Setup Regal to lint policies and clean them up

policies/register/register_test.rego

@@ -0,0 +1,58 @@
+package register_test
+
+import data.register
+import rego.v1
+
+mock_registration := {
+	"registration_method": "password",
+	"username": "hello",
+	"email": "hello@staging.element.io",
+}
+
+test_allow_all_domains if {
+	register.allow with input as mock_registration
+}
+
+test_allowed_domain if {
+	register.allow with input as mock_registration
+		with data.allowed_domains as ["*.element.io"]
+}
+
+test_not_allowed_domain if {
+	not register.allow with input as mock_registration
+		with data.allowed_domains as ["example.com"]
+}
+
+test_banned_domain if {
+	not register.allow with input as mock_registration
+		with data.banned_domains as ["*.element.io"]
+}
+
+test_banned_subdomain if {
+	not register.allow with input as mock_registration
+		with data.allowed_domains as ["*.element.io"]
+		with data.banned_domains as ["staging.element.io"]
+}
+
+test_email_required if {
+	not register.allow with input as {"username": "hello", "registration_method": "password"}
+}
+
+test_no_email if {
+	register.allow with input as {"username": "hello", "registration_method": "upstream-oauth2"}
+}
+
+test_short_username if {
+	not register.allow with input as {"username": "a", "registration_method": "upstream-oauth2"}
+}
+
+test_long_username if {
+	not register.allow with input as {
+		"username": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+		"registration_method": "upstream-oauth2",
+	}
+}
+
+test_invalid_username if {
+	not register.allow with input as {"username": "hello world", "registration_method": "upstream-oauth2"}
+}