boolをそのまま返せばいいのを検出するやつ

detect_useless_if.py

import sys
import ast

class TrueFalseDetected(Exception):
    def __init__(self, lineno, col):
        self.lineno = lineno
        self.col = col

    def __str__(self):
        return 'Useless `if` detected at line {}, column {}'.format(self.lineno, self.col)

class CondTrueFalseDetector(ast.NodeVisitor):
    def visit_IfExp(self, node):
        if isinstance(node.body, ast.NameConstant) and isinstance(node.body.value, bool) and isinstance(node.orelse, ast.NameConstant) and isinstance(node.orelse.value, bool):
            raise TrueFalseDetected(node.lineno, node.col_offset)
        self.visit(node.test)
        self.visit(node.body)
        self.visit(node.orelse)

    def visit_If(self, node):
        if isinstance(node.body[0], ast.Return) and isinstance(node.body[0].value, ast.NameConstant) and isinstance(node.body[0].value.value, bool) and isinstance(node.orelse[0], ast.Return) and isinstance(node.orelse[0].value, ast.NameConstant) and isinstance(node.orelse[0].value.value, bool):
            raise TrueFalseDetected(node.lineno, node.col_offset)
        self.visit(node.test)
        for n in node.body:
            self.visit(n)
        for n in node.orelse:
            self.visit(n)

filename = sys.argv[1]

with open(filename) as f:
    source = f.read()

tree = ast.parse(source, filename)
CondTrueFalseDetector().visit(tree)

print('OK')