From dbd12228d42b29fb7858dbe3462e1db51fa9658b Mon Sep 17 00:00:00 2001
From: Mike Naberezny <mike@naberezny.com>
Date: Tue, 11 Mar 2014 21:24:41 -0700
Subject: [PATCH] Add tests for INC accumulator on 65C02

---
 py65/tests/devices/test_mpu65c02.py | 32 +++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/py65/tests/devices/test_mpu65c02.py b/py65/tests/devices/test_mpu65c02.py
index cea5b13..dd258ce 100644
--- a/py65/tests/devices/test_mpu65c02.py
+++ b/py65/tests/devices/test_mpu65c02.py
@@ -545,6 +545,38 @@ class MPUTests(unittest.TestCase, Common6502Tests):
         self.assertEqual(mpu.NEGATIVE, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
 
+    # INC Accumulator
+
+    def test_inc_acc_increments_accum(self):
+        mpu = self._make_mpu()
+        mpu.memory[0x0000] = 0x1A
+        mpu.a = 0x42
+        mpu.step()
+        self.assertEqual(0x0001, mpu.pc)
+        self.assertEqual(0x43, mpu.a)
+        self.assertEqual(0, mpu.p & mpu.ZERO)
+        self.assertEqual(0, mpu.p & mpu.NEGATIVE)
+
+    def test_inc_acc_increments_accum_rolls_over_and_sets_zero_flag(self):
+        mpu = self._make_mpu()
+        mpu.memory[0x0000] = 0x1A
+        mpu.a = 0xFF
+        mpu.step()
+        self.assertEqual(0x0001, mpu.pc)
+        self.assertEqual(0x00, mpu.a)
+        self.assertEqual(mpu.ZERO, mpu.p & mpu.ZERO)
+        self.assertEqual(0, mpu.p & mpu.NEGATIVE)
+
+    def test_inc_acc_sets_negative_flag_when_incrementing_above_7F(self):
+        mpu = self._make_mpu()
+        mpu.memory[0x0000] = 0x1A
+        mpu.a = 0x7F
+        mpu.step()
+        self.assertEqual(0x0001, mpu.pc)
+        self.assertEqual(0x80, mpu.a)
+        self.assertEqual(0, mpu.p & mpu.ZERO)
+        self.assertEqual(mpu.NEGATIVE, mpu.p & mpu.NEGATIVE)
+
     # JMP Indirect
 
     def test_jmp_ind_does_not_have_page_wrap_bug(self):