def _detect_fns_free_variables(self,
source_code: str,
imports_and_functions: str = "",
step_parameters: dict = None):
"""Return the function's free variables.
Free variable: _If a variable is used in a code block but not defined
there, it is a free variable._
An Example:
```
x = 5
def foo():
print(x)
```
In the example above, `x` is a free variable for function `foo`,
because it is defined outside of the context of `foo`.
Here we run the PyFlakes report over the function body to get all the
missing names (i.e. free variables), excluding the function arguments.
Args:
source_code: Multiline Python source code
imports_and_functions: Multiline Python source that is prepended
to every pipeline step. It should contain the code cells that
where tagged as `import` and `functions`. We prepend this code
to the function body because it will always be present in any
pipeline step.
step_parameters: Step parameters names. The step parameters
are removed from the pyflakes report, as these names will
always be available in the step's context.
Returns (dict): A dictionary with the name of the function as key and
a list of variables names + consumed pipeline parameters as values.
"""
fns_free_vars = dict()
# now check the functions' bodies for free variables. fns is a
# dict function_name -> function_source
fns = astutils.parse_functions(source_code)
for fn_name, fn in fns.items():
code = imports_and_functions + "\n" + fn
free_vars = flakeutils.pyflakes_report(code=code)
# the pipeline parameters that are used in the function
consumed_params = {}
if step_parameters:
consumed_params = free_vars.intersection(
step_parameters.keys())
# remove the used parameters form the free variables, as they
# need to be handled differently.
free_vars.difference_update(consumed_params)
fns_free_vars[fn_name] = (free_vars, consumed_params)
return fns_free_vars
def test_parse_functions():
"""Test that the body of the function is retrieved correctly."""
code = '''
x = 5
def foo():
print('hello')
print(x)
'''
target = {"foo": "def foo():\n print('hello')\n print(x)\n"}
assert kale_ast.parse_functions(code) == target