta1.Variable{
+					{
+						Name:       "name",
+						Expression: "object.foo == 'str'",
+					},
+				},
+				Validations: []v1beta1.Validation{
+					{
+						Expression: "variables.name == object.foo", // foo is int64
+					},
+				},
+				MatchConstraints: deploymentPolicy.Spec.MatchConstraints,
+			},
+			},
+			schemaToReturn: &spec.Schema{
+				SchemaProps: spec.SchemaProps{
+					Type: []string{"object"},
+					Properties: map[string]spec.Schema{
+						"foo": *spec.Int64Property(),
+					},
+				},
+			},
+			assertions: []assertionFunc{
+				toHaveLengthOf(0),
+			},
+		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			typeChecker := buildTypeChecker(tc.schemaToReturn)