Fixed #31902 -- Fixed crash of ExclusionConstraint on expressions with params.

2 files changed, 17 insertions, 4 deletions

diff --git a/django/contrib/postgres/constraints.py b/django/contrib/postgres/constraints.py
index 2ae72c402e..12c185a777 100644
--- a/django/contrib/postgres/constraints.py
+++ b/django/contrib/postgres/constraints.py
@@ -66,20 +66,21 @@ class ExclusionConstraint(BaseConstraint):
         self.opclasses = opclasses
         super().__init__(name=name)
 
-    def _get_expression_sql(self, compiler, connection, query):
+    def _get_expression_sql(self, compiler, schema_editor, query):
         expressions = []
         for idx, (expression, operator) in enumerate(self.expressions):
             if isinstance(expression, str):
                 expression = F(expression)
             expression = expression.resolve_expression(query=query)
-            sql, params = expression.as_sql(compiler, connection)
+            sql, params = expression.as_sql(compiler, schema_editor.connection)
             try:
                 opclass = self.opclasses[idx]
                 if opclass:
                     sql = '%s %s' % (sql, opclass)
             except IndexError:
                 pass
-            expressions.append('%s WITH %s' % (sql % params, operator))
+            sql = sql % tuple(schema_editor.quote_value(p) for p in params)
+            expressions.append('%s WITH %s' % (sql, operator))
         return expressions
 
     def _get_condition_sql(self, compiler, schema_editor, query):
@@ -92,7 +93,7 @@ class ExclusionConstraint(BaseConstraint):
     def constraint_sql(self, model, schema_editor):
         query = Query(model, alias_cols=False)
         compiler = query.get_compiler(connection=schema_editor.connection)
-        expressions = self._get_expression_sql(compiler, schema_editor.connection, query)
+        expressions = self._get_expression_sql(compiler, schema_editor, query)
         condition = self._get_condition_sql(compiler, schema_editor, query)
         include = [model._meta.get_field(field_name).column for field_name in self.include]
         return self.template % {
diff --git a/tests/postgres_tests/test_constraints.py b/tests/postgres_tests/test_constraints.py
index 7d79e65239..89463650e8 100644
--- a/tests/postgres_tests/test_constraints.py
+++ b/tests/postgres_tests/test_constraints.py
@@ -7,6 +7,7 @@ from django.db import (
 from django.db.models import (
     CheckConstraint, Deferrable, F, Func, Q, UniqueConstraint,
 )
+from django.db.models.functions import Left
 from django.test import skipUnlessDBFeature
 from django.utils import timezone
 
@@ -608,6 +609,17 @@ class ExclusionConstraintTests(PostgreSQLTestCase):
             editor.remove_constraint(RangesModel, constraint)
         self.assertNotIn(constraint_name, self.get_constraints(RangesModel._meta.db_table))
 
+    def test_expressions_with_params(self):
+        constraint_name = 'scene_left_equal'
+        self.assertNotIn(constraint_name, self.get_constraints(Scene._meta.db_table))
+        constraint = ExclusionConstraint(
+            name=constraint_name,
+            expressions=[(Left('scene', 4), RangeOperators.EQUAL)],
+        )
+        with connection.schema_editor() as editor:
+            editor.add_constraint(Scene, constraint)
+        self.assertIn(constraint_name, self.get_constraints(Scene._meta.db_table))
+
     def test_range_adjacent_initially_deferred(self):
         constraint_name = 'ints_adjacent_deferred'
         self.assertNotIn(constraint_name, self.get_constraints(RangesModel._meta.db_table))