gh-154840: Keep the color pair out of curses complexchar.attr

Lib/test/test_curses.py

@@ -584,9 +584,15 @@ def test_in_wch_color(self):
         stdscr.addch(0, 0, curses.complexchar('A', curses.A_BOLD, 1))
         cc = stdscr.in_wch(0, 0)
         self.assertEqual(str(cc), 'A')
-        self.assertTrue(cc.attr & curses.A_BOLD)
+        self.assertEqual(cc.attr, curses.A_BOLD)
         self.assertEqual(cc.pair, 1)
         self.assertEqual(curses.complexchar('A', 0, 1).pair, 1)
+        # attr never carries the color pair, not even a pair that does not fit
+        # in a color_pair() value.
+        self.assertEqual(curses.complexchar('A', 0, 1).attr, 0)
+        self.assertEqual(curses.complexchar('A', 0, 300).attr, 0)
+        self.assertEqual(curses.complexchar('A', curses.A_BOLD, 1).attr,
+                         curses.A_BOLD)
 
     def test_getbkgrnd(self):
         # getbkgrnd() returns the background as a complexchar (getbkgd() can

Modules/_cursesmodule.c

@@ -889,6 +889,7 @@ curses_cell_attr_pair(cursesmodule_state *state, const curses_cell_t *cell,
         PyErr_SetString(state->error, "getcchar() returned ERR");
         return -1;
     }
+    *attr &= ~(attr_t)A_COLOR;
     return 0;
 #else
     *attr = *cell & A_ATTRIBUTES & ~(attr_t)A_COLOR;