Files
ruff/src/flake8_bugbear/plugins/function_call_argument_default.rs
2022-12-16 22:55:47 -05:00

123 lines
3.7 KiB
Rust

use rustc_hash::{FxHashMap, FxHashSet};
use rustpython_ast::{Arguments, Constant, Expr, ExprKind};
use crate::ast::helpers::{
collect_call_paths, compose_call_path, dealias_call_path, match_call_path, to_module_and_member,
};
use crate::ast::types::Range;
use crate::ast::visitor;
use crate::ast::visitor::Visitor;
use crate::checkers::ast::Checker;
use crate::checks::{Check, CheckKind};
use crate::flake8_bugbear::plugins::mutable_argument_default::is_mutable_func;
const IMMUTABLE_FUNCS: [(&str, &str); 7] = [
("", "tuple"),
("", "frozenset"),
("operator", "attrgetter"),
("operator", "itemgetter"),
("operator", "methodcaller"),
("types", "MappingProxyType"),
("re", "compile"),
];
fn is_immutable_func(
expr: &Expr,
extend_immutable_calls: &[(&str, &str)],
from_imports: &FxHashMap<&str, FxHashSet<&str>>,
import_aliases: &FxHashMap<&str, &str>,
) -> bool {
let call_path = dealias_call_path(collect_call_paths(expr), import_aliases);
IMMUTABLE_FUNCS
.iter()
.chain(extend_immutable_calls)
.any(|(module, member)| match_call_path(&call_path, module, member, from_imports))
}
struct ArgumentDefaultVisitor<'a> {
checks: Vec<(CheckKind, Range)>,
extend_immutable_calls: &'a [(&'a str, &'a str)],
from_imports: &'a FxHashMap<&'a str, FxHashSet<&'a str>>,
import_aliases: &'a FxHashMap<&'a str, &'a str>,
}
impl<'a, 'b> Visitor<'b> for ArgumentDefaultVisitor<'b>
where
'b: 'a,
{
fn visit_expr(&mut self, expr: &'b Expr) {
match &expr.node {
ExprKind::Call { func, args, .. } => {
if !is_mutable_func(func, self.from_imports, self.import_aliases)
&& !is_immutable_func(
func,
self.extend_immutable_calls,
self.from_imports,
self.import_aliases,
)
&& !is_nan_or_infinity(func, args)
{
self.checks.push((
CheckKind::FunctionCallArgumentDefault(compose_call_path(expr)),
Range::from_located(expr),
));
}
visitor::walk_expr(self, expr);
}
ExprKind::Lambda { .. } => {}
_ => visitor::walk_expr(self, expr),
}
}
}
fn is_nan_or_infinity(expr: &Expr, args: &[Expr]) -> bool {
let ExprKind::Name { id, .. } = &expr.node else {
return false;
};
if id != "float" {
return false;
}
let Some(arg) = args.first() else {
return false;
};
let ExprKind::Constant {
value: Constant::Str(value),
..
} = &arg.node else {
return false;
};
let lowercased = value.to_lowercase();
matches!(
lowercased.as_str(),
"nan" | "+nan" | "-nan" | "inf" | "+inf" | "-inf" | "infinity" | "+infinity" | "-infinity"
)
}
/// B008
pub fn function_call_argument_default(checker: &mut Checker, arguments: &Arguments) {
// Map immutable calls to (module, member) format.
let extend_immutable_cells: Vec<(&str, &str)> = checker
.settings
.flake8_bugbear
.extend_immutable_calls
.iter()
.map(|target| to_module_and_member(target))
.collect();
let mut visitor = ArgumentDefaultVisitor {
checks: vec![],
extend_immutable_calls: &extend_immutable_cells,
from_imports: &checker.from_imports,
import_aliases: &checker.import_aliases,
};
for expr in arguments
.defaults
.iter()
.chain(arguments.kw_defaults.iter())
{
visitor.visit_expr(expr);
}
for (check, range) in visitor.checks {
checker.add_check(Check::new(check, range));
}
}