From c3f9d584a4e59eac7a8267336f7a774a570a21d4 Mon Sep 17 00:00:00 2001
From: Mathias Vorreiter Pedersen <mathiasvp@github.com>
Date: Wed, 13 Oct 2021 09:48:57 +0000
Subject: [PATCH] QL: Add query that finds 'if p() then q() else none()'.

---
 ql/src/queries/style/IfWithElseNone.ql | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 ql/src/queries/style/IfWithElseNone.ql

diff --git a/ql/src/queries/style/IfWithElseNone.ql b/ql/src/queries/style/IfWithElseNone.ql
new file mode 100644
index 00000000000..c563c28e9f8
--- /dev/null
+++ b/ql/src/queries/style/IfWithElseNone.ql
@@ -0,0 +1,15 @@
+/**
+ * @name Use of 'if' with a 'none()' branch.
+ * @description Using 'if p() then q() else none()' is bad style. It should be rewritten as 'p() and q()'.
+ * @kind problem
+ * @problem.severity warning
+ * @id ql/if-with-none
+ * @precision very-high
+ * @tags maintainability
+ */
+
+import ql
+
+from IfFormula ifFormula
+where ifFormula.getElsePart() instanceof NoneCall or ifFormula.getThenPart() instanceof NoneCall
+select ifFormula, "Use a conjunction instead."