ReplaceFunc

Replace functions in the function to decorate

(It is better to use unittest.mock.patch() than to use this replaceFunc().)

Deployment

install replacefunc.py into PYTHONPATH.

Usage Example

from replacefunc import replaceFunc

def newFunc(arg):  # new function
    print("{} printed by the new function.".format(arg)) 
    
def newFunc2(arg):  # new function2
    print("{} printed by the new function2.".format(arg))
    
@replaceFunc(print=newFunc, len=newFunc2)  # old function = new function
def targetFunc():  # Replace functions in this function
    print("arg in the taget function")
    len("arg in the taget function2")
    
targetFunc()  # Call the decorated function

targetFunc() is rewritten by replaceFunc() as follows.

def targetFunc():  # Replace functions in this function
    #replace functions
    len = newFunc2
    print = newFunc
    print("arg in the taget function")
    len("arg in the taget function2")

Adding keyword arguments allows you to output the edited code.

targetFunc = replaceFunc(print=newFunc, len=newFunc2)(targetFunc, debug=True)
targetFunc()

Disadvantage

Breakpoint can not be set in the edited code.

Release Note

v2.0.0 When the value of the keyword argument is a string, the string in the function code of the argument is replaced　with the string.

v2.2.0 Changed to get bytecode and return it. This invalidates __wraped__ in functools.wrap.