Move qpath_spans into FunctionKind

Author: roife

clippy_lints/src/methods/unnecessary_fallible_conversions.rs

@@ -12,15 +12,15 @@ use super::UNNECESSARY_FALLIBLE_CONVERSIONS;
 
 /// What function is being called and whether that call is written as a method call or a function
 /// call
-#[derive(Copy, Clone)]
+#[derive(Clone)]
 #[expect(clippy::enum_variant_names)]
 enum FunctionKind {
  /// `T::try_from(U)`
- TryFromFunction,
+ TryFromFunction(Option<Vec<Span>>),
  /// `t.try_into()`
  TryIntoMethod,
  /// `U::try_into(t)`
- TryIntoFunction,
+ TryIntoFunction(Option<Vec<Span>>),
 }
 
 fn check<'tcx>(
@@ -29,15 +29,14 @@ fn check<'tcx>(
  node_args: ty::GenericArgsRef<'tcx>,
  kind: FunctionKind,
  primary_span: Span,
- qpath: Option<&QPath<'_>>,
 ) {
  if let &[self_ty, other_ty] = node_args.as_slice()
  // useless_conversion already warns `T::try_from(T)`, so ignore it here
  && self_ty != other_ty
  && let Some(self_ty) = self_ty.as_type()
  && let Some(from_into_trait) = cx.tcx.get_diagnostic_item(match kind {
- FunctionKind::TryFromFunction => sym::From,
- FunctionKind::TryIntoMethod | FunctionKind::TryIntoFunction => sym::Into,
+ FunctionKind::TryFromFunction(_) => sym::From,
+ FunctionKind::TryIntoMethod | FunctionKind::TryIntoFunction(_) => sym::Into,
  })
  // If `T: TryFrom<U>` and `T: From<U>` both exist, then that means that the `TryFrom`
  // _must_ be from the blanket impl and cannot have been manually implemented
@@ -70,21 +69,12 @@ fn check<'tcx>(
  primary_span
  };
 
- let qpath_spans = qpath.and_then(|qpath| match qpath {
- QPath::Resolved(_, path) => {
- let segments = path.segments.iter().map(|seg| seg.ident).collect::<Vec<_>>();
- (segments.len() == 2).then(|| vec![segments[0].span, segments[1].span])
- },
- QPath::TypeRelative(_, seg) => Some(vec![seg.ident.span]),
- QPath::LangItem(_, _) => unreachable!("`TryFrom` and `TryInto` are not lang items"),
- });
-
- let (source_ty, target_ty, sugg, applicability) = match (kind, &qpath_spans, parent_unwrap_call) {
- (FunctionKind::TryIntoMethod, _, Some(unwrap_span)) => {
+ let (source_ty, target_ty, sugg, applicability) = match (kind, parent_unwrap_call) {
+ (FunctionKind::TryIntoMethod, Some(unwrap_span)) => {
  let sugg = vec![(primary_span, String::from("into")), (unwrap_span, String::new())];
  (self_ty, other_ty, sugg, Applicability::MachineApplicable)
  },
- (FunctionKind::TryFromFunction, Some(spans), Some(unwrap_span)) => {
+ (FunctionKind::TryFromFunction(Some(spans)), Some(unwrap_span)) => {
  let sugg = match spans.len() {
  1 => vec![(spans[0], String::from("from")), (unwrap_span, String::new())],
  2 => vec![
@@ -96,7 +86,7 @@ fn check<'tcx>(
  };
  (other_ty, self_ty, sugg, Applicability::MachineApplicable)
  },
- (FunctionKind::TryIntoFunction, Some(spans), Some(unwrap_span)) => {
+ (FunctionKind::TryIntoFunction(Some(spans)), Some(unwrap_span)) => {
  let sugg = match spans.len() {
  1 => vec![(spans[0], String::from("into")), (unwrap_span, String::new())],
  2 => vec![
@@ -108,15 +98,15 @@ fn check<'tcx>(
  };
  (self_ty, other_ty, sugg, Applicability::MachineApplicable)
  },
- (FunctionKind::TryFromFunction, _, _) => {
+ (FunctionKind::TryFromFunction(_), _) => {
  let sugg = vec![(primary_span, String::from("From::from"))];
  (other_ty, self_ty, sugg, Applicability::Unspecified)
  },
- (FunctionKind::TryIntoFunction, _, _) => {
+ (FunctionKind::TryIntoFunction(_), _) => {
  let sugg = vec![(primary_span, String::from("Into::into"))];
  (self_ty, other_ty, sugg, Applicability::Unspecified)
  },
- (FunctionKind::TryIntoMethod, _, _) => {
+ (FunctionKind::TryIntoMethod, _) => {
  let sugg = vec![(primary_span, String::from("into"))];
  (self_ty, other_ty, sugg, Applicability::Unspecified)
  },
@@ -147,7 +137,6 @@ pub(super) fn check_method(cx: &LateContext<'_>, expr: &Expr<'_>) {
  cx.typeck_results().node_args(expr.hir_id),
  FunctionKind::TryIntoMethod,
  path.ident.span,
- None,
  );
  }
 }
@@ -160,17 +149,25 @@ pub(super) fn check_function(cx: &LateContext<'_>, expr: &Expr<'_>, callee: &Exp
  && let Some(item_def_id) = cx.qpath_res(qpath, callee.hir_id).opt_def_id()
  && let Some(trait_def_id) = cx.tcx.trait_of_item(item_def_id)
  {
+ let qpath_spans = match qpath {
+ QPath::Resolved(_, path) => {
+ let segments = path.segments.iter().map(|seg| seg.ident).collect::<Vec<_>>();
+ (segments.len() == 2).then(|| vec![segments[0].span, segments[1].span])
+ },
+ QPath::TypeRelative(_, seg) => Some(vec![seg.ident.span]),
+ QPath::LangItem(_, _) => unreachable!("`TryFrom` and `TryInto` are not lang items"),
+ };
+
  check(
  cx,
  expr,
  cx.typeck_results().node_args(callee.hir_id),
  match cx.tcx.get_diagnostic_name(trait_def_id) {
- Some(sym::TryFrom) => FunctionKind::TryFromFunction,
- Some(sym::TryInto) => FunctionKind::TryIntoFunction,
+ Some(sym::TryFrom) => FunctionKind::TryFromFunction(qpath_spans),
+ Some(sym::TryInto) => FunctionKind::TryIntoFunction(qpath_spans),
  _ => return,
  },
  callee.span,
- Some(qpath),
  );
  }
 }