Skip to content

Refactor: Cleanup one part of assign_ops lint #3852

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Mar 9, 2019
Merged

Refactor: Cleanup one part of assign_ops lint #3852

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
5c9221f
Refactor: Cleanup one part of assign_ops lint
phansch Mar 7, 2019
9494f22
cargo fmt
phansch Mar 8, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
98 changes: 52 additions & 46 deletions clippy_lints/src/assign_ops.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -68,52 +68,16 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for AssignOps {
match &expr.node {
hir::ExprKind::AssignOp(op, lhs, rhs) => {
if let hir::ExprKind::Binary(binop, l, r) = &rhs.node {
if op.node == binop.node {
let lint = |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| {
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(
expr.span,
&format!(
"Did you mean {} = {} {} {} or {}? Consider replacing it with",
snip_a,
snip_a,
op.node.as_str(),
snip_r,
long
),
format!("{} {}= {}", snip_a, op.node.as_str(), snip_r),
Applicability::MachineApplicable,
);
db.span_suggestion(
expr.span,
"or",
long,
Applicability::MachineApplicable, // snippet
);
}
},
);
};
// lhs op= l op r
if SpanlessEq::new(cx).ignore_fn().eq_expr(lhs, l) {
lint(lhs, r);
}
// lhs op= l commutative_op r
if is_commutative(op.node) && SpanlessEq::new(cx).ignore_fn().eq_expr(lhs, r) {
lint(lhs, l);
}
if op.node != binop.node {
return;
}
// lhs op= l op r
if SpanlessEq::new(cx).ignore_fn().eq_expr(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) {
lint_misrefactored_assign_op(cx, expr, *op, rhs, lhs, l);
}
}
},
Expand Down Expand Up @@ -234,6 +198,48 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for AssignOps {
}
}

fn lint_misrefactored_assign_op(
cx: &LateContext<'_, '_>,
expr: &hir::Expr,
op: hir::BinOp,
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| {
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(
expr.span,
&format!(
"Did you mean {} = {} {} {} or {}? Consider replacing it with",
snip_a,
snip_a,
op.node.as_str(),
snip_r,
long
),
format!("{} {}= {}", snip_a, op.node.as_str(), snip_r),
Applicability::MachineApplicable,
);
db.span_suggestion(
expr.span,
"or",
long,
Applicability::MachineApplicable, // snippet
);
}
},
);
}

fn is_commutative(op: hir::BinOpKind) -> bool {
use rustc::hir::BinOpKind::*;
match op {
Expand Down