use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::higher;
use clippy_utils::method_chain_args;
use clippy_utils::source::snippet_with_applicability;
use clippy_utils::ty::is_type_diagnostic_item;
use if_chain::if_chain;
use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, MatchSource, PatKind, QPath};
+use rustc_hir::{Expr, ExprKind, PatKind, QPath};
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::sym;
impl<'tcx> LateLintPass<'tcx> for OkIfLet {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if_chain! { //begin checking variables
- if let ExprKind::Match(op, body, MatchSource::IfLetDesugar { .. }) = expr.kind; //test if expr is if let
- if let ExprKind::MethodCall(_, ok_span, result_types, _) = op.kind; //check is expr.ok() has type Result<T,E>.ok(, _)
- if let PatKind::TupleStruct(QPath::Resolved(_, x), y, _) = body[0].pat.kind; //get operation
- if method_chain_args(op, &["ok"]).is_some(); //test to see if using ok() methoduse std::marker::Sized;
+ if let Some(higher::IfLet { let_pat, let_expr, .. }) = higher::IfLet::hir(cx, expr);
+ if let ExprKind::MethodCall(_, ok_span, ref result_types, _) = let_expr.kind; //check is expr.ok() has type Result<T,E>.ok(, _)
+ if let PatKind::TupleStruct(QPath::Resolved(_, ref x), ref y, _) = let_pat.kind; //get operation
+ if method_chain_args(let_expr, &["ok"]).is_some(); //test to see if using ok() methoduse std::marker::Sized;
if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(&result_types[0]), sym::result_type);
if rustc_hir_pretty::to_string(rustc_hir_pretty::NO_ANN, |s| s.print_path(x, false)) == "Some";
then {
let mut applicability = Applicability::MachineApplicable;
let some_expr_string = snippet_with_applicability(cx, y[0].span, "", &mut applicability);
- let trimmed_ok = snippet_with_applicability(cx, op.span.until(ok_span), "", &mut applicability);
+ let trimmed_ok = snippet_with_applicability(cx, let_expr.span.until(ok_span), "", &mut applicability);
let sugg = format!(
"if let Ok({}) = {}",
some_expr_string,
span_lint_and_sugg(
cx,
IF_LET_SOME_RESULT,
- expr.span.with_hi(op.span.hi()),
+ expr.span.with_hi(let_expr.span.hi()),
"matching on `Some` with `ok()` is redundant",
&format!("consider matching on `Ok({})` and removing the call to `ok` instead", some_expr_string),
sugg,