2018-02-13 08:40:17 -06:00
|
|
|
use rustc::lint::*;
|
|
|
|
use rustc::hir;
|
|
|
|
use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
|
|
|
|
use syntax::ast;
|
|
|
|
use utils::{get_trait_def_id, span_lint};
|
|
|
|
|
|
|
|
/// **What it does:** Lints for suspicious operations in impls of arithmetic operators, e.g.
|
|
|
|
/// subtracting elements in an Add impl.
|
|
|
|
///
|
|
|
|
/// **Why this is bad?** This is probably a typo or copy-and-paste error and not intended.
|
|
|
|
///
|
|
|
|
/// **Known problems:** None.
|
|
|
|
///
|
|
|
|
/// **Example:**
|
|
|
|
/// ```rust
|
|
|
|
/// impl Add for Foo {
|
|
|
|
/// type Output = Foo;
|
|
|
|
///
|
|
|
|
/// fn add(self, other: Foo) -> Foo {
|
|
|
|
/// Foo(self.0 - other.0)
|
|
|
|
/// }
|
|
|
|
/// }
|
|
|
|
/// ```
|
2018-03-28 08:24:26 -05:00
|
|
|
declare_clippy_lint! {
|
2018-02-13 08:40:17 -06:00
|
|
|
pub SUSPICIOUS_ARITHMETIC_IMPL,
|
2018-03-28 08:24:26 -05:00
|
|
|
correctness,
|
2018-02-13 08:40:17 -06:00
|
|
|
"suspicious use of operators in impl of arithmetic trait"
|
|
|
|
}
|
|
|
|
|
|
|
|
/// **What it does:** Lints for suspicious operations in impls of OpAssign, e.g.
|
|
|
|
/// subtracting elements in an AddAssign impl.
|
|
|
|
///
|
|
|
|
/// **Why this is bad?** This is probably a typo or copy-and-paste error and not intended.
|
|
|
|
///
|
|
|
|
/// **Known problems:** None.
|
|
|
|
///
|
|
|
|
/// **Example:**
|
|
|
|
/// ```rust
|
|
|
|
/// impl AddAssign for Foo {
|
|
|
|
/// fn add_assign(&mut self, other: Foo) {
|
|
|
|
/// *self = *self - other;
|
|
|
|
/// }
|
|
|
|
/// }
|
|
|
|
/// ```
|
2018-03-28 08:24:26 -05:00
|
|
|
declare_clippy_lint! {
|
2018-02-13 08:40:17 -06:00
|
|
|
pub SUSPICIOUS_OP_ASSIGN_IMPL,
|
2018-03-28 08:24:26 -05:00
|
|
|
correctness,
|
2018-02-13 08:40:17 -06:00
|
|
|
"suspicious use of operators in impl of OpAssign trait"
|
|
|
|
}
|
|
|
|
|
|
|
|
#[derive(Copy, Clone)]
|
|
|
|
pub struct SuspiciousImpl;
|
|
|
|
|
|
|
|
impl LintPass for SuspiciousImpl {
|
|
|
|
fn get_lints(&self) -> LintArray {
|
|
|
|
lint_array![SUSPICIOUS_ARITHMETIC_IMPL, SUSPICIOUS_OP_ASSIGN_IMPL]
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for SuspiciousImpl {
|
|
|
|
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
|
|
|
|
use rustc::hir::BinOp_::*;
|
|
|
|
if let hir::ExprBinary(binop, _, _) = expr.node {
|
2018-03-17 15:34:13 -05:00
|
|
|
match binop.node {
|
|
|
|
BiEq | BiLt | BiLe | BiNe | BiGe | BiGt => return,
|
|
|
|
_ => {},
|
|
|
|
}
|
2018-03-06 06:58:03 -06:00
|
|
|
// Check if the binary expression is part of another bi/unary expression
|
2018-02-13 08:40:17 -06:00
|
|
|
// as a child node
|
|
|
|
let mut parent_expr = cx.tcx.hir.get_parent_node(expr.id);
|
|
|
|
while parent_expr != ast::CRATE_NODE_ID {
|
2018-03-06 06:58:03 -06:00
|
|
|
if let hir::map::Node::NodeExpr(e) = cx.tcx.hir.get(parent_expr) {
|
|
|
|
match e.node {
|
|
|
|
hir::ExprBinary(..)
|
|
|
|
| hir::ExprUnary(hir::UnOp::UnNot, _)
|
|
|
|
| hir::ExprUnary(hir::UnOp::UnNeg, _) => return,
|
|
|
|
_ => {},
|
2018-02-13 08:40:17 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
parent_expr = cx.tcx.hir.get_parent_node(parent_expr);
|
|
|
|
}
|
|
|
|
// as a parent node
|
|
|
|
let mut visitor = BinaryExprVisitor {
|
|
|
|
in_binary_expr: false,
|
|
|
|
};
|
|
|
|
walk_expr(&mut visitor, expr);
|
|
|
|
|
|
|
|
if visitor.in_binary_expr {
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
if let Some(impl_trait) = check_binop(
|
|
|
|
cx,
|
|
|
|
expr,
|
|
|
|
&binop.node,
|
|
|
|
&["Add", "Sub", "Mul", "Div"],
|
|
|
|
&[BiAdd, BiSub, BiMul, BiDiv],
|
|
|
|
) {
|
|
|
|
span_lint(
|
|
|
|
cx,
|
|
|
|
SUSPICIOUS_ARITHMETIC_IMPL,
|
|
|
|
binop.span,
|
|
|
|
&format!(
|
|
|
|
r#"Suspicious use of binary operator in `{}` impl"#,
|
|
|
|
impl_trait
|
|
|
|
),
|
|
|
|
);
|
|
|
|
}
|
|
|
|
|
|
|
|
if let Some(impl_trait) = check_binop(
|
|
|
|
cx,
|
|
|
|
expr,
|
|
|
|
&binop.node,
|
|
|
|
&[
|
|
|
|
"AddAssign",
|
|
|
|
"SubAssign",
|
|
|
|
"MulAssign",
|
|
|
|
"DivAssign",
|
|
|
|
"BitAndAssign",
|
|
|
|
"BitOrAssign",
|
|
|
|
"BitXorAssign",
|
|
|
|
"RemAssign",
|
|
|
|
"ShlAssign",
|
|
|
|
"ShrAssign",
|
|
|
|
],
|
|
|
|
&[
|
|
|
|
BiAdd, BiSub, BiMul, BiDiv, BiBitAnd, BiBitOr, BiBitXor, BiRem, BiShl, BiShr
|
|
|
|
],
|
|
|
|
) {
|
|
|
|
span_lint(
|
|
|
|
cx,
|
|
|
|
SUSPICIOUS_OP_ASSIGN_IMPL,
|
|
|
|
binop.span,
|
|
|
|
&format!(
|
|
|
|
r#"Suspicious use of binary operator in `{}` impl"#,
|
|
|
|
impl_trait
|
|
|
|
),
|
|
|
|
);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
fn check_binop<'a>(
|
|
|
|
cx: &LateContext,
|
|
|
|
expr: &hir::Expr,
|
|
|
|
binop: &hir::BinOp_,
|
|
|
|
traits: &[&'a str],
|
|
|
|
expected_ops: &[hir::BinOp_],
|
|
|
|
) -> Option<&'a str> {
|
|
|
|
let mut trait_ids = vec![];
|
|
|
|
let [krate, module] = ::utils::paths::OPS_MODULE;
|
|
|
|
|
|
|
|
for t in traits {
|
|
|
|
let path = [krate, module, t];
|
|
|
|
if let Some(trait_id) = get_trait_def_id(cx, &path) {
|
|
|
|
trait_ids.push(trait_id);
|
|
|
|
} else {
|
|
|
|
return None;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Get the actually implemented trait
|
|
|
|
let parent_fn = cx.tcx.hir.get_parent(expr.id);
|
|
|
|
let parent_impl = cx.tcx.hir.get_parent(parent_fn);
|
|
|
|
|
|
|
|
if_chain! {
|
|
|
|
if parent_impl != ast::CRATE_NODE_ID;
|
|
|
|
if let hir::map::Node::NodeItem(item) = cx.tcx.hir.get(parent_impl);
|
|
|
|
if let hir::Item_::ItemImpl(_, _, _, _, Some(ref trait_ref), _, _) = item.node;
|
|
|
|
if let Some(idx) = trait_ids.iter().position(|&tid| tid == trait_ref.path.def.def_id());
|
|
|
|
if *binop != expected_ops[idx];
|
|
|
|
then{
|
|
|
|
return Some(traits[idx])
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
None
|
|
|
|
}
|
|
|
|
|
|
|
|
struct BinaryExprVisitor {
|
|
|
|
in_binary_expr: bool,
|
|
|
|
}
|
|
|
|
|
|
|
|
impl<'a, 'tcx: 'a> Visitor<'tcx> for BinaryExprVisitor {
|
|
|
|
fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
|
2018-03-06 06:58:03 -06:00
|
|
|
match expr.node {
|
|
|
|
hir::ExprBinary(..)
|
|
|
|
| hir::ExprUnary(hir::UnOp::UnNot, _)
|
|
|
|
| hir::ExprUnary(hir::UnOp::UnNeg, _) => {
|
|
|
|
self.in_binary_expr = true
|
|
|
|
},
|
|
|
|
_ => {},
|
2018-02-13 08:40:17 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
walk_expr(self, expr);
|
|
|
|
}
|
|
|
|
fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
|
|
|
|
NestedVisitorMap::None
|
|
|
|
}
|
|
|
|
}
|