chore: add semgrep test correctness rules and fix teardown

Author: ravibharathi656

payments/payment_gateways/doctype/mpesa_settings/test_mpesa_settings.py

@@ -45,7 +45,7 @@ def setUp(self):
 		)
 
 	def tearDown(self):
-		frappe.db.rollback()
+		super().tearDown()
 		for x in frappe.db.get_all("POS Opening Entry"):
 			frappe.get_doc("POS Opening Entry", x.name).cancel().delete()
 		frappe.db.sql("delete from `tabMpesa Settings`")

semgrep/test-correctness.yml

@@ -0,0 +1,24 @@
+rules:
+- id: Dont-commit
+  pattern: frappe.db.commit()
+  message: Commiting inside test breaks idempotency.
+  languages: [python]
+  severity: ERROR
+- id: Implicit-commit
+  pattern: frappe.db.truncate()
+  message: DB truncation does implict commit which breaks test idempotency.
+  languages: [python]
+  severity: ERROR
+- id: Dont-override-teardown
+  patterns:
+  - pattern: |
+      def tearDown(...):
+        ...
+  - pattern-not: |
+      def tearDown(...):
+        ...
+        super().tearDown()
+        ...
+  message: PaymentsTestSuite forces rollback on each tearDown, which ensures idempotency. Don't override tearDown.
+  languages: [python]
+  severity: ERROR