Refs #373 -- Added additional validations to tuple lookups.

2 files changed, 139 insertions, 7 deletions

diff --git a/django/db/models/fields/tuple_lookups.py b/django/db/models/fields/tuple_lookups.py
index eb2d80b20f..a94582db95 100644
--- a/django/db/models/fields/tuple_lookups.py
+++ b/django/db/models/fields/tuple_lookups.py
@@ -2,7 +2,7 @@ import itertools
 
 from django.core.exceptions import EmptyResultSet
 from django.db.models import Field
-from django.db.models.expressions import Func, Value
+from django.db.models.expressions import ColPairs, Func, Value
 from django.db.models.lookups import (
     Exact,
     GreaterThan,
@@ -28,17 +28,32 @@ class Tuple(Func):
 
 class TupleLookupMixin:
     def get_prep_lookup(self):
+        self.check_rhs_is_tuple_or_list()
         self.check_rhs_length_equals_lhs_length()
         return self.rhs
 
+    def check_rhs_is_tuple_or_list(self):
+        if not isinstance(self.rhs, (tuple, list)):
+            lhs_str = self.get_lhs_str()
+            raise ValueError(
+                f"{self.lookup_name!r} lookup of {lhs_str} must be a tuple or a list"
+            )
+
     def check_rhs_length_equals_lhs_length(self):
         len_lhs = len(self.lhs)
         if len_lhs != len(self.rhs):
+            lhs_str = self.get_lhs_str()
             raise ValueError(
-                f"'{self.lookup_name}' lookup of '{self.lhs.field.name}' field "
-                f"must have {len_lhs} elements"
+                f"{self.lookup_name!r} lookup of {lhs_str} must have {len_lhs} elements"
             )
 
+    def get_lhs_str(self):
+        if isinstance(self.lhs, ColPairs):
+            return repr(self.lhs.field.name)
+        else:
+            names = ", ".join(repr(f.name) for f in self.lhs)
+            return f"({names})"
+
     def get_prep_lhs(self):
         if isinstance(self.lhs, (tuple, list)):
             return Tuple(*self.lhs)
@@ -196,14 +211,25 @@ class TupleLessThanOrEqual(TupleLookupMixin, LessThanOrEqual):
 
 class TupleIn(TupleLookupMixin, In):
     def get_prep_lookup(self):
+        self.check_rhs_is_tuple_or_list()
+        self.check_rhs_is_collection_of_tuples_or_lists()
         self.check_rhs_elements_length_equals_lhs_length()
-        return super(TupleLookupMixin, self).get_prep_lookup()
+        return self.rhs  # skip checks from mixin
+
+    def check_rhs_is_collection_of_tuples_or_lists(self):
+        if not all(isinstance(vals, (tuple, list)) for vals in self.rhs):
+            lhs_str = self.get_lhs_str()
+            raise ValueError(
+                f"{self.lookup_name!r} lookup of {lhs_str} "
+                "must be a collection of tuples or lists"
+            )
 
     def check_rhs_elements_length_equals_lhs_length(self):
         len_lhs = len(self.lhs)
         if not all(len_lhs == len(vals) for vals in self.rhs):
+            lhs_str = self.get_lhs_str()
             raise ValueError(
-                f"'{self.lookup_name}' lookup of '{self.lhs.field.name}' field "
+                f"{self.lookup_name!r} lookup of {lhs_str} "
                 f"must have {len_lhs} elements each"
             )
 
diff --git a/tests/foreign_object/test_tuple_lookups.py b/tests/foreign_object/test_tuple_lookups.py
index e2561676f3..06182d3bb5 100644
--- a/tests/foreign_object/test_tuple_lookups.py
+++ b/tests/foreign_object/test_tuple_lookups.py
@@ -1,3 +1,4 @@
+import itertools
 import unittest
 
 from django.db import NotSupportedError, connection
@@ -129,6 +130,37 @@ class TupleLookupsTests(TestCase):
             (self.contact_1, self.contact_2, self.contact_5),
         )
 
+    def test_tuple_in_rhs_must_be_collection_of_tuples_or_lists(self):
+        test_cases = (
+            (1, 2, 3),
+            ((1, 2), (3, 4), None),
+        )
+
+        for rhs in test_cases:
+            with self.subTest(rhs=rhs):
+                with self.assertRaisesMessage(
+                    ValueError,
+                    "'in' lookup of ('customer_code', 'company_code') "
+                    "must be a collection of tuples or lists",
+                ):
+                    TupleIn((F("customer_code"), F("company_code")), rhs)
+
+    def test_tuple_in_rhs_must_have_2_elements_each(self):
+        test_cases = (
+            ((),),
+            ((1,),),
+            ((1, 2, 3),),
+        )
+
+        for rhs in test_cases:
+            with self.subTest(rhs=rhs):
+                with self.assertRaisesMessage(
+                    ValueError,
+                    "'in' lookup of ('customer_code', 'company_code') "
+                    "must have 2 elements each",
+                ):
+                    TupleIn((F("customer_code"), F("company_code")), rhs)
+
     def test_lt(self):
         c1, c2, c3, c4, c5, c6 = (
             self.contact_1,
@@ -358,8 +390,8 @@ class TupleLookupsTests(TestCase):
             )
 
     def test_lookup_errors(self):
-        m_2_elements = "'%s' lookup of 'customer' field must have 2 elements"
-        m_2_elements_each = "'in' lookup of 'customer' field must have 2 elements each"
+        m_2_elements = "'%s' lookup of 'customer' must have 2 elements"
+        m_2_elements_each = "'in' lookup of 'customer' must have 2 elements each"
         test_cases = (
             ({"customer": 1}, m_2_elements % "exact"),
             ({"customer": (1, 2, 3)}, m_2_elements % "exact"),
@@ -381,3 +413,77 @@ class TupleLookupsTests(TestCase):
                 self.assertRaisesMessage(ValueError, message),
             ):
                 Contact.objects.get(**kwargs)
+
+    def test_tuple_lookup_names(self):
+        test_cases = (
+            (TupleExact, "exact"),
+            (TupleGreaterThan, "gt"),
+            (TupleGreaterThanOrEqual, "gte"),
+            (TupleLessThan, "lt"),
+            (TupleLessThanOrEqual, "lte"),
+            (TupleIn, "in"),
+            (TupleIsNull, "isnull"),
+        )
+
+        for lookup_class, lookup_name in test_cases:
+            with self.subTest(lookup_name):
+                self.assertEqual(lookup_class.lookup_name, lookup_name)
+
+    def test_tuple_lookup_rhs_must_be_tuple_or_list(self):
+        test_cases = itertools.product(
+            (
+                TupleExact,
+                TupleGreaterThan,
+                TupleGreaterThanOrEqual,
+                TupleLessThan,
+                TupleLessThanOrEqual,
+                TupleIn,
+            ),
+            (
+                0,
+                1,
+                None,
+                True,
+                False,
+                {"foo": "bar"},
+            ),
+        )
+
+        for lookup_cls, rhs in test_cases:
+            lookup_name = lookup_cls.lookup_name
+            with self.subTest(lookup_name=lookup_name, rhs=rhs):
+                with self.assertRaisesMessage(
+                    ValueError,
+                    f"'{lookup_name}' lookup of ('customer_code', 'company_code') "
+                    "must be a tuple or a list",
+                ):
+                    lookup_cls((F("customer_code"), F("company_code")), rhs)
+
+    def test_tuple_lookup_rhs_must_have_2_elements(self):
+        test_cases = itertools.product(
+            (
+                TupleExact,
+                TupleGreaterThan,
+                TupleGreaterThanOrEqual,
+                TupleLessThan,
+                TupleLessThanOrEqual,
+            ),
+            (
+                [],
+                [1],
+                [1, 2, 3],
+                (),
+                (1,),
+                (1, 2, 3),
+            ),
+        )
+
+        for lookup_cls, rhs in test_cases:
+            lookup_name = lookup_cls.lookup_name
+            with self.subTest(lookup_name=lookup_name, rhs=rhs):
+                with self.assertRaisesMessage(
+                    ValueError,
+                    f"'{lookup_name}' lookup of ('customer_code', 'company_code') "
+                    "must have 2 elements",
+                ):
+                    lookup_cls((F("customer_code"), F("company_code")), rhs)