📁 /snap/core22/2955/lib/python3.10/test/support/bytecode_helper.py
"""bytecode_helper - support tools for testing correct bytecode generation"""
import unittest
import dis
import io
_UNSPECIFIED = object()
class BytecodeTestCase(unittest.TestCase):
"""Custom assertion methods for inspecting bytecode."""
def get_disassembly_as_string(self, co):
s = io.StringIO()
dis.dis(co, file=s)
return s.getvalue()
def assertInBytecode(self, x, opname, argval=_UNSPECIFIED):
"""Returns instr if opname is found, otherwise throws AssertionError"""
for instr in dis.get_instructions(x):
if instr.opname == opname:
if argval is _UNSPECIFIED or instr.argval == argval:
return instr
disassembly = self.get_disassembly_as_string(x)
if argval is _UNSPECIFIED:
msg = '%s not found in bytecode:\n%s' % (opname, disassembly)
else:
msg = '(%s,%r) not found in bytecode:\n%s'
msg = msg % (opname, argval, disassembly)
self.fail(msg)
def assertNotInBytecode(self, x, opname, argval=_UNSPECIFIED):
"""Throws AssertionError if opname is found"""
for instr in dis.get_instructions(x):
if instr.opname == opname:
disassembly = self.get_disassembly_as_string(x)
if argval is _UNSPECIFIED:
msg = '%s occurs in bytecode:\n%s' % (opname, disassembly)
self.fail(msg)
elif instr.argval == argval:
msg = '(%s,%r) occurs in bytecode:\n%s'
msg = msg % (opname, argval, disassembly)
self.fail(msg)