Merge ManualUnwrapOr
into Matches
lint pass
This commit is contained in:
parent
81e44502ac
commit
b337f9e62e
@ -136,7 +136,6 @@
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LintId::of(manual_map::MANUAL_MAP),
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LintId::of(manual_map::MANUAL_MAP),
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LintId::of(manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE),
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LintId::of(manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE),
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LintId::of(manual_strip::MANUAL_STRIP),
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LintId::of(manual_strip::MANUAL_STRIP),
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LintId::of(manual_unwrap_or::MANUAL_UNWRAP_OR),
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LintId::of(map_clone::MAP_CLONE),
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LintId::of(map_clone::MAP_CLONE),
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LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
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LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
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LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
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LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
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@ -144,6 +143,7 @@
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LintId::of(match_str_case_mismatch::MATCH_STR_CASE_MISMATCH),
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LintId::of(match_str_case_mismatch::MATCH_STR_CASE_MISMATCH),
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LintId::of(matches::COLLAPSIBLE_MATCH),
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LintId::of(matches::COLLAPSIBLE_MATCH),
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LintId::of(matches::INFALLIBLE_DESTRUCTURING_MATCH),
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LintId::of(matches::INFALLIBLE_DESTRUCTURING_MATCH),
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LintId::of(matches::MANUAL_UNWRAP_OR),
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LintId::of(matches::MATCH_AS_REF),
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LintId::of(matches::MATCH_AS_REF),
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LintId::of(matches::MATCH_LIKE_MATCHES_MACRO),
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LintId::of(matches::MATCH_LIKE_MATCHES_MACRO),
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LintId::of(matches::MATCH_OVERLAPPING_ARM),
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LintId::of(matches::MATCH_OVERLAPPING_ARM),
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@ -25,9 +25,9 @@
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LintId::of(loops::SINGLE_ELEMENT_LOOP),
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LintId::of(loops::SINGLE_ELEMENT_LOOP),
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LintId::of(loops::WHILE_LET_LOOP),
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LintId::of(loops::WHILE_LET_LOOP),
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LintId::of(manual_strip::MANUAL_STRIP),
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LintId::of(manual_strip::MANUAL_STRIP),
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LintId::of(manual_unwrap_or::MANUAL_UNWRAP_OR),
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LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
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LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
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LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
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LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
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LintId::of(matches::MANUAL_UNWRAP_OR),
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LintId::of(matches::MATCH_AS_REF),
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LintId::of(matches::MATCH_AS_REF),
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LintId::of(matches::MATCH_SINGLE_BINDING),
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LintId::of(matches::MATCH_SINGLE_BINDING),
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LintId::of(matches::NEEDLESS_MATCH),
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LintId::of(matches::NEEDLESS_MATCH),
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@ -254,7 +254,6 @@
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manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE,
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manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE,
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manual_ok_or::MANUAL_OK_OR,
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manual_ok_or::MANUAL_OK_OR,
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manual_strip::MANUAL_STRIP,
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manual_strip::MANUAL_STRIP,
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manual_unwrap_or::MANUAL_UNWRAP_OR,
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map_clone::MAP_CLONE,
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map_clone::MAP_CLONE,
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map_err_ignore::MAP_ERR_IGNORE,
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map_err_ignore::MAP_ERR_IGNORE,
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map_unit_fn::OPTION_MAP_UNIT_FN,
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map_unit_fn::OPTION_MAP_UNIT_FN,
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@ -264,6 +263,7 @@
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match_str_case_mismatch::MATCH_STR_CASE_MISMATCH,
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match_str_case_mismatch::MATCH_STR_CASE_MISMATCH,
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matches::COLLAPSIBLE_MATCH,
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matches::COLLAPSIBLE_MATCH,
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matches::INFALLIBLE_DESTRUCTURING_MATCH,
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matches::INFALLIBLE_DESTRUCTURING_MATCH,
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matches::MANUAL_UNWRAP_OR,
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matches::MATCH_AS_REF,
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matches::MATCH_AS_REF,
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matches::MATCH_BOOL,
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matches::MATCH_BOOL,
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matches::MATCH_LIKE_MATCHES_MACRO,
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matches::MATCH_LIKE_MATCHES_MACRO,
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@ -283,7 +283,6 @@ macro_rules! declare_clippy_lint {
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mod manual_non_exhaustive;
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mod manual_non_exhaustive;
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mod manual_ok_or;
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mod manual_ok_or;
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mod manual_strip;
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mod manual_strip;
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mod manual_unwrap_or;
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mod map_clone;
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mod map_clone;
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mod map_err_ignore;
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mod map_err_ignore;
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mod map_unit_fn;
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mod map_unit_fn;
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@ -834,7 +833,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
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store.register_late_pass(|| Box::new(repeat_once::RepeatOnce));
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store.register_late_pass(|| Box::new(repeat_once::RepeatOnce));
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store.register_late_pass(|| Box::new(unwrap_in_result::UnwrapInResult));
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store.register_late_pass(|| Box::new(unwrap_in_result::UnwrapInResult));
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store.register_late_pass(|| Box::new(self_assignment::SelfAssignment));
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store.register_late_pass(|| Box::new(self_assignment::SelfAssignment));
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store.register_late_pass(|| Box::new(manual_unwrap_or::ManualUnwrapOr));
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store.register_late_pass(|| Box::new(manual_ok_or::ManualOkOr));
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store.register_late_pass(|| Box::new(manual_ok_or::ManualOkOr));
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store.register_late_pass(|| Box::new(float_equality_without_abs::FloatEqualityWithoutAbs));
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store.register_late_pass(|| Box::new(float_equality_without_abs::FloatEqualityWithoutAbs));
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store.register_late_pass(|| Box::new(semicolon_if_nothing_returned::SemicolonIfNothingReturned));
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store.register_late_pass(|| Box::new(semicolon_if_nothing_returned::SemicolonIfNothingReturned));
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@ -1,123 +0,0 @@
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use clippy_utils::consts::constant_simple;
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use clippy_utils::diagnostics::span_lint_and_sugg;
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use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
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use clippy_utils::ty::is_type_diagnostic_item;
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use clippy_utils::usage::contains_return_break_continue_macro;
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use clippy_utils::{in_constant, is_lang_ctor, path_to_local_id, sugg};
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use if_chain::if_chain;
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use rustc_errors::Applicability;
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use rustc_hir::LangItem::{OptionNone, OptionSome, ResultErr, ResultOk};
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use rustc_hir::{Arm, Expr, ExprKind, PatKind};
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use rustc_lint::LintContext;
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::lint::in_external_macro;
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use rustc_session::{declare_lint_pass, declare_tool_lint};
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use rustc_span::sym;
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declare_clippy_lint! {
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/// ### What it does
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/// Finds patterns that reimplement `Option::unwrap_or` or `Result::unwrap_or`.
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///
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/// ### Why is this bad?
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/// Concise code helps focusing on behavior instead of boilerplate.
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///
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/// ### Example
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/// ```rust
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/// let foo: Option<i32> = None;
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/// match foo {
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/// Some(v) => v,
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/// None => 1,
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/// };
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/// ```
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///
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/// Use instead:
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/// ```rust
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/// let foo: Option<i32> = None;
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/// foo.unwrap_or(1);
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/// ```
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#[clippy::version = "1.49.0"]
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pub MANUAL_UNWRAP_OR,
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complexity,
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"finds patterns that can be encoded more concisely with `Option::unwrap_or` or `Result::unwrap_or`"
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}
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declare_lint_pass!(ManualUnwrapOr => [MANUAL_UNWRAP_OR]);
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impl<'tcx> LateLintPass<'tcx> for ManualUnwrapOr {
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fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
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if in_external_macro(cx.sess(), expr.span) || in_constant(cx, expr.hir_id) {
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return;
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}
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lint_manual_unwrap_or(cx, expr);
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}
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}
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fn lint_manual_unwrap_or<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
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fn applicable_or_arm<'a>(cx: &LateContext<'_>, arms: &'a [Arm<'a>]) -> Option<&'a Arm<'a>> {
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if_chain! {
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if arms.len() == 2;
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if arms.iter().all(|arm| arm.guard.is_none());
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if let Some((idx, or_arm)) = arms.iter().enumerate().find(|(_, arm)| {
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match arm.pat.kind {
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PatKind::Path(ref qpath) => is_lang_ctor(cx, qpath, OptionNone),
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PatKind::TupleStruct(ref qpath, [pat], _) =>
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matches!(pat.kind, PatKind::Wild) && is_lang_ctor(cx, qpath, ResultErr),
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_ => false,
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}
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});
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let unwrap_arm = &arms[1 - idx];
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if let PatKind::TupleStruct(ref qpath, [unwrap_pat], _) = unwrap_arm.pat.kind;
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if is_lang_ctor(cx, qpath, OptionSome) || is_lang_ctor(cx, qpath, ResultOk);
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if let PatKind::Binding(_, binding_hir_id, ..) = unwrap_pat.kind;
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if path_to_local_id(unwrap_arm.body, binding_hir_id);
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if cx.typeck_results().expr_adjustments(unwrap_arm.body).is_empty();
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if !contains_return_break_continue_macro(or_arm.body);
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then {
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Some(or_arm)
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} else {
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None
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}
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}
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}
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if_chain! {
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if let ExprKind::Match(scrutinee, match_arms, _) = expr.kind;
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let ty = cx.typeck_results().expr_ty(scrutinee);
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if let Some(ty_name) = if is_type_diagnostic_item(cx, ty, sym::Option) {
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Some("Option")
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} else if is_type_diagnostic_item(cx, ty, sym::Result) {
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Some("Result")
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} else {
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None
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};
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if let Some(or_arm) = applicable_or_arm(cx, match_arms);
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if let Some(or_body_snippet) = snippet_opt(cx, or_arm.body.span);
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if let Some(indent) = indent_of(cx, expr.span);
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if constant_simple(cx, cx.typeck_results(), or_arm.body).is_some();
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then {
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let reindented_or_body =
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reindent_multiline(or_body_snippet.into(), true, Some(indent));
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let suggestion = if scrutinee.span.from_expansion() {
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// we don't want parentheses around macro, e.g. `(some_macro!()).unwrap_or(0)`
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sugg::Sugg::hir_with_macro_callsite(cx, scrutinee, "..")
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}
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else {
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sugg::Sugg::hir(cx, scrutinee, "..").maybe_par()
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};
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span_lint_and_sugg(
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cx,
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MANUAL_UNWRAP_OR, expr.span,
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&format!("this pattern reimplements `{}::unwrap_or`", ty_name),
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"replace with",
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format!(
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"{}.unwrap_or({})",
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suggestion,
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reindented_or_body,
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),
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Applicability::MachineApplicable,
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);
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}
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}
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}
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83
clippy_lints/src/matches/manual_unwrap_or.rs
Normal file
83
clippy_lints/src/matches/manual_unwrap_or.rs
Normal file
@ -0,0 +1,83 @@
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use clippy_utils::consts::constant_simple;
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use clippy_utils::diagnostics::span_lint_and_sugg;
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use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
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use clippy_utils::ty::is_type_diagnostic_item;
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use clippy_utils::usage::contains_return_break_continue_macro;
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use clippy_utils::{is_lang_ctor, path_to_local_id, sugg};
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use if_chain::if_chain;
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use rustc_errors::Applicability;
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use rustc_hir::LangItem::{OptionNone, OptionSome, ResultErr, ResultOk};
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use rustc_hir::{Arm, Expr, PatKind};
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use rustc_lint::LateContext;
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use rustc_span::sym;
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use super::MANUAL_UNWRAP_OR;
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pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'tcx>, scrutinee: &'tcx Expr<'_>, arms: &'tcx [Arm<'_>]) {
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let ty = cx.typeck_results().expr_ty(scrutinee);
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if_chain! {
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if let Some(ty_name) = if is_type_diagnostic_item(cx, ty, sym::Option) {
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Some("Option")
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} else if is_type_diagnostic_item(cx, ty, sym::Result) {
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Some("Result")
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} else {
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None
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};
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if let Some(or_arm) = applicable_or_arm(cx, arms);
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if let Some(or_body_snippet) = snippet_opt(cx, or_arm.body.span);
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if let Some(indent) = indent_of(cx, expr.span);
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if constant_simple(cx, cx.typeck_results(), or_arm.body).is_some();
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then {
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let reindented_or_body =
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reindent_multiline(or_body_snippet.into(), true, Some(indent));
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let suggestion = if scrutinee.span.from_expansion() {
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// we don't want parentheses around macro, e.g. `(some_macro!()).unwrap_or(0)`
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sugg::Sugg::hir_with_macro_callsite(cx, scrutinee, "..")
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}
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else {
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sugg::Sugg::hir(cx, scrutinee, "..").maybe_par()
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};
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span_lint_and_sugg(
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cx,
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MANUAL_UNWRAP_OR, expr.span,
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&format!("this pattern reimplements `{}::unwrap_or`", ty_name),
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"replace with",
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format!(
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"{}.unwrap_or({})",
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suggestion,
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reindented_or_body,
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),
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Applicability::MachineApplicable,
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);
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}
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}
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}
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fn applicable_or_arm<'a>(cx: &LateContext<'_>, arms: &'a [Arm<'a>]) -> Option<&'a Arm<'a>> {
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if_chain! {
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if arms.len() == 2;
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if arms.iter().all(|arm| arm.guard.is_none());
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if let Some((idx, or_arm)) = arms.iter().enumerate().find(|(_, arm)| {
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match arm.pat.kind {
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PatKind::Path(ref qpath) => is_lang_ctor(cx, qpath, OptionNone),
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PatKind::TupleStruct(ref qpath, [pat], _) =>
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matches!(pat.kind, PatKind::Wild) && is_lang_ctor(cx, qpath, ResultErr),
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_ => false,
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}
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});
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let unwrap_arm = &arms[1 - idx];
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if let PatKind::TupleStruct(ref qpath, [unwrap_pat], _) = unwrap_arm.pat.kind;
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if is_lang_ctor(cx, qpath, OptionSome) || is_lang_ctor(cx, qpath, ResultOk);
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if let PatKind::Binding(_, binding_hir_id, ..) = unwrap_pat.kind;
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if path_to_local_id(unwrap_arm.body, binding_hir_id);
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if cx.typeck_results().expr_adjustments(unwrap_arm.body).is_empty();
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if !contains_return_break_continue_macro(or_arm.body);
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then {
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Some(or_arm)
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} else {
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None
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}
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}
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}
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@ -1,5 +1,5 @@
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use clippy_utils::source::{snippet_opt, span_starts_with, walk_span_to_context};
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use clippy_utils::source::{snippet_opt, span_starts_with, walk_span_to_context};
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use clippy_utils::{higher, meets_msrv, msrvs};
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use clippy_utils::{higher, in_constant, meets_msrv, msrvs};
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use rustc_hir::{Arm, Expr, ExprKind, Local, MatchSource, Pat};
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use rustc_hir::{Arm, Expr, ExprKind, Local, MatchSource, Pat};
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use rustc_lexer::{tokenize, TokenKind};
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use rustc_lexer::{tokenize, TokenKind};
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use rustc_lint::{LateContext, LateLintPass, LintContext};
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use rustc_lint::{LateContext, LateLintPass, LintContext};
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@ -10,6 +10,7 @@
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mod collapsible_match;
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mod collapsible_match;
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mod infallible_destructuring_match;
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mod infallible_destructuring_match;
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mod manual_unwrap_or;
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mod match_as_ref;
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mod match_as_ref;
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mod match_bool;
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mod match_bool;
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mod match_like_matches;
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mod match_like_matches;
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@ -650,6 +651,33 @@
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"Nested `match` or `if let` expressions where the patterns may be \"collapsed\" together."
|
"Nested `match` or `if let` expressions where the patterns may be \"collapsed\" together."
|
||||||
}
|
}
|
||||||
|
|
||||||
|
declare_clippy_lint! {
|
||||||
|
/// ### What it does
|
||||||
|
/// Finds patterns that reimplement `Option::unwrap_or` or `Result::unwrap_or`.
|
||||||
|
///
|
||||||
|
/// ### Why is this bad?
|
||||||
|
/// Concise code helps focusing on behavior instead of boilerplate.
|
||||||
|
///
|
||||||
|
/// ### Example
|
||||||
|
/// ```rust
|
||||||
|
/// let foo: Option<i32> = None;
|
||||||
|
/// match foo {
|
||||||
|
/// Some(v) => v,
|
||||||
|
/// None => 1,
|
||||||
|
/// };
|
||||||
|
/// ```
|
||||||
|
///
|
||||||
|
/// Use instead:
|
||||||
|
/// ```rust
|
||||||
|
/// let foo: Option<i32> = None;
|
||||||
|
/// foo.unwrap_or(1);
|
||||||
|
/// ```
|
||||||
|
#[clippy::version = "1.49.0"]
|
||||||
|
pub MANUAL_UNWRAP_OR,
|
||||||
|
complexity,
|
||||||
|
"finds patterns that can be encoded more concisely with `Option::unwrap_or` or `Result::unwrap_or`"
|
||||||
|
}
|
||||||
|
|
||||||
#[derive(Default)]
|
#[derive(Default)]
|
||||||
pub struct Matches {
|
pub struct Matches {
|
||||||
msrv: Option<RustcVersion>,
|
msrv: Option<RustcVersion>,
|
||||||
@ -685,6 +713,7 @@ pub fn new(msrv: Option<RustcVersion>) -> Self {
|
|||||||
MATCH_SAME_ARMS,
|
MATCH_SAME_ARMS,
|
||||||
NEEDLESS_MATCH,
|
NEEDLESS_MATCH,
|
||||||
COLLAPSIBLE_MATCH,
|
COLLAPSIBLE_MATCH,
|
||||||
|
MANUAL_UNWRAP_OR,
|
||||||
]);
|
]);
|
||||||
|
|
||||||
impl<'tcx> LateLintPass<'tcx> for Matches {
|
impl<'tcx> LateLintPass<'tcx> for Matches {
|
||||||
@ -722,6 +751,10 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
|
|||||||
match_as_ref::check(cx, ex, arms, expr);
|
match_as_ref::check(cx, ex, arms, expr);
|
||||||
needless_match::check_match(cx, ex, arms, expr);
|
needless_match::check_match(cx, ex, arms, expr);
|
||||||
|
|
||||||
|
if !in_constant(cx, expr.hir_id) {
|
||||||
|
manual_unwrap_or::check(cx, expr, ex, arms);
|
||||||
|
}
|
||||||
|
|
||||||
if self.infallible_destructuring_match_linted {
|
if self.infallible_destructuring_match_linted {
|
||||||
self.infallible_destructuring_match_linted = false;
|
self.infallible_destructuring_match_linted = false;
|
||||||
} else {
|
} else {
|
||||||
|
Loading…
Reference in New Issue
Block a user