regress: add x86_nasm_directives.py for 'bits' directive for NASM syntax

suite/regress/x86_nasm_directives.py

+#!/usr/bin/python
+# Nguyen Anh Quynh, 2016
+
+# This is to test NASM directives
+
+# Fill in the information in the form below when you create a new regression
+
+# Github issue: #xxx
+# Author: Nguyen Anh Quynh
+
+from keystone import *
+
+import regress
+
+class TestX86(regress.RegressTest):
+    def runTest(self):
+        # Initialize Keystone engine
+        ks = Ks(KS_ARCH_X86, KS_MODE_32)
+        # change the syntax to NASM
+        ks.syntax = KS_OPT_SYNTAX_NASM
+
+        # compile an instruction in NASM syntax
+        #encoding, count = ks.asm(b"bits 32\n add eax, ebx\nbits 16\nadd eax, ebx")
+        encoding, count = ks.asm(b"bits 32\n add eax, ebx\nbits 16\nadd eax, ebx")
+        # Assert the result
+        self.assertEqual(encoding, [ 0x01, 0xd8, 0x66, 0x01, 0xd8 ])
+
+if __name__ == '__main__':
+    regress.main()