| //! checks for attributes |
| |
| use crate::utils::{ |
| first_line_of_span, is_present_in_source, match_def_path, paths, snippet_opt, span_lint, span_lint_and_help, |
| span_lint_and_sugg, span_lint_and_then, without_block_comments, |
| }; |
| use if_chain::if_chain; |
| use rustc_ast::util::lev_distance::find_best_match_for_name; |
| use rustc_ast::{AttrKind, AttrStyle, Attribute, Lit, LitKind, MetaItemKind, NestedMetaItem}; |
| use rustc_errors::Applicability; |
| use rustc_hir::{ |
| Block, Expr, ExprKind, ImplItem, ImplItemKind, Item, ItemKind, StmtKind, TraitFn, TraitItem, TraitItemKind, |
| }; |
| use rustc_lint::{CheckLintNameResult, EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext}; |
| use rustc_middle::lint::in_external_macro; |
| use rustc_middle::ty; |
| use rustc_session::{declare_lint_pass, declare_tool_lint}; |
| use rustc_span::source_map::Span; |
| use rustc_span::symbol::{Symbol, SymbolStr}; |
| use semver::Version; |
| |
| static UNIX_SYSTEMS: &[&str] = &[ |
| "android", |
| "dragonfly", |
| "emscripten", |
| "freebsd", |
| "fuchsia", |
| "haiku", |
| "illumos", |
| "ios", |
| "l4re", |
| "linux", |
| "macos", |
| "netbsd", |
| "openbsd", |
| "redox", |
| "solaris", |
| "vxworks", |
| ]; |
| |
| // NOTE: windows is excluded from the list because it's also a valid target family. |
| static NON_UNIX_SYSTEMS: &[&str] = &["cloudabi", "hermit", "none", "wasi"]; |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for items annotated with `#[inline(always)]`, |
| /// unless the annotated function is empty or simply panics. |
| /// |
| /// **Why is this bad?** While there are valid uses of this annotation (and once |
| /// you know when to use it, by all means `allow` this lint), it's a common |
| /// newbie-mistake to pepper one's code with it. |
| /// |
| /// As a rule of thumb, before slapping `#[inline(always)]` on a function, |
| /// measure if that additional function call really affects your runtime profile |
| /// sufficiently to make up for the increase in compile time. |
| /// |
| /// **Known problems:** False positives, big time. This lint is meant to be |
| /// deactivated by everyone doing serious performance work. This means having |
| /// done the measurement. |
| /// |
| /// **Example:** |
| /// ```ignore |
| /// #[inline(always)] |
| /// fn not_quite_hot_code(..) { ... } |
| /// ``` |
| pub INLINE_ALWAYS, |
| pedantic, |
| "use of `#[inline(always)]`" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for `extern crate` and `use` items annotated with |
| /// lint attributes. |
| /// |
| /// This lint permits `#[allow(unused_imports)]`, `#[allow(deprecated)]`, |
| /// `#[allow(unreachable_pub)]`, `#[allow(clippy::wildcard_imports)]` and |
| /// `#[allow(clippy::enum_glob_use)]` on `use` items and `#[allow(unused_imports)]` on |
| /// `extern crate` items with a `#[macro_use]` attribute. |
| /// |
| /// **Why is this bad?** Lint attributes have no effect on crate imports. Most |
| /// likely a `!` was forgotten. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// ```ignore |
| /// // Bad |
| /// #[deny(dead_code)] |
| /// extern crate foo; |
| /// #[forbid(dead_code)] |
| /// use foo::bar; |
| /// |
| /// // Ok |
| /// #[allow(unused_imports)] |
| /// use foo::baz; |
| /// #[allow(unused_imports)] |
| /// #[macro_use] |
| /// extern crate baz; |
| /// ``` |
| pub USELESS_ATTRIBUTE, |
| correctness, |
| "use of lint attributes on `extern crate` items" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for `#[deprecated]` annotations with a `since` |
| /// field that is not a valid semantic version. |
| /// |
| /// **Why is this bad?** For checking the version of the deprecation, it must be |
| /// a valid semver. Failing that, the contained information is useless. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// ```rust |
| /// #[deprecated(since = "forever")] |
| /// fn something_else() { /* ... */ } |
| /// ``` |
| pub DEPRECATED_SEMVER, |
| correctness, |
| "use of `#[deprecated(since = \"x\")]` where x is not semver" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for empty lines after outer attributes |
| /// |
| /// **Why is this bad?** |
| /// Most likely the attribute was meant to be an inner attribute using a '!'. |
| /// If it was meant to be an outer attribute, then the following item |
| /// should not be separated by empty lines. |
| /// |
| /// **Known problems:** Can cause false positives. |
| /// |
| /// From the clippy side it's difficult to detect empty lines between an attributes and the |
| /// following item because empty lines and comments are not part of the AST. The parsing |
| /// currently works for basic cases but is not perfect. |
| /// |
| /// **Example:** |
| /// ```rust |
| /// // Good (as inner attribute) |
| /// #![inline(always)] |
| /// |
| /// fn this_is_fine() { } |
| /// |
| /// // Bad |
| /// #[inline(always)] |
| /// |
| /// fn not_quite_good_code() { } |
| /// |
| /// // Good (as outer attribute) |
| /// #[inline(always)] |
| /// fn this_is_fine_too() { } |
| /// ``` |
| pub EMPTY_LINE_AFTER_OUTER_ATTR, |
| nursery, |
| "empty line after outer attribute" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for `allow`/`warn`/`deny`/`forbid` attributes with scoped clippy |
| /// lints and if those lints exist in clippy. If there is an uppercase letter in the lint name |
| /// (not the tool name) and a lowercase version of this lint exists, it will suggest to lowercase |
| /// the lint name. |
| /// |
| /// **Why is this bad?** A lint attribute with a mistyped lint name won't have an effect. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// Bad: |
| /// ```rust |
| /// #![warn(if_not_els)] |
| /// #![deny(clippy::All)] |
| /// ``` |
| /// |
| /// Good: |
| /// ```rust |
| /// #![warn(if_not_else)] |
| /// #![deny(clippy::all)] |
| /// ``` |
| pub UNKNOWN_CLIPPY_LINTS, |
| style, |
| "unknown_lints for scoped Clippy lints" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for `warn`/`deny`/`forbid` attributes targeting the whole clippy::restriction category. |
| /// |
| /// **Why is this bad?** Restriction lints sometimes are in contrast with other lints or even go against idiomatic rust. |
| /// These lints should only be enabled on a lint-by-lint basis and with careful consideration. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// Bad: |
| /// ```rust |
| /// #![deny(clippy::restriction)] |
| /// ``` |
| /// |
| /// Good: |
| /// ```rust |
| /// #![deny(clippy::as_conversions)] |
| /// ``` |
| pub BLANKET_CLIPPY_RESTRICTION_LINTS, |
| style, |
| "enabling the complete restriction group" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for `#[cfg_attr(rustfmt, rustfmt_skip)]` and suggests to replace it |
| /// with `#[rustfmt::skip]`. |
| /// |
| /// **Why is this bad?** Since tool_attributes ([rust-lang/rust#44690](https://github.com/rust-lang/rust/issues/44690)) |
| /// are stable now, they should be used instead of the old `cfg_attr(rustfmt)` attributes. |
| /// |
| /// **Known problems:** This lint doesn't detect crate level inner attributes, because they get |
| /// processed before the PreExpansionPass lints get executed. See |
| /// [#3123](https://github.com/rust-lang/rust-clippy/pull/3123#issuecomment-422321765) |
| /// |
| /// **Example:** |
| /// |
| /// Bad: |
| /// ```rust |
| /// #[cfg_attr(rustfmt, rustfmt_skip)] |
| /// fn main() { } |
| /// ``` |
| /// |
| /// Good: |
| /// ```rust |
| /// #[rustfmt::skip] |
| /// fn main() { } |
| /// ``` |
| pub DEPRECATED_CFG_ATTR, |
| complexity, |
| "usage of `cfg_attr(rustfmt)` instead of tool attributes" |
| } |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks for cfg attributes having operating systems used in target family position. |
| /// |
| /// **Why is this bad?** The configuration option will not be recognised and the related item will not be included |
| /// by the conditional compilation engine. |
| /// |
| /// **Known problems:** None. |
| /// |
| /// **Example:** |
| /// |
| /// Bad: |
| /// ```rust |
| /// #[cfg(linux)] |
| /// fn conditional() { } |
| /// ``` |
| /// |
| /// Good: |
| /// ```rust |
| /// #[cfg(target_os = "linux")] |
| /// fn conditional() { } |
| /// ``` |
| /// |
| /// Or: |
| /// ```rust |
| /// #[cfg(unix)] |
| /// fn conditional() { } |
| /// ``` |
| /// Check the [Rust Reference](https://doc.rust-lang.org/reference/conditional-compilation.html#target_os) for more details. |
| pub MISMATCHED_TARGET_OS, |
| correctness, |
| "usage of `cfg(operating_system)` instead of `cfg(target_os = \"operating_system\")`" |
| } |
| |
| declare_lint_pass!(Attributes => [ |
| INLINE_ALWAYS, |
| DEPRECATED_SEMVER, |
| USELESS_ATTRIBUTE, |
| UNKNOWN_CLIPPY_LINTS, |
| BLANKET_CLIPPY_RESTRICTION_LINTS, |
| ]); |
| |
| impl<'tcx> LateLintPass<'tcx> for Attributes { |
| fn check_attribute(&mut self, cx: &LateContext<'tcx>, attr: &'tcx Attribute) { |
| if let Some(items) = &attr.meta_item_list() { |
| if let Some(ident) = attr.ident() { |
| let ident = &*ident.as_str(); |
| match ident { |
| "allow" | "warn" | "deny" | "forbid" => { |
| check_clippy_lint_names(cx, ident, items); |
| }, |
| _ => {}, |
| } |
| if items.is_empty() || !attr.has_name(sym!(deprecated)) { |
| return; |
| } |
| for item in items { |
| if_chain! { |
| if let NestedMetaItem::MetaItem(mi) = &item; |
| if let MetaItemKind::NameValue(lit) = &mi.kind; |
| if mi.has_name(sym!(since)); |
| then { |
| check_semver(cx, item.span(), lit); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) { |
| if is_relevant_item(cx, item) { |
| check_attrs(cx, item.span, item.ident.name, &item.attrs) |
| } |
| match item.kind { |
| ItemKind::ExternCrate(..) | ItemKind::Use(..) => { |
| let skip_unused_imports = item.attrs.iter().any(|attr| attr.has_name(sym!(macro_use))); |
| |
| for attr in item.attrs { |
| if in_external_macro(cx.sess(), attr.span) { |
| return; |
| } |
| if let Some(lint_list) = &attr.meta_item_list() { |
| if let Some(ident) = attr.ident() { |
| match &*ident.as_str() { |
| "allow" | "warn" | "deny" | "forbid" => { |
| // permit `unused_imports`, `deprecated`, `unreachable_pub`, |
| // `clippy::wildcard_imports`, and `clippy::enum_glob_use` for `use` items |
| // and `unused_imports` for `extern crate` items with `macro_use` |
| for lint in lint_list { |
| match item.kind { |
| ItemKind::Use(..) => { |
| if is_word(lint, sym!(unused_imports)) |
| || is_word(lint, sym!(deprecated)) |
| || is_word(lint, sym!(unreachable_pub)) |
| || is_word(lint, sym!(unused)) |
| || extract_clippy_lint(lint) |
| .map_or(false, |s| s == "wildcard_imports") |
| || extract_clippy_lint(lint).map_or(false, |s| s == "enum_glob_use") |
| { |
| return; |
| } |
| }, |
| ItemKind::ExternCrate(..) => { |
| if is_word(lint, sym!(unused_imports)) && skip_unused_imports { |
| return; |
| } |
| if is_word(lint, sym!(unused_extern_crates)) { |
| return; |
| } |
| }, |
| _ => {}, |
| } |
| } |
| let line_span = first_line_of_span(cx, attr.span); |
| |
| if let Some(mut sugg) = snippet_opt(cx, line_span) { |
| if sugg.contains("#[") { |
| span_lint_and_then( |
| cx, |
| USELESS_ATTRIBUTE, |
| line_span, |
| "useless lint attribute", |
| |diag| { |
| sugg = sugg.replacen("#[", "#![", 1); |
| diag.span_suggestion( |
| line_span, |
| "if you just forgot a `!`, use", |
| sugg, |
| Applicability::MaybeIncorrect, |
| ); |
| }, |
| ); |
| } |
| } |
| }, |
| _ => {}, |
| } |
| } |
| } |
| } |
| }, |
| _ => {}, |
| } |
| } |
| |
| fn check_impl_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx ImplItem<'_>) { |
| if is_relevant_impl(cx, item) { |
| check_attrs(cx, item.span, item.ident.name, &item.attrs) |
| } |
| } |
| |
| fn check_trait_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx TraitItem<'_>) { |
| if is_relevant_trait(cx, item) { |
| check_attrs(cx, item.span, item.ident.name, &item.attrs) |
| } |
| } |
| } |
| |
| /// Returns the lint name if it is clippy lint. |
| fn extract_clippy_lint(lint: &NestedMetaItem) -> Option<SymbolStr> { |
| if_chain! { |
| if let Some(meta_item) = lint.meta_item(); |
| if meta_item.path.segments.len() > 1; |
| if let tool_name = meta_item.path.segments[0].ident; |
| if tool_name.as_str() == "clippy"; |
| let lint_name = meta_item.path.segments.last().unwrap().ident.name; |
| then { |
| return Some(lint_name.as_str()); |
| } |
| } |
| None |
| } |
| |
| fn check_clippy_lint_names(cx: &LateContext<'_>, ident: &str, items: &[NestedMetaItem]) { |
| let lint_store = cx.lints(); |
| for lint in items { |
| if let Some(lint_name) = extract_clippy_lint(lint) { |
| if let CheckLintNameResult::Tool(Err((None, _))) = |
| lint_store.check_lint_name(&lint_name, Some(sym!(clippy))) |
| { |
| span_lint_and_then( |
| cx, |
| UNKNOWN_CLIPPY_LINTS, |
| lint.span(), |
| &format!("unknown clippy lint: clippy::{}", lint_name), |
| |diag| { |
| let name_lower = lint_name.to_lowercase(); |
| let symbols = lint_store |
| .get_lints() |
| .iter() |
| .map(|l| Symbol::intern(&l.name_lower())) |
| .collect::<Vec<_>>(); |
| let sugg = find_best_match_for_name( |
| symbols.iter(), |
| Symbol::intern(&format!("clippy::{}", name_lower)), |
| None, |
| ); |
| if lint_name.chars().any(char::is_uppercase) |
| && lint_store.find_lints(&format!("clippy::{}", name_lower)).is_ok() |
| { |
| diag.span_suggestion( |
| lint.span(), |
| "lowercase the lint name", |
| format!("clippy::{}", name_lower), |
| Applicability::MachineApplicable, |
| ); |
| } else if let Some(sugg) = sugg { |
| diag.span_suggestion( |
| lint.span(), |
| "did you mean", |
| sugg.to_string(), |
| Applicability::MachineApplicable, |
| ); |
| } |
| }, |
| ); |
| } else if lint_name == "restriction" && ident != "allow" { |
| span_lint_and_help( |
| cx, |
| BLANKET_CLIPPY_RESTRICTION_LINTS, |
| lint.span(), |
| "restriction lints are not meant to be all enabled", |
| None, |
| "try enabling only the lints you really need", |
| ); |
| } |
| } |
| } |
| } |
| |
| fn is_relevant_item(cx: &LateContext<'_>, item: &Item<'_>) -> bool { |
| if let ItemKind::Fn(_, _, eid) = item.kind { |
| is_relevant_expr(cx, cx.tcx.typeck_body(eid), &cx.tcx.hir().body(eid).value) |
| } else { |
| true |
| } |
| } |
| |
| fn is_relevant_impl(cx: &LateContext<'_>, item: &ImplItem<'_>) -> bool { |
| match item.kind { |
| ImplItemKind::Fn(_, eid) => is_relevant_expr(cx, cx.tcx.typeck_body(eid), &cx.tcx.hir().body(eid).value), |
| _ => false, |
| } |
| } |
| |
| fn is_relevant_trait(cx: &LateContext<'_>, item: &TraitItem<'_>) -> bool { |
| match item.kind { |
| TraitItemKind::Fn(_, TraitFn::Required(_)) => true, |
| TraitItemKind::Fn(_, TraitFn::Provided(eid)) => { |
| is_relevant_expr(cx, cx.tcx.typeck_body(eid), &cx.tcx.hir().body(eid).value) |
| }, |
| _ => false, |
| } |
| } |
| |
| fn is_relevant_block(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_>, block: &Block<'_>) -> bool { |
| block.stmts.first().map_or( |
| block |
| .expr |
| .as_ref() |
| .map_or(false, |e| is_relevant_expr(cx, typeck_results, e)), |
| |stmt| match &stmt.kind { |
| StmtKind::Local(_) => true, |
| StmtKind::Expr(expr) | StmtKind::Semi(expr) => is_relevant_expr(cx, typeck_results, expr), |
| _ => false, |
| }, |
| ) |
| } |
| |
| fn is_relevant_expr(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_>, expr: &Expr<'_>) -> bool { |
| match &expr.kind { |
| ExprKind::Block(block, _) => is_relevant_block(cx, typeck_results, block), |
| ExprKind::Ret(Some(e)) => is_relevant_expr(cx, typeck_results, e), |
| ExprKind::Ret(None) | ExprKind::Break(_, None) => false, |
| ExprKind::Call(path_expr, _) => { |
| if let ExprKind::Path(qpath) = &path_expr.kind { |
| typeck_results |
| .qpath_res(qpath, path_expr.hir_id) |
| .opt_def_id() |
| .map_or(true, |fun_id| !match_def_path(cx, fun_id, &paths::BEGIN_PANIC)) |
| } else { |
| true |
| } |
| }, |
| _ => true, |
| } |
| } |
| |
| fn check_attrs(cx: &LateContext<'_>, span: Span, name: Symbol, attrs: &[Attribute]) { |
| if span.from_expansion() { |
| return; |
| } |
| |
| for attr in attrs { |
| if let Some(values) = attr.meta_item_list() { |
| if values.len() != 1 || !attr.has_name(sym!(inline)) { |
| continue; |
| } |
| if is_word(&values[0], sym!(always)) { |
| span_lint( |
| cx, |
| INLINE_ALWAYS, |
| attr.span, |
| &format!( |
| "you have declared `#[inline(always)]` on `{}`. This is usually a bad idea", |
| name |
| ), |
| ); |
| } |
| } |
| } |
| } |
| |
| fn check_semver(cx: &LateContext<'_>, span: Span, lit: &Lit) { |
| if let LitKind::Str(is, _) = lit.kind { |
| if Version::parse(&is.as_str()).is_ok() { |
| return; |
| } |
| } |
| span_lint( |
| cx, |
| DEPRECATED_SEMVER, |
| span, |
| "the since field must contain a semver-compliant version", |
| ); |
| } |
| |
| fn is_word(nmi: &NestedMetaItem, expected: Symbol) -> bool { |
| if let NestedMetaItem::MetaItem(mi) = &nmi { |
| mi.is_word() && mi.has_name(expected) |
| } else { |
| false |
| } |
| } |
| |
| declare_lint_pass!(EarlyAttributes => [ |
| DEPRECATED_CFG_ATTR, |
| MISMATCHED_TARGET_OS, |
| EMPTY_LINE_AFTER_OUTER_ATTR, |
| ]); |
| |
| impl EarlyLintPass for EarlyAttributes { |
| fn check_item(&mut self, cx: &EarlyContext<'_>, item: &rustc_ast::Item) { |
| check_empty_line_after_outer_attr(cx, item); |
| } |
| |
| fn check_attribute(&mut self, cx: &EarlyContext<'_>, attr: &Attribute) { |
| check_deprecated_cfg_attr(cx, attr); |
| check_mismatched_target_os(cx, attr); |
| } |
| } |
| |
| fn check_empty_line_after_outer_attr(cx: &EarlyContext<'_>, item: &rustc_ast::Item) { |
| for attr in &item.attrs { |
| let attr_item = if let AttrKind::Normal(ref attr) = attr.kind { |
| attr |
| } else { |
| return; |
| }; |
| |
| if attr.style == AttrStyle::Outer { |
| if attr_item.args.inner_tokens().is_empty() || !is_present_in_source(cx, attr.span) { |
| return; |
| } |
| |
| let begin_of_attr_to_item = Span::new(attr.span.lo(), item.span.lo(), item.span.ctxt()); |
| let end_of_attr_to_item = Span::new(attr.span.hi(), item.span.lo(), item.span.ctxt()); |
| |
| if let Some(snippet) = snippet_opt(cx, end_of_attr_to_item) { |
| let lines = snippet.split('\n').collect::<Vec<_>>(); |
| let lines = without_block_comments(lines); |
| |
| if lines.iter().filter(|l| l.trim().is_empty()).count() > 2 { |
| span_lint( |
| cx, |
| EMPTY_LINE_AFTER_OUTER_ATTR, |
| begin_of_attr_to_item, |
| "found an empty line after an outer attribute. \ |
| Perhaps you forgot to add a `!` to make it an inner attribute?", |
| ); |
| } |
| } |
| } |
| } |
| } |
| |
| fn check_deprecated_cfg_attr(cx: &EarlyContext<'_>, attr: &Attribute) { |
| if_chain! { |
| // check cfg_attr |
| if attr.has_name(sym!(cfg_attr)); |
| if let Some(items) = attr.meta_item_list(); |
| if items.len() == 2; |
| // check for `rustfmt` |
| if let Some(feature_item) = items[0].meta_item(); |
| if feature_item.has_name(sym!(rustfmt)); |
| // check for `rustfmt_skip` and `rustfmt::skip` |
| if let Some(skip_item) = &items[1].meta_item(); |
| if skip_item.has_name(sym!(rustfmt_skip)) || |
| skip_item.path.segments.last().expect("empty path in attribute").ident.name == sym!(skip); |
| // Only lint outer attributes, because custom inner attributes are unstable |
| // Tracking issue: https://github.com/rust-lang/rust/issues/54726 |
| if let AttrStyle::Outer = attr.style; |
| then { |
| span_lint_and_sugg( |
| cx, |
| DEPRECATED_CFG_ATTR, |
| attr.span, |
| "`cfg_attr` is deprecated for rustfmt and got replaced by tool attributes", |
| "use", |
| "#[rustfmt::skip]".to_string(), |
| Applicability::MachineApplicable, |
| ); |
| } |
| } |
| } |
| |
| fn check_mismatched_target_os(cx: &EarlyContext<'_>, attr: &Attribute) { |
| fn find_os(name: &str) -> Option<&'static str> { |
| UNIX_SYSTEMS |
| .iter() |
| .chain(NON_UNIX_SYSTEMS.iter()) |
| .find(|&&os| os == name) |
| .copied() |
| } |
| |
| fn is_unix(name: &str) -> bool { |
| UNIX_SYSTEMS.iter().any(|&os| os == name) |
| } |
| |
| fn find_mismatched_target_os(items: &[NestedMetaItem]) -> Vec<(&str, Span)> { |
| let mut mismatched = Vec::new(); |
| |
| for item in items { |
| if let NestedMetaItem::MetaItem(meta) = item { |
| match &meta.kind { |
| MetaItemKind::List(list) => { |
| mismatched.extend(find_mismatched_target_os(&list)); |
| }, |
| MetaItemKind::Word => { |
| if_chain! { |
| if let Some(ident) = meta.ident(); |
| if let Some(os) = find_os(&*ident.name.as_str()); |
| then { |
| mismatched.push((os, ident.span)); |
| } |
| } |
| }, |
| _ => {}, |
| } |
| } |
| } |
| |
| mismatched |
| } |
| |
| if_chain! { |
| if attr.has_name(sym!(cfg)); |
| if let Some(list) = attr.meta_item_list(); |
| let mismatched = find_mismatched_target_os(&list); |
| if !mismatched.is_empty(); |
| then { |
| let mess = "operating system used in target family position"; |
| |
| span_lint_and_then(cx, MISMATCHED_TARGET_OS, attr.span, &mess, |diag| { |
| // Avoid showing the unix suggestion multiple times in case |
| // we have more than one mismatch for unix-like systems |
| let mut unix_suggested = false; |
| |
| for (os, span) in mismatched { |
| let sugg = format!("target_os = \"{}\"", os); |
| diag.span_suggestion(span, "try", sugg, Applicability::MaybeIncorrect); |
| |
| if !unix_suggested && is_unix(os) { |
| diag.help("Did you mean `unix`?"); |
| unix_suggested = true; |
| } |
| } |
| }); |
| } |
| } |
| } |
