def trace_function(self, func):
# type: (FunctionType) -> FunctionType
"""
Returns a version of the passed function with the AST modified to
trigger the tracing hooks.
"""
if not isinstance(func, FunctionType):
raise ValueError('You can only trace user-defined functions. '
'The birdseye decorator must be applied first, '
'at the bottom of the list.')
try:
if inspect.iscoroutinefunction(func) or inspect.isasyncgenfunction(
func):
raise ValueError('You cannot trace async functions')
except AttributeError:
pass
if is_lambda(func):
raise ValueError('You cannot trace lambdas')
filename = inspect.getsourcefile(func) # type: str
if is_ipython_cell(filename):
# noinspection PyPackageRequirements
from IPython import get_ipython
import linecache
flags = get_ipython().compile.flags
source = ''.join(linecache.cache[filename][2])
else:
source = read_source_file(filename)
flags = 0
# We compile the entire file instead of just the function source
# because it can contain context which affects the function code,
# e.g. enclosing functions and classes or __future__ imports
traced_file = self.compile(source, filename, flags)
if func.__dict__:
raise ValueError('The birdseye decorator must be applied first, '
'at the bottom of the list.')
# Then we have to recursively search through the newly compiled
# code to find the code we actually want corresponding to this function
code_options = [] # type: List[CodeType]
def find_code(root_code):
# type: (CodeType) -> None
for const in root_code.co_consts: # type: CodeType
if not inspect.iscode(const):
continue
matches = (const.co_firstlineno == func.__code__.co_firstlineno
and const.co_name == func.__code__.co_name)
if matches:
code_options.append(const)
find_code(const)
find_code(traced_file.code)
if len(code_options) > 1:
# Currently lambdas aren't allowed anyway, but should be in the future
assert is_lambda(func)
raise ValueError(
"Failed to trace lambda. Convert the function to a def.")
new_func_code = code_options[0] # type: CodeType
# Give the new function access to the hooks
# We have to use the original __globals__ and not a copy
# because it's the actual module namespace that may get updated by other code
func.__globals__.update(self._trace_methods_dict(traced_file))
# http://stackoverflow.com/a/13503277/2482744
# noinspection PyArgumentList
new_func = FunctionType(new_func_code, func.__globals__, func.__name__,
func.__defaults__, func.__closure__)
update_wrapper(new_func, func) # type: FunctionType
if PY3:
new_func.__kwdefaults__ = getattr(func, '__kwdefaults__', None)
new_func.traced_file = traced_file
return new_func
def test_is_lambda(self):
self.assertTrue(is_lambda(lambda: 0))
self.assertTrue(is_lambda(lambda x, y: x + y))
self.assertFalse(is_lambda(min))
self.assertFalse(is_lambda(flatten_list))
self.assertFalse(is_lambda(self.test_is_lambda))
