def test_smoke(self):
ctx = Py27EmitterContext().emit_fragment(Return(Add(Load(0), Load(1))))
self.assertEqual(
ctx.last_builder.buf.tolist(),
[124, 0, 0, 124, 1, 0, 23, 83])
self.assertEqual(
ctx.last_builder.stack_changes,
[dec_inc(-0, +1), dec_inc(-0, +1), dec_inc(-2, +1), dec_inc(-1, 0)])
self.assertEqual(ctx.last_builder.stack_usage(), (0, 0, 2))
self.assertTrue(ctx.last_builder.is_valid_stack(), True)
def test_Sub(self):
ctx = Py27EmitterContext().emit_fragment(Subtract())
# XXX: this should not be allowed in practice
self.assertEqual(ctx.last_builder.buf.tolist(), [24])
self.assertEqual(ctx.last_builder.stack_changes, [dec_inc(-2, +1)])
self.assertEqual(ctx.last_builder.stack_usage(), (-2, -1, 0))
self.assertFalse(ctx.last_builder.is_valid_stack())
class UNARY_NEGATIVE(Py27Op):
"""Negate the topmost item on the stack."""
stack = common.dec_inc(-1, +1)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
ctx.stack.append(Neg(ctx.stack.pop()))
class RETURN_VALUE(Py27Op):
"""Pop one value and return it."""
stack = common.dec_inc(-1, +0)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
result = Return(ctx.stack.pop())
ctx.retval = result
ctx.ops.append(result)
class BINARY_MULTIPLY(Py27Op):
"""Multiply two topmost arguments from the stack."""
stack = common.dec_inc(-2, +1)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
b = ctx.stack.pop()
a = ctx.stack.pop()
result = Multiply(a, b)
ctx.stack.append(result)
class BINARY_SUBTRACT(Py27Op):
"""Subtract two topmost arguments from the stack."""
stack = common.dec_inc(-2, +1)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
b = ctx.stack.pop()
a = ctx.stack.pop()
result = Subtract(a, b)
ctx.stack.append(result)
class LOAD_FAST(Py27Op):
"""Load local variable onto the stack."""
has_arg = True
stack = common.dec_inc(-0, +1)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
varname = ctx.varnames[op_arg]
result = Load(varname)
ctx.stack.append(result)
class LOAD_CONST(Py27Op):
"""Load a constant onto the stack."""
has_arg = True
stack = common.dec_inc(-0, +1)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
value = ctx.consts[op_arg]
result = Const(value)
ctx.stack.append(result)
class STORE_FAST(Py27Op):
"""Store a value from the stack into a local variable."""
has_arg = True
stack = common.dec_inc(-1, +0)
@classmethod
def simulate(cls, ctx, op_arg):
"""Simulate execution of the operation."""
varname = ctx.varnames[op_arg]
value = ctx.stack.pop()
result = Store(varname, value)
ctx.locals[op_arg] = result
ctx.ops.append(result)
def test_Return(self):
ctx = Py27EmitterContext().emit_fragment(Return())
self.assertEqual(ctx.last_builder.buf.tolist(), [83])
self.assertEqual(ctx.last_builder.stack_changes, [dec_inc(-1, +0)])
self.assertEqual(ctx.last_builder.stack_usage(), (-1, -1, 0))
self.assertFalse(ctx.last_builder.is_valid_stack())
