| use crate::utils::span_lint; |
| use rustc::hir; |
| use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass}; |
| use rustc::{declare_lint_pass, declare_tool_lint}; |
| use syntax::ast; |
| use syntax::source_map::Span; |
| |
| declare_clippy_lint! { |
| /// **What it does:** it lints if an exported function, method, trait method with default impl, |
| /// or trait method impl is not `#[inline]`. |
| /// |
| /// **Why is this bad?** In general, it is not. Functions can be inlined across |
| /// crates when that's profitable as long as any form of LTO is used. When LTO is disabled, |
| /// functions that are not `#[inline]` cannot be inlined across crates. Certain types of crates |
| /// might intend for most of the methods in their public API to be able to be inlined across |
| /// crates even when LTO is disabled. For these types of crates, enabling this lint might make |
| /// sense. It allows the crate to require all exported methods to be `#[inline]` by default, and |
| /// then opt out for specific methods where this might not make sense. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// ```rust |
| /// pub fn foo() {} // missing #[inline] |
| /// fn ok() {} // ok |
| /// #[inline] pub fn bar() {} // ok |
| /// #[inline(always)] pub fn baz() {} // ok |
| /// |
| /// pub trait Bar { |
| /// fn bar(); // ok |
| /// fn def_bar() {} // missing #[inline] |
| /// } |
| /// |
| /// struct Baz; |
| /// impl Baz { |
| /// fn priv() {} // ok |
| /// } |
| /// |
| /// impl Bar for Baz { |
| /// fn bar() {} // ok - Baz is not exported |
| /// } |
| /// |
| /// pub struct PubBaz; |
| /// impl PubBaz { |
| /// fn priv() {} // ok |
| /// pub not_ptriv() {} // missing #[inline] |
| /// } |
| /// |
| /// impl Bar for PubBaz { |
| /// fn bar() {} // missing #[inline] |
| /// fn def_bar() {} // missing #[inline] |
| /// } |
| /// ``` |
| pub MISSING_INLINE_IN_PUBLIC_ITEMS, |
| restriction, |
| "detects missing #[inline] attribute for public callables (functions, trait methods, methods...)" |
| } |
| |
| fn check_missing_inline_attrs(cx: &LateContext<'_, '_>, attrs: &[ast::Attribute], sp: Span, desc: &'static str) { |
| let has_inline = attrs.iter().any(|a| a.check_name(sym!(inline))); |
| if !has_inline { |
| span_lint( |
| cx, |
| MISSING_INLINE_IN_PUBLIC_ITEMS, |
| sp, |
| &format!("missing `#[inline]` for {}", desc), |
| ); |
| } |
| } |
| |
| fn is_executable(cx: &LateContext<'_, '_>) -> bool { |
| use rustc::session::config::CrateType; |
| |
| cx.tcx.sess.crate_types.get().iter().any(|t: &CrateType| match t { |
| CrateType::Executable => true, |
| _ => false, |
| }) |
| } |
| |
| declare_lint_pass!(MissingInline => [MISSING_INLINE_IN_PUBLIC_ITEMS]); |
| |
| impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingInline { |
| fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, it: &'tcx hir::Item) { |
| if is_executable(cx) { |
| return; |
| } |
| |
| if !cx.access_levels.is_exported(it.hir_id) { |
| return; |
| } |
| match it.node { |
| hir::ItemKind::Fn(..) => { |
| let desc = "a function"; |
| check_missing_inline_attrs(cx, &it.attrs, it.span, desc); |
| }, |
| hir::ItemKind::Trait(ref _is_auto, ref _unsafe, ref _generics, ref _bounds, ref trait_items) => { |
| // note: we need to check if the trait is exported so we can't use |
| // `LateLintPass::check_trait_item` here. |
| for tit in trait_items { |
| let tit_ = cx.tcx.hir().trait_item(tit.id); |
| match tit_.node { |
| hir::TraitItemKind::Const(..) | hir::TraitItemKind::Type(..) => {}, |
| hir::TraitItemKind::Method(..) => { |
| if tit.defaultness.has_value() { |
| // trait method with default body needs inline in case |
| // an impl is not provided |
| let desc = "a default trait method"; |
| let item = cx.tcx.hir().expect_trait_item(tit.id.hir_id); |
| check_missing_inline_attrs(cx, &item.attrs, item.span, desc); |
| } |
| }, |
| } |
| } |
| }, |
| hir::ItemKind::Const(..) |
| | hir::ItemKind::Enum(..) |
| | hir::ItemKind::Mod(..) |
| | hir::ItemKind::Static(..) |
| | hir::ItemKind::Struct(..) |
| | hir::ItemKind::TraitAlias(..) |
| | hir::ItemKind::GlobalAsm(..) |
| | hir::ItemKind::Ty(..) |
| | hir::ItemKind::Union(..) |
| | hir::ItemKind::Existential(..) |
| | hir::ItemKind::ExternCrate(..) |
| | hir::ItemKind::ForeignMod(..) |
| | hir::ItemKind::Impl(..) |
| | hir::ItemKind::Use(..) => {}, |
| }; |
| } |
| |
| fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, impl_item: &'tcx hir::ImplItem) { |
| use rustc::ty::{ImplContainer, TraitContainer}; |
| if is_executable(cx) { |
| return; |
| } |
| |
| // If the item being implemented is not exported, then we don't need #[inline] |
| if !cx.access_levels.is_exported(impl_item.hir_id) { |
| return; |
| } |
| |
| let desc = match impl_item.node { |
| hir::ImplItemKind::Method(..) => "a method", |
| hir::ImplItemKind::Const(..) | hir::ImplItemKind::Type(_) | hir::ImplItemKind::Existential(_) => return, |
| }; |
| |
| let def_id = cx.tcx.hir().local_def_id_from_hir_id(impl_item.hir_id); |
| let trait_def_id = match cx.tcx.associated_item(def_id).container { |
| TraitContainer(cid) => Some(cid), |
| ImplContainer(cid) => cx.tcx.impl_trait_ref(cid).map(|t| t.def_id), |
| }; |
| |
| if let Some(trait_def_id) = trait_def_id { |
| if cx.tcx.hir().as_local_node_id(trait_def_id).is_some() && !cx.access_levels.is_exported(impl_item.hir_id) |
| { |
| // If a trait is being implemented for an item, and the |
| // trait is not exported, we don't need #[inline] |
| return; |
| } |
| } |
| |
| check_missing_inline_attrs(cx, &impl_item.attrs, impl_item.span, desc); |
| } |
| } |