-use if_chain::if_chain;
-use rustc::hir;
-use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc::{declare_lint_pass, declare_tool_lint};
-use rustc_errors::Applicability;
-
use crate::utils::{
- get_trait_def_id, implements_trait, snippet_opt, span_lint_and_then, trait_ref_of_method, SpanlessEq,
+ eq_expr_value, get_trait_def_id, implements_trait, snippet_opt, span_lint_and_then, trait_ref_of_method,
};
use crate::utils::{higher, sugg};
-use syntax::symbol::Symbol;
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::hir::map::Map;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
declare_clippy_lint! {
/// **What it does:** Checks for `a = a op b` or `a = b commutative_op a`
/// let mut a = 5;
/// let b = 0;
/// // ...
+ /// // Bad
/// a = a + b;
+ ///
+ /// // Good
+ /// a += b;
/// ```
pub ASSIGN_OP_PATTERN,
style,
/// **Example:**
/// ```rust
/// let mut a = 5;
- /// ...
+ /// let b = 2;
+ /// // ...
/// a += a + b;
/// ```
pub MISREFACTORED_ASSIGN_OP,
declare_lint_pass!(AssignOps => [ASSIGN_OP_PATTERN, MISREFACTORED_ASSIGN_OP]);
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for AssignOps {
+impl<'tcx> LateLintPass<'tcx> for AssignOps {
#[allow(clippy::too_many_lines)]
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
- match &expr.node {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+ match &expr.kind {
hir::ExprKind::AssignOp(op, lhs, rhs) => {
- if let hir::ExprKind::Binary(binop, l, r) = &rhs.node {
+ if let hir::ExprKind::Binary(binop, l, r) = &rhs.kind {
if op.node != binop.node {
return;
}
// lhs op= l op r
- if SpanlessEq::new(cx).ignore_fn().eq_expr(lhs, l) {
+ if eq_expr_value(cx, lhs, l) {
lint_misrefactored_assign_op(cx, expr, *op, rhs, lhs, r);
}
// lhs op= l commutative_op r
- if is_commutative(op.node) && SpanlessEq::new(cx).ignore_fn().eq_expr(lhs, r) {
+ if is_commutative(op.node) && eq_expr_value(cx, lhs, r) {
lint_misrefactored_assign_op(cx, expr, *op, rhs, lhs, l);
}
}
},
- hir::ExprKind::Assign(assignee, e) => {
- if let hir::ExprKind::Binary(op, l, r) = &e.node {
- #[allow(clippy::cognitive_complexity)]
- let lint = |assignee: &hir::Expr, rhs: &hir::Expr| {
- let ty = cx.tables.expr_ty(assignee);
- let rty = cx.tables.expr_ty(rhs);
+ hir::ExprKind::Assign(assignee, e, _) => {
+ if let hir::ExprKind::Binary(op, l, r) = &e.kind {
+ let lint = |assignee: &hir::Expr<'_>, rhs: &hir::Expr<'_>| {
+ let ty = cx.typeck_results().expr_ty(assignee);
+ let rty = cx.typeck_results().expr_ty(rhs);
macro_rules! ops {
($op:expr,
$cx:expr,
$($trait_name:ident),+) => {
match $op {
$(hir::BinOpKind::$trait_name => {
- let [krate, module] = *crate::utils::paths::OPS_MODULE;
- let ident = {
- *crate::utils::sym::assign::$trait_name
- };
- let path: [Symbol; 3] = [krate, module, ident];
+ let [krate, module] = crate::utils::paths::OPS_MODULE;
+ let path: [&str; 3] = [krate, module, concat!(stringify!($trait_name), "Assign")];
let trait_id = if let Some(trait_id) = get_trait_def_id($cx, &path) {
trait_id
} else {
ASSIGN_OP_PATTERN,
expr.span,
"manual implementation of an assign operation",
- |db| {
+ |diag| {
if let (Some(snip_a), Some(snip_r)) =
(snippet_opt(cx, assignee.span), snippet_opt(cx, rhs.span))
{
- db.span_suggestion(
+ diag.span_suggestion(
expr.span,
"replace it with",
format!("{} {}= {}", snip_a, op.node.as_str(), snip_r),
if visitor.counter == 1 {
// a = a op b
- if SpanlessEq::new(cx).ignore_fn().eq_expr(assignee, l) {
+ if eq_expr_value(cx, assignee, l) {
lint(assignee, r);
}
// a = b commutative_op a
// Limited to primitive type as these ops are know to be commutative
- if SpanlessEq::new(cx).ignore_fn().eq_expr(assignee, r)
- && cx.tables.expr_ty(assignee).is_primitive_ty()
- {
+ if eq_expr_value(cx, assignee, r) && cx.typeck_results().expr_ty(assignee).is_primitive_ty() {
match op.node {
hir::BinOpKind::Add
| hir::BinOpKind::Mul
}
fn lint_misrefactored_assign_op(
- cx: &LateContext<'_, '_>,
- expr: &hir::Expr,
+ cx: &LateContext<'_>,
+ expr: &hir::Expr<'_>,
op: hir::BinOp,
- rhs: &hir::Expr,
- assignee: &hir::Expr,
- rhs_other: &hir::Expr,
+ rhs: &hir::Expr<'_>,
+ assignee: &hir::Expr<'_>,
+ rhs_other: &hir::Expr<'_>,
) {
span_lint_and_then(
cx,
MISREFACTORED_ASSIGN_OP,
expr.span,
"variable appears on both sides of an assignment operation",
- |db| {
+ |diag| {
if let (Some(snip_a), Some(snip_r)) = (snippet_opt(cx, assignee.span), snippet_opt(cx, rhs_other.span)) {
let a = &sugg::Sugg::hir(cx, assignee, "..");
let r = &sugg::Sugg::hir(cx, rhs, "..");
let long = format!("{} = {}", snip_a, sugg::make_binop(higher::binop(op.node), a, r));
- db.span_suggestion(
+ diag.span_suggestion(
expr.span,
&format!(
- "Did you mean {} = {} {} {} or {}? Consider replacing it with",
+ "did you mean `{} = {} {} {}` or `{}`? Consider replacing it with",
snip_a,
snip_a,
op.node.as_str(),
long
),
format!("{} {}= {}", snip_a, op.node.as_str(), snip_r),
- Applicability::MachineApplicable,
+ Applicability::MaybeIncorrect,
);
- db.span_suggestion(
+ diag.span_suggestion(
expr.span,
"or",
long,
- Applicability::MachineApplicable, // snippet
+ Applicability::MaybeIncorrect, // snippet
);
}
},
);
}
+#[must_use]
fn is_commutative(op: hir::BinOpKind) -> bool {
- use rustc::hir::BinOpKind::*;
+ use rustc_hir::BinOpKind::{
+ Add, And, BitAnd, BitOr, BitXor, Div, Eq, Ge, Gt, Le, Lt, Mul, Ne, Or, Rem, Shl, Shr, Sub,
+ };
match op {
Add | Mul | And | Or | BitXor | BitAnd | BitOr | Eq | Ne => true,
Sub | Div | Rem | Shl | Shr | Lt | Le | Ge | Gt => false,
}
}
-struct ExprVisitor<'a, 'tcx: 'a> {
- assignee: &'a hir::Expr,
+struct ExprVisitor<'a, 'tcx> {
+ assignee: &'a hir::Expr<'a>,
counter: u8,
- cx: &'a LateContext<'a, 'tcx>,
+ cx: &'a LateContext<'tcx>,
}
-impl<'a, 'tcx: 'a> Visitor<'tcx> for ExprVisitor<'a, 'tcx> {
- fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
- if SpanlessEq::new(self.cx).ignore_fn().eq_expr(self.assignee, expr) {
+impl<'a, 'tcx> Visitor<'tcx> for ExprVisitor<'a, 'tcx> {
+ type Map = Map<'tcx>;
+
+ fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
+ if eq_expr_value(self.cx, self.assignee, expr) {
self.counter += 1;
}
walk_expr(self, expr);
}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
NestedVisitorMap::None
}
}