added test

Author: gargsaumya

tests/test_004_cursor.py

@@ -15497,6 +15497,88 @@ def test_fixed_length_binary_type(cursor, db_connection):
         pytest.fail(f"Fixed-length BINARY test failed: {e}")
 
 
+def test_fetchall_with_integrity_constraint(cursor, db_connection):
+    """
+    Test that UNIQUE constraint errors are appropriately triggered for multi-row INSERT 
+    statements that use OUTPUT inserted.
+    
+    This test covers a specific case where SQL Server's protocol has error conditions 
+    that do not become apparent until rows are fetched, requiring special handling 
+    in fetchall().
+    """
+    try:
+        # Setup table with unique constraint
+        cursor.execute("DROP TABLE IF EXISTS #uniq_cons_test")
+        cursor.execute("""
+        CREATE TABLE #uniq_cons_test (
+            id INTEGER NOT NULL IDENTITY,
+            data VARCHAR(50) NULL,
+            PRIMARY KEY (id),
+            UNIQUE (data)
+        )
+        """)
+        
+        # Insert initial row - should work
+        cursor.execute("INSERT INTO #uniq_cons_test (data) OUTPUT inserted.id VALUES (?)", ('the data 1',))
+        cursor.fetchall()  # Complete the operation
+        
+        # Test single row duplicate - should raise IntegrityError
+        with pytest.raises(mssql_python.IntegrityError):
+            cursor.execute("INSERT INTO #uniq_cons_test (data) OUTPUT inserted.id VALUES (?)", ('the data 1',))
+            cursor.fetchall()  # Error should be detected here
+        
+        # Insert two valid rows in one statement - should work
+        cursor.execute("INSERT INTO #uniq_cons_test (data) OUTPUT inserted.id VALUES (?), (?)", 
+                      ('the data 2', 'the data 3'))
+        cursor.fetchall()
+        
+        # Verify current state
+        cursor.execute("SELECT * FROM #uniq_cons_test ORDER BY id")
+        rows = cursor.fetchall()
+        expected_before = [(1, "the data 1"), (3, "the data 2"), (4, "the data 3")]
+        actual_before = [tuple(row) for row in rows]
+        assert actual_before == expected_before
+        
+        # THE CRITICAL TEST: Multi-row INSERT with duplicate values
+        # This should raise IntegrityError during fetchall()
+        with pytest.raises(mssql_python.IntegrityError):
+            cursor.execute("INSERT INTO #uniq_cons_test (data) OUTPUT inserted.id VALUES (?), (?)", 
+                          ('the data 4', 'the data 4'))  # Duplicate in same statement
+            
+            # The error should be detected HERE during fetchall()
+            cursor.fetchall()
+        
+        # Verify table state after failed multi-row insert
+        cursor.execute("SELECT * FROM #uniq_cons_test ORDER BY id")
+        rows = cursor.fetchall()
+        expected_after = [(1, "the data 1"), (3, "the data 2"), (4, "the data 3")]
+        actual_after = [tuple(row) for row in rows]
+        assert actual_after == expected_after, "Table should be unchanged after failed insert"
+        
+        # Test timing: execute() should succeed, error detection happens in fetchall()
+        try:
+            cursor.execute("INSERT INTO #uniq_cons_test (data) OUTPUT inserted.id VALUES (?), (?)", 
+                          ('the data 5', 'the data 5'))
+            execute_succeeded = True
+        except Exception:
+            execute_succeeded = False
+        
+        assert execute_succeeded, "execute() should succeed, error detection happens in fetchall()"
+        
+        # fetchall() should raise the IntegrityError
+        with pytest.raises(mssql_python.IntegrityError):
+            cursor.fetchall()
+        
+    except Exception as e:
+        pytest.fail(f"Integrity constraint multi-row test failed: {e}")
+    finally:
+        # Cleanup
+        try:
+            cursor.execute("DROP TABLE IF EXISTS #uniq_cons_test")
+        except:
+            pass
+
+
 def test_close(db_connection):
     """Test closing the cursor"""
     try: