Add test that fails when disassembling wraps around memory

py65/tests/test_disassembler.py

@@ -7,6 +7,17 @@ from py65.utils.addressing import AddressParser
 
 
 class DisassemblerTests(unittest.TestCase):
+    def test_disassemble_wraps_after_top_of_mem(self):
+        mpu = MPU()
+        mpu.memory[0xFFFF] = 0x20  # JSR
+        mpu.memory[0x0000] = 0xD2  #
+        mpu.memory[0x0001] = 0xFF  # $FFD2
+
+        dis = Disassembler(mpu)
+        length, disasm = dis.instruction_at(0xFFFF)
+        self.assertEqual(3, length)
+        self.assertEqual('JSR $ffd2', disasm)
+
     def test_disassembles_00(self):
         length, disasm = self.disassemble([0x00])
         self.assertEqual(1, length)