def insert_code(code_to_modify, code_to_insert, before_line):
"""
Insert piece of code `code_to_insert` to `code_to_modify` right inside the line `before_line` before the
instruction on this line by modifying original bytecode
:param code_to_modify: Code to modify
:param code_to_insert: Code to insert
:param before_line: Number of line for code insertion
:return: boolean flag whether insertion was successful, modified code
"""
linestarts = dict(dis.findlinestarts(code_to_modify))
if before_line not in linestarts.values():
return code_to_modify
offset = None
for off, line_no in linestarts.items():
if line_no == before_line:
offset = off
return_none_size = len(_return_none_fun.__code__.co_code)
code_to_insert_obj = code_to_insert.co_code[:-return_none_size]
try:
code_to_insert_obj, new_names = \
_add_attr_values_from_insert_to_original(code_to_modify, code_to_insert, code_to_insert_obj, 'co_names',
dis.hasname)
code_to_insert_obj, new_consts = \
_add_attr_values_from_insert_to_original(code_to_modify, code_to_insert, code_to_insert_obj, 'co_consts',
[opmap['LOAD_CONST']])
code_to_insert_obj, new_vars = \
_add_attr_values_from_insert_to_original(code_to_modify, code_to_insert, code_to_insert_obj, 'co_varnames',
dis.haslocal)
new_bytes, all_inserted_code = _update_label_offsets(code_to_modify.co_code, offset, list(code_to_insert_obj))
new_lnotab = _modify_new_lines(code_to_modify, all_inserted_code)
except ValueError:
traceback.print_exc()
return False, code_to_modify
new_code = CodeType(
code_to_modify.co_argcount, # integer
code_to_modify.co_kwonlyargcount, # integer
len(new_vars), # integer
code_to_modify.co_stacksize, # integer
code_to_modify.co_flags, # integer
new_bytes, # bytes
new_consts, # tuple
new_names, # tuple
new_vars, # tuple
code_to_modify.co_filename, # string
code_to_modify.co_name, # string
code_to_modify.co_firstlineno, # integer
new_lnotab, # bytes
code_to_modify.co_freevars, # tuple
code_to_modify.co_cellvars # tuple
)
return True, new_code
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