From afad86a9edde5e7d0211721febf5a9493cf1ef58 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Jul 2022 10:48:20 -0400
Subject: [PATCH] fix(types): allow $cond with $in

Fix #12028
---
 test/types/expressions.test.ts | 10 +++++++++-
 types/expressions.d.ts         |  2 +-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/test/types/expressions.test.ts b/test/types/expressions.test.ts
index 433615cc7ff..a078f3a0777 100644
--- a/test/types/expressions.test.ts
+++ b/test/types/expressions.test.ts
@@ -174,7 +174,15 @@ const addWithNull: Expression.Add = {
     '$price',
     { $ifNull: ['$tax', 0] }
   ]
-}
+};
+
+const condWithIn: Expression.Cond = {
+  $cond: {
+    if: { $in: [] },
+    then: '$foo',
+    else: '$bar'
+  }
+};
 
 const toLong: Expression = { $toLong: '$qty' };
 
diff --git a/types/expressions.d.ts b/types/expressions.d.ts
index 221ab22d5a5..10ee0bf1559 100644
--- a/types/expressions.d.ts
+++ b/types/expressions.d.ts
@@ -1043,7 +1043,7 @@ declare module 'mongoose' {
        *
        * @see https://docs.mongodb.com/manual/reference/operator/aggregation/cond/#mongodb-expression-exp.-cond
        */
-      $cond: { if: BooleanExpression | ConditionalExpressionOperator, then: AnyExpression, else: AnyExpression } | [BooleanExpression, AnyExpression, AnyExpression];
+      $cond: { if: Expression, then: AnyExpression, else: AnyExpression } | [BooleanExpression, AnyExpression, AnyExpression];
     }
 
     export interface IfNull {