"""Fixer for operator functions.

operator.isCallable(obj) -> hasattr(obj, '__call__')
operator.sequenceIncludes(obj) -> operator.contains(obj)
operator.isSequenceType(obj) -> isinstance(obj, collections.Sequence)
operator.isMappingType(obj) -> isinstance(obj, collections.Mapping)
operator.isNumberType(obj) -> isinstance(obj, numbers.Number)
operator.repeat(obj, n) -> operator.mul(obj, n)
operator.irepeat(obj, n) -> operator.imul(obj, n)
"""

import collections

# Local imports
from lib2to3 import fixer_base
from lib2to3.fixer_util import Call, Name, String, touch_import


def invocation(s):
def dec(f):
f.invocation = s
return f
return dec


class FixOperator(fixer_base.BaseFix):
BM_compatible = True
order = "pre"

methods = """
method=('isCallable'|'sequenceIncludes'
|'isSequenceType'|'isMappingType'|'isNumberType'
|'repeat'|'irepeat')
"""
obj = "'(' obj=any ')'"
PATTERN = """
power< module='operator'
trailer< '.' %(methods)s > trailer< %(obj)s > >
|
power< %(methods)s trailer< %(obj)s > >
""" % dict(methods=methods, obj=obj)

def transform(self, node, results):
method = self._check_method(node, results)
if method is not None:
return method(node, results)

@invocation("operator.contains(%s)")
def _sequenceIncludes(self, node, results):
return self._handle_rename(node, results, "contains")

@invocation("hasattr(%s, '__call__')")
def _isCallable(self, node, results):
obj = results["obj"]
args = [obj.clone(), String(", "), String("'__call__'")]
return Call(Name("hasattr"), args, prefix=node.prefix)

@invocation("operator.mul(%s)")
def _repeat(self, node, results):
return self._handle_rename(node, results, "mul")

@invocation("operator.imul(%s)")
def _irepeat(self, node, results):
return self._handle_rename(node, results, "imul")

@invocation("isinstance(%s, collections.Sequence)")
def _isSequenceType(self, node, results):
return self._handle_type2abc(node, results, "collections", "Sequence")

@invocation("isinstance(%s, collections.Mapping)")
def _isMappingType(self, node, results):
return self._handle_type2abc(node, results, "collections", "Mapping")

@invocation("isinstance(%s, numbers.Number)")
def _isNumberType(self, node, results):
return self._handle_type2abc(node, results, "numbers", "Number")

def _handle_rename(self, node, results, name):
method = results["method"][0]
method.value = name
method.changed()

def _handle_type2abc(self, node, results, module, abc):
touch_import(None, module, node)
obj = results["obj"]
args = [obj.clone(), String(", " + ".".join([module, abc]))]
return Call(Name("isinstance"), args, prefix=node.prefix)

def _check_method(self, node, results):
method = getattr(self, "_" + results["method"][0].value)
if isinstance(method, collections.Callable):
if "module" in results:
return method
else:
sub = (str(results["obj"]),)
invocation_str = method.invocation % sub
self.warning(node, "You should use '%s' here." % invocation_str)
return None