-use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg};
+use clippy_utils::diagnostics::{span_lint_hir, span_lint_hir_and_then};
use clippy_utils::source::snippet_opt;
use clippy_utils::ty::has_drop;
use rustc_errors::Applicability;
match expr.kind {
ExprKind::Lit(..) | ExprKind::Closure(..) => true,
ExprKind::Path(..) => !has_drop(cx, cx.typeck_results().expr_ty(expr)),
- ExprKind::Index(ref a, ref b) | ExprKind::Binary(_, ref a, ref b) => {
- has_no_effect(cx, a) && has_no_effect(cx, b)
- },
- ExprKind::Array(ref v) | ExprKind::Tup(ref v) => v.iter().all(|val| has_no_effect(cx, val)),
- ExprKind::Repeat(ref inner, _)
- | ExprKind::Cast(ref inner, _)
- | ExprKind::Type(ref inner, _)
- | ExprKind::Unary(_, ref inner)
- | ExprKind::Field(ref inner, _)
- | ExprKind::AddrOf(_, _, ref inner)
- | ExprKind::Box(ref inner) => has_no_effect(cx, inner),
- ExprKind::Struct(_, ref fields, ref base) => {
+ ExprKind::Index(a, b) | ExprKind::Binary(_, a, b) => has_no_effect(cx, a) && has_no_effect(cx, b),
+ ExprKind::Array(v) | ExprKind::Tup(v) => v.iter().all(|val| has_no_effect(cx, val)),
+ ExprKind::Repeat(inner, _)
+ | ExprKind::Cast(inner, _)
+ | ExprKind::Type(inner, _)
+ | ExprKind::Unary(_, inner)
+ | ExprKind::Field(inner, _)
+ | ExprKind::AddrOf(_, _, inner)
+ | ExprKind::Box(inner) => has_no_effect(cx, inner),
+ ExprKind::Struct(_, fields, ref base) => {
!has_drop(cx, cx.typeck_results().expr_ty(expr))
- && fields.iter().all(|field| has_no_effect(cx, &field.expr))
+ && fields.iter().all(|field| has_no_effect(cx, field.expr))
&& base.as_ref().map_or(true, |base| has_no_effect(cx, base))
},
- ExprKind::Call(ref callee, ref args) => {
+ ExprKind::Call(callee, args) => {
if let ExprKind::Path(ref qpath) = callee.kind {
let res = cx.qpath_res(qpath, callee.hir_id);
match res {
false
}
},
- ExprKind::Block(ref block, _) => {
+ ExprKind::Block(block, _) => {
block.stmts.is_empty() && block.expr.as_ref().map_or(false, |expr| has_no_effect(cx, expr))
},
_ => false,
impl<'tcx> LateLintPass<'tcx> for NoEffect {
fn check_stmt(&mut self, cx: &LateContext<'tcx>, stmt: &'tcx Stmt<'_>) {
- if let StmtKind::Semi(ref expr) = stmt.kind {
+ if let StmtKind::Semi(expr) = stmt.kind {
if has_no_effect(cx, expr) {
- span_lint(cx, NO_EFFECT, stmt.span, "statement with no effect");
+ span_lint_hir(cx, NO_EFFECT, expr.hir_id, stmt.span, "statement with no effect");
} else if let Some(reduced) = reduce_expression(cx, expr) {
let mut snippet = String::new();
for e in reduced {
return;
}
}
- span_lint_and_sugg(
+ span_lint_hir_and_then(
cx,
UNNECESSARY_OPERATION,
+ expr.hir_id,
stmt.span,
"statement can be reduced",
- "replace it with",
- snippet,
- Applicability::MachineApplicable,
+ |diag| {
+ diag.span_suggestion(stmt.span, "replace it with", snippet, Applicability::MachineApplicable);
+ },
);
}
}
return None;
}
match expr.kind {
- ExprKind::Index(ref a, ref b) => Some(vec![&**a, &**b]),
- ExprKind::Binary(ref binop, ref a, ref b) if binop.node != BinOpKind::And && binop.node != BinOpKind::Or => {
- Some(vec![&**a, &**b])
+ ExprKind::Index(a, b) => Some(vec![a, b]),
+ ExprKind::Binary(ref binop, a, b) if binop.node != BinOpKind::And && binop.node != BinOpKind::Or => {
+ Some(vec![a, b])
},
- ExprKind::Array(ref v) | ExprKind::Tup(ref v) => Some(v.iter().collect()),
- ExprKind::Repeat(ref inner, _)
- | ExprKind::Cast(ref inner, _)
- | ExprKind::Type(ref inner, _)
- | ExprKind::Unary(_, ref inner)
- | ExprKind::Field(ref inner, _)
- | ExprKind::AddrOf(_, _, ref inner)
- | ExprKind::Box(ref inner) => reduce_expression(cx, inner).or_else(|| Some(vec![inner])),
- ExprKind::Struct(_, ref fields, ref base) => {
+ ExprKind::Array(v) | ExprKind::Tup(v) => Some(v.iter().collect()),
+ ExprKind::Repeat(inner, _)
+ | ExprKind::Cast(inner, _)
+ | ExprKind::Type(inner, _)
+ | ExprKind::Unary(_, inner)
+ | ExprKind::Field(inner, _)
+ | ExprKind::AddrOf(_, _, inner)
+ | ExprKind::Box(inner) => reduce_expression(cx, inner).or_else(|| Some(vec![inner])),
+ ExprKind::Struct(_, fields, ref base) => {
if has_drop(cx, cx.typeck_results().expr_ty(expr)) {
None
} else {
Some(fields.iter().map(|f| &f.expr).chain(base).map(Deref::deref).collect())
}
},
- ExprKind::Call(ref callee, ref args) => {
+ ExprKind::Call(callee, args) => {
if let ExprKind::Path(ref qpath) = callee.kind {
let res = cx.qpath_res(qpath, callee.hir_id);
match res {
None
}
},
- ExprKind::Block(ref block, _) => {
+ ExprKind::Block(block, _) => {
if block.stmts.is_empty() {
block.expr.as_ref().and_then(|e| {
match block.rules {