diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/functions/impl_trait_in_params.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/functions/impl_trait_in_params.rs | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/functions/impl_trait_in_params.rs b/src/tools/clippy/clippy_lints/src/functions/impl_trait_in_params.rs new file mode 100644 index 000000000..2811a73f6 --- /dev/null +++ b/src/tools/clippy/clippy_lints/src/functions/impl_trait_in_params.rs @@ -0,0 +1,50 @@ +use clippy_utils::{diagnostics::span_lint_and_then, is_in_test_function}; + +use rustc_hir::{intravisit::FnKind, Body, HirId}; +use rustc_lint::LateContext; +use rustc_span::Span; + +use super::IMPL_TRAIT_IN_PARAMS; + +pub(super) fn check_fn<'tcx>(cx: &LateContext<'_>, kind: &'tcx FnKind<'_>, body: &'tcx Body<'_>, hir_id: HirId) { + if cx.tcx.visibility(cx.tcx.hir().body_owner_def_id(body.id())).is_public() && !is_in_test_function(cx.tcx, hir_id) + { + if let FnKind::ItemFn(ident, generics, _) = kind { + for param in generics.params { + if param.is_impl_trait() { + // No generics with nested generics, and no generics like FnMut(x) + span_lint_and_then( + cx, + IMPL_TRAIT_IN_PARAMS, + param.span, + "'`impl Trait` used as a function parameter'", + |diag| { + if let Some(gen_span) = generics.span_for_param_suggestion() { + diag.span_suggestion_with_style( + gen_span, + "add a type paremeter", + format!(", {{ /* Generic name */ }}: {}", ¶m.name.ident().as_str()[5..]), + rustc_errors::Applicability::HasPlaceholders, + rustc_errors::SuggestionStyle::ShowAlways, + ); + } else { + diag.span_suggestion_with_style( + Span::new( + body.params[0].span.lo() - rustc_span::BytePos(1), + ident.span.hi(), + ident.span.ctxt(), + ident.span.parent(), + ), + "add a type paremeter", + format!("<{{ /* Generic name */ }}: {}>", ¶m.name.ident().as_str()[5..]), + rustc_errors::Applicability::HasPlaceholders, + rustc_errors::SuggestionStyle::ShowAlways, + ); + } + }, + ); + } + } + } + } +} |