From 512c62248769ce3a92cf433ded2bb53db58f281c Mon Sep 17 00:00:00 2001
From: barredterra <14891507+barredterra@users.noreply.github.com>
Date: Mon, 21 Mar 2022 20:51:35 +0100
Subject: [PATCH 1/2] test: make sure `exists` doesn't eat the doctype key

---
 frappe/tests/test_db.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/frappe/tests/test_db.py b/frappe/tests/test_db.py
index 19b683aa75..10c601db00 100644
--- a/frappe/tests/test_db.py
+++ b/frappe/tests/test_db.py
@@ -327,7 +327,13 @@ class TestDB(unittest.TestCase):
 		self.assertEqual(frappe.db.exists(dt, dn, cache=True), dn)
 		self.assertEqual(frappe.db.exists(dt, dn), dn)
 		self.assertEqual(frappe.db.exists(dt, {"name": ("=", dn)}), dn)
-		self.assertEqual(frappe.db.exists({"doctype": dt, "name": ("like", "Admin%")}), dn)
+
+		filters = {"doctype": dt, "name": ("like", "Admin%")}
+		self.assertEqual(frappe.db.exists(filters), dn)
+		self.assertEqual(
+			filters["doctype"], dt
+		)  # make sure that doctype was not removed from filters
+
 		self.assertEqual(frappe.db.exists(dt, [["name", "=", dn]]), dn)
 
 

From 44a7c0dd9318d984b20ae95180f5cf35eb146c28 Mon Sep 17 00:00:00 2001
From: barredterra <14891507+barredterra@users.noreply.github.com>
Date: Mon, 21 Mar 2022 20:51:59 +0100
Subject: [PATCH 2/2] fix: copy dict before popping keys

---
 frappe/database/database.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/frappe/database/database.py b/frappe/database/database.py
index b1b5abffca..82a7e6f919 100644
--- a/frappe/database/database.py
+++ b/frappe/database/database.py
@@ -919,8 +919,8 @@ class Database(object):
 			return dn
 
 		if isinstance(dt, dict):
-			_dt = dt.pop("doctype")
-			dt, dn = _dt, dt
+			dt = dt.copy() # don't modify the original dict
+			dt, dn = dt.pop("doctype"), dt
 
 		return self.get_value(dt, dn, ignore=True, cache=cache)