mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-30 10:45:18 +00:00
Split out match_as_ref
This commit is contained in:
Jason Newcomb
parent
75923dff5b
commit
bccf06f601
85
clippy_lints/src/matches/match_as_ref.rs
Normal file
85
clippy_lints/src/matches/match_as_ref.rs
Normal file
@ -0,0 +1,85 @@
|
||||
use clippy_utils::diagnostics::span_lint_and_sugg;
|
||||
use clippy_utils::source::snippet_with_applicability;
|
||||
use clippy_utils::{is_lang_ctor, peel_blocks};
|
||||
use rustc_errors::Applicability;
|
||||
use rustc_hir::{Arm, BindingAnnotation, Expr, ExprKind, LangItem, PatKind, QPath};
|
||||
use rustc_lint::LateContext;
|
||||
use rustc_middle::ty;
|
||||
|
||||
use super::MATCH_AS_REF;
|
||||
|
||||
pub(crate) fn check(cx: &LateContext<'_>, ex: &Expr<'_>, arms: &[Arm<'_>], expr: &Expr<'_>) {
|
||||
if arms.len() == 2 && arms[0].guard.is_none() && arms[1].guard.is_none() {
|
||||
let arm_ref: Option<BindingAnnotation> = if is_none_arm(cx, &arms[0]) {
|
||||
is_ref_some_arm(cx, &arms[1])
|
||||
} else if is_none_arm(cx, &arms[1]) {
|
||||
is_ref_some_arm(cx, &arms[0])
|
||||
} else {
|
||||
None
|
||||
};
|
||||
if let Some(rb) = arm_ref {
|
||||
let suggestion = if rb == BindingAnnotation::Ref {
|
||||
"as_ref"
|
||||
} else {
|
||||
"as_mut"
|
||||
};
|
||||
|
||||
let output_ty = cx.typeck_results().expr_ty(expr);
|
||||
let input_ty = cx.typeck_results().expr_ty(ex);
|
||||
|
||||
let cast = if_chain! {
|
||||
if let ty::Adt(_, substs) = input_ty.kind();
|
||||
let input_ty = substs.type_at(0);
|
||||
if let ty::Adt(_, substs) = output_ty.kind();
|
||||
let output_ty = substs.type_at(0);
|
||||
if let ty::Ref(_, output_ty, _) = *output_ty.kind();
|
||||
if input_ty != output_ty;
|
||||
then {
|
||||
".map(|x| x as _)"
|
||||
} else {
|
||||
""
|
||||
}
|
||||
};
|
||||
|
||||
let mut applicability = Applicability::MachineApplicable;
|
||||
span_lint_and_sugg(
|
||||
cx,
|
||||
MATCH_AS_REF,
|
||||
expr.span,
|
||||
&format!("use `{}()` instead", suggestion),
|
||||
"try this",
|
||||
format!(
|
||||
"{}.{}(){}",
|
||||
snippet_with_applicability(cx, ex.span, "_", &mut applicability),
|
||||
suggestion,
|
||||
cast,
|
||||
),
|
||||
applicability,
|
||||
);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Checks if arm has the form `None => None`
|
||||
fn is_none_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
|
||||
matches!(arm.pat.kind, PatKind::Path(ref qpath) if is_lang_ctor(cx, qpath, LangItem::OptionNone))
|
||||
}
|
||||
|
||||
// Checks if arm has the form `Some(ref v) => Some(v)` (checks for `ref` and `ref mut`)
|
||||
fn is_ref_some_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> Option<BindingAnnotation> {
|
||||
if_chain! {
|
||||
if let PatKind::TupleStruct(ref qpath, [first_pat, ..], _) = arm.pat.kind;
|
||||
if is_lang_ctor(cx, qpath, LangItem::OptionSome);
|
||||
if let PatKind::Binding(rb, .., ident, _) = first_pat.kind;
|
||||
if rb == BindingAnnotation::Ref || rb == BindingAnnotation::RefMut;
|
||||
if let ExprKind::Call(e, args) = peel_blocks(arm.body).kind;
|
||||
if let ExprKind::Path(ref some_path) = e.kind;
|
||||
if is_lang_ctor(cx, some_path, LangItem::OptionSome) && args.len() == 1;
|
||||
if let ExprKind::Path(QPath::Resolved(_, path2)) = args[0].kind;
|
||||
if path2.segments.len() == 1 && ident.name == path2.segments[0].ident.name;
|
||||
then {
|
||||
return Some(rb)
|
||||
}
|
||||
}
|
||||
None
|
||||
}
|
||||
@ -2,21 +2,18 @@ use clippy_utils::diagnostics::{multispan_sugg, span_lint_and_help, span_lint_an
|
||||
use clippy_utils::source::{indent_of, snippet, snippet_block, snippet_opt, snippet_with_applicability};
|
||||
use clippy_utils::sugg::Sugg;
|
||||
use clippy_utils::{
|
||||
get_parent_expr, is_lang_ctor, is_refutable, is_wild, meets_msrv, msrvs, path_to_local_id, peel_blocks,
|
||||
strip_pat_refs,
|
||||
get_parent_expr, is_refutable, is_wild, meets_msrv, msrvs, path_to_local_id, peel_blocks, strip_pat_refs,
|
||||
};
|
||||
use core::iter::once;
|
||||
use if_chain::if_chain;
|
||||
use rustc_errors::Applicability;
|
||||
use rustc_hir::LangItem::{OptionNone, OptionSome};
|
||||
use rustc_hir::{
|
||||
Arm, BindingAnnotation, BorrowKind, Expr, ExprKind, Local, MatchSource, Mutability, Node, Pat, PatKind, QPath,
|
||||
};
|
||||
use rustc_hir::{Arm, BorrowKind, Expr, ExprKind, Local, MatchSource, Mutability, Node, Pat, PatKind, QPath};
|
||||
use rustc_lint::{LateContext, LateLintPass};
|
||||
use rustc_middle::ty;
|
||||
use rustc_semver::RustcVersion;
|
||||
use rustc_session::{declare_tool_lint, impl_lint_pass};
|
||||
|
||||
mod match_as_ref;
|
||||
mod match_bool;
|
||||
mod match_like_matches;
|
||||
mod match_same_arms;
|
||||
@ -627,7 +624,7 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
|
||||
overlapping_arms::check(cx, ex, arms);
|
||||
match_wild_err_arm::check(cx, ex, arms);
|
||||
match_wild_enum::check(cx, ex, arms);
|
||||
check_match_as_ref(cx, ex, arms, expr);
|
||||
match_as_ref::check(cx, ex, arms, expr);
|
||||
check_wild_in_or_pats(cx, arms);
|
||||
|
||||
if self.infallible_destructuring_match_linted {
|
||||
@ -738,58 +735,6 @@ where
|
||||
});
|
||||
}
|
||||
|
||||
fn check_match_as_ref(cx: &LateContext<'_>, ex: &Expr<'_>, arms: &[Arm<'_>], expr: &Expr<'_>) {
|
||||
if arms.len() == 2 && arms[0].guard.is_none() && arms[1].guard.is_none() {
|
||||
let arm_ref: Option<BindingAnnotation> = if is_none_arm(cx, &arms[0]) {
|
||||
is_ref_some_arm(cx, &arms[1])
|
||||
} else if is_none_arm(cx, &arms[1]) {
|
||||
is_ref_some_arm(cx, &arms[0])
|
||||
} else {
|
||||
None
|
||||
};
|
||||
if let Some(rb) = arm_ref {
|
||||
let suggestion = if rb == BindingAnnotation::Ref {
|
||||
"as_ref"
|
||||
} else {
|
||||
"as_mut"
|
||||
};
|
||||
|
||||
let output_ty = cx.typeck_results().expr_ty(expr);
|
||||
let input_ty = cx.typeck_results().expr_ty(ex);
|
||||
|
||||
let cast = if_chain! {
|
||||
if let ty::Adt(_, substs) = input_ty.kind();
|
||||
let input_ty = substs.type_at(0);
|
||||
if let ty::Adt(_, substs) = output_ty.kind();
|
||||
let output_ty = substs.type_at(0);
|
||||
if let ty::Ref(_, output_ty, _) = *output_ty.kind();
|
||||
if input_ty != output_ty;
|
||||
then {
|
||||
".map(|x| x as _)"
|
||||
} else {
|
||||
""
|
||||
}
|
||||
};
|
||||
|
||||
let mut applicability = Applicability::MachineApplicable;
|
||||
span_lint_and_sugg(
|
||||
cx,
|
||||
MATCH_AS_REF,
|
||||
expr.span,
|
||||
&format!("use `{}()` instead", suggestion),
|
||||
"try this",
|
||||
format!(
|
||||
"{}.{}(){}",
|
||||
snippet_with_applicability(cx, ex.span, "_", &mut applicability),
|
||||
suggestion,
|
||||
cast,
|
||||
),
|
||||
applicability,
|
||||
);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn check_wild_in_or_pats(cx: &LateContext<'_>, arms: &[Arm<'_>]) {
|
||||
for arm in arms {
|
||||
if let PatKind::Or(fields) = arm.pat.kind {
|
||||
@ -965,30 +910,6 @@ fn opt_parent_let<'a>(cx: &LateContext<'a>, ex: &Expr<'a>) -> Option<&'a Local<'
|
||||
None
|
||||
}
|
||||
|
||||
// Checks if arm has the form `None => None`
|
||||
fn is_none_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
|
||||
matches!(arm.pat.kind, PatKind::Path(ref qpath) if is_lang_ctor(cx, qpath, OptionNone))
|
||||
}
|
||||
|
||||
// Checks if arm has the form `Some(ref v) => Some(v)` (checks for `ref` and `ref mut`)
|
||||
fn is_ref_some_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> Option<BindingAnnotation> {
|
||||
if_chain! {
|
||||
if let PatKind::TupleStruct(ref qpath, [first_pat, ..], _) = arm.pat.kind;
|
||||
if is_lang_ctor(cx, qpath, OptionSome);
|
||||
if let PatKind::Binding(rb, .., ident, _) = first_pat.kind;
|
||||
if rb == BindingAnnotation::Ref || rb == BindingAnnotation::RefMut;
|
||||
if let ExprKind::Call(e, args) = peel_blocks(arm.body).kind;
|
||||
if let ExprKind::Path(ref some_path) = e.kind;
|
||||
if is_lang_ctor(cx, some_path, OptionSome) && args.len() == 1;
|
||||
if let ExprKind::Path(QPath::Resolved(_, path2)) = args[0].kind;
|
||||
if path2.segments.len() == 1 && ident.name == path2.segments[0].ident.name;
|
||||
then {
|
||||
return Some(rb)
|
||||
}
|
||||
}
|
||||
None
|
||||
}
|
||||
|
||||
fn has_multiple_ref_pats<'a, 'b, I>(pats: I) -> bool
|
||||
where
|
||||
'b: 'a,
|
||||
|
||||
Loading…
Reference in New Issue
Block a user