def main(vmfile):
vmparser = VMParser(vmfile)
cw = CodeWriter()
while True:
vmparser.advance()
cw.process_command(vmparser.command)
if not vmparser.has_more_commands():
break
class TestCodeWriter(TestCase):
def setUp(self):
self.cw = CodeWriter()
def process_commands(self, commands):
for _ in commands:
command = VMCommand(_)
command.parse_command()
self.cw.process_command(command)
def test_write_push_constant(self):
""" test push constant [0-9]* """
# need to update SP, ie RAM[0]
asm_command = ['@7', 'D=A', '@SP', 'A=M', 'M=D', '@SP', 'M=M+1']
commands = ['push constant 7']
self.process_commands(commands)
self.assertListEqual(asm_command, self.cw.assm)
def test_write_two_push_constant(self):
""" push contant [0-9]* twice in a row"""
asm_command = ['@7', 'D=A', '@SP', 'A=M', 'M=D', '@SP', 'M=M+1']
command = VMCommand('push constant 7')
command.parse_command()
self.cw.process_command(command)
self.assertEqual(asm_command, self.cw.assm)
command = VMCommand('push constant 8')
command.parse_command()
self.cw.process_command(command)
asm_command = ['@8', 'D=A', '@SP', 'A=M', 'M=D', '@SP', 'M=M+1']
self.assertEqual(asm_command, self.cw.assm)
def test_write_add_command(self):
"""
test popping top two items off of stack, adding them, and putting
the result back on the stack
"""
# put 7 & 8 on the stack to add
commands = ['push constant 7', 'push constant 8', 'add']
self.process_commands(commands);
assm_command = ['@SP', 'A=M-1', 'D=M', '@SP', 'M=M-1', '@SP', 'A=M-1',
'M=M+D']
self.assertListEqual(assm_command, self.cw.assm)
def test_write_arithmetic_eq(self):
""" test eq """
commands = ['push constant 20', 'push constant 20', 'eq']
self.process_commands(commands)
assm_command = ['@SP', 'A=M-1', 'D=M', '@SP', 'M=M-1', '@SP', 'A=M-1',
'D=M-D', '@SP', 'M=M-1', '@L%s' % 0, 'D;JEQ', '@L%s' % 1,
'(L%s)' % 1, '@SP', 'A=M', 'M=0', '@L%s' % 2, '0;JMP', '(L%s)' %
0, '@SP', 'A=M', 'M=-1', '@L%s' % 2, '0;JMP', '(L%s)' % 2,
'@SP', 'M=M+1']
self.assertListEqual(assm_command, self.cw.assm)
def test_neg(self):
""" test taking negative of top item on stack """
commands = ['push constant 10']
self.process_commands(commands)
command = VMCommand('neg')
command.parse_command()
self.cw.process_command(command)
assm_command = ['@SP', 'A=M-1', 'MD=-M']
self.assertListEqual(assm_command, self.cw.assm)
def test_pop_to_diff_stack(self):
""" test popping to segment. 0 arg2 """
# push ten onto global stack
commands=['push constant 10',
'pop local 0' ]
self.process_commands(commands)
# pop it off and it goes into local
assm_command = ['@LCL', 'D=M', '@0', 'D=A+D', '@R5', 'M=D', '@SP',
'A=M-1', 'D=M', '@R5', 'A=M', 'M=D', '@SP', 'M=M-1']
self.assertListEqual(assm_command, self.cw.assm)
def test_pop_non0_to_diff_stack(self):
""" test pushing to segment. non 0 arg2 """
# push ten onto global stack
commands = ['push constant 10',
'pop local 8']
self.process_commands(commands)
assm_command = ['@LCL', 'D=M', '@8', 'D=A+D', '@R5', 'M=D', '@SP',
'A=M-1', 'D=M', '@R5', 'A=M', 'M=D', '@SP', 'M=M-1']
self.assertListEqual(assm_command, self.cw.assm)
def test_pop_from_segment(self):
""" test pushing from segment onto """
prep_commands=['push constant 12',
'pop local 1',
'push constant 21']
for _ in prep_commands:
command = VMCommand(_)
command.parse_command()
command = VMCommand('push local 1')
command.parse_command()
self.cw.process_command(command)
assm_command = ['@LCL', 'D=M', '@1', 'A=A+D', 'D=M', '@SP', 'A=M',
'M=D', '@SP', 'M=M+1']
self.assertListEqual(assm_command, self.cw.assm)
def test_pop_from_temp(self):
""" test popping from TMP segment """
prep_commands = ['push constant 510']
for _ in prep_commands:
command = VMCommand(_)
command.parse_command()
self.cw.process_command(command)
command = VMCommand('pop temp 6')
command.parse_command()
self.cw.process_command(command)
assm_command = ['@SP', 'A=M-1', 'D=M', '@11', 'M=D', '@SP', 'M=M-1']
self.assertListEqual(assm_command, self.cw.assm)
def test_push_from_temp(self):
""" test pushing from TMP segment """
prep_commands = ['push constant 510',
'pop temp 6',
'push constant 415']
for _ in prep_commands:
command = VMCommand(_)
command.parse_command()
self.cw.process_command(command)
command = VMCommand('push temp 6')
command.parse_command()
self.cw.process_command(command)
assm_command = ['@11', 'D=M', '@SP', 'A=M', 'M=D', '@SP', 'M=M+1']
self.assertListEqual(assm_command, self.cw.assm)
def test_push_from_segment(self):
""" test pushing from segment onto global stack """
commands = ['push constant 510',
'pop local 6',
'push local 6']
self.process_commands(commands)
assm_command = ['@LCL', 'D=M', '@6', 'A=A+D', 'D=M', '@SP', 'A=M',
'M=D', '@SP', 'M=M+1']
self.assertListEqual(assm_command, self.cw.assm)
def test_pop_from_pointer(self):
""" test popping to pointer """
commands = ['push constant 3040', 'pop pointer 0']
self.process_commands(commands)
assm_command = ['@SP', 'A=M-1', 'D=M', '@3', 'M=D', '@SP', 'M=M-1']
self.assertListEqual(assm_command, self.cw.assm)
def test_push_from_pointer(self):
""" test pushing to pointer """
commands = ['push constant 3040', 'pop pointer 0', 'push pointer 0']
self.process_commands(commands)
assm_command = ['@3', 'D=M', '@SP', 'A=M', 'M=D', '@SP', 'M=M+1']
self.assertListEqual(assm_command, self.cw.assm)
