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Diffstat (limited to 'src/tools/clippy/clippy_lints/src/utils/internal_lints.rs')
| -rw-r--r-- | src/tools/clippy/clippy_lints/src/utils/internal_lints.rs | 1436 |
1 files changed, 1436 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs new file mode 100644 index 000000000..b30965329 --- /dev/null +++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs @@ -0,0 +1,1436 @@ +use crate::utils::internal_lints::metadata_collector::is_deprecated_lint; +use clippy_utils::consts::{constant_simple, Constant}; +use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then}; +use clippy_utils::macros::root_macro_call_first_node; +use clippy_utils::source::snippet; +use clippy_utils::ty::match_type; +use clippy_utils::{ + def_path_res, higher, is_else_clause, is_expn_of, is_expr_path_def_path, is_lint_allowed, match_def_path, + method_calls, paths, peel_blocks_with_stmt, SpanlessEq, +}; +use if_chain::if_chain; +use rustc_ast as ast; +use rustc_ast::ast::{Crate, ItemKind, LitKind, ModKind, NodeId}; +use rustc_ast::visit::FnKind; +use rustc_data_structures::fx::{FxHashMap, FxHashSet}; +use rustc_errors::Applicability; +use rustc_hir as hir; +use rustc_hir::def::{DefKind, Res}; +use rustc_hir::def_id::DefId; +use rustc_hir::hir_id::CRATE_HIR_ID; +use rustc_hir::intravisit::Visitor; +use rustc_hir::{ + BinOpKind, Block, Closure, Expr, ExprKind, HirId, Item, Local, MutTy, Mutability, Node, Path, Stmt, StmtKind, Ty, + TyKind, UnOp, +}; +use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext}; +use rustc_middle::hir::nested_filter; +use rustc_middle::mir::interpret::ConstValue; +use rustc_middle::ty::{self, fast_reject::SimplifiedTypeGen, subst::GenericArgKind, FloatTy}; +use rustc_semver::RustcVersion; +use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass}; +use rustc_span::source_map::Spanned; +use rustc_span::symbol::Symbol; +use rustc_span::{sym, BytePos, Span}; +use rustc_typeck::hir_ty_to_ty; + +use std::borrow::{Borrow, Cow}; + +#[cfg(feature = "internal")] +pub mod metadata_collector; + +declare_clippy_lint! { + /// ### What it does + /// Checks for various things we like to keep tidy in clippy. + /// + /// ### Why is this bad? + /// We like to pretend we're an example of tidy code. + /// + /// ### Example + /// Wrong ordering of the util::paths constants. + pub CLIPPY_LINTS_INTERNAL, + internal, + "various things that will negatively affect your clippy experience" +} + +declare_clippy_lint! { + /// ### What it does + /// Ensures every lint is associated to a `LintPass`. + /// + /// ### Why is this bad? + /// The compiler only knows lints via a `LintPass`. Without + /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not + /// know the name of the lint. + /// + /// ### Known problems + /// Only checks for lints associated using the + /// `declare_lint_pass!`, `impl_lint_pass!`, and `lint_array!` macros. + /// + /// ### Example + /// ```rust,ignore + /// declare_lint! { pub LINT_1, ... } + /// declare_lint! { pub LINT_2, ... } + /// declare_lint! { pub FORGOTTEN_LINT, ... } + /// // ... + /// declare_lint_pass!(Pass => [LINT_1, LINT_2]); + /// // missing FORGOTTEN_LINT + /// ``` + pub LINT_WITHOUT_LINT_PASS, + internal, + "declaring a lint without associating it in a LintPass" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for calls to `cx.span_lint*` and suggests to use the `utils::*` + /// variant of the function. + /// + /// ### Why is this bad? + /// The `utils::*` variants also add a link to the Clippy documentation to the + /// warning/error messages. + /// + /// ### Example + /// ```rust,ignore + /// cx.span_lint(LINT_NAME, "message"); + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// utils::span_lint(cx, LINT_NAME, "message"); + /// ``` + pub COMPILER_LINT_FUNCTIONS, + internal, + "usage of the lint functions of the compiler instead of the utils::* variant" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for calls to `cx.outer().expn_data()` and suggests to use + /// the `cx.outer_expn_data()` + /// + /// ### Why is this bad? + /// `cx.outer_expn_data()` is faster and more concise. + /// + /// ### Example + /// ```rust,ignore + /// expr.span.ctxt().outer().expn_data() + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// expr.span.ctxt().outer_expn_data() + /// ``` + pub OUTER_EXPN_EXPN_DATA, + internal, + "using `cx.outer_expn().expn_data()` instead of `cx.outer_expn_data()`" +} + +declare_clippy_lint! { + /// ### What it does + /// Not an actual lint. This lint is only meant for testing our customized internal compiler + /// error message by calling `panic`. + /// + /// ### Why is this bad? + /// ICE in large quantities can damage your teeth + /// + /// ### Example + /// ```rust,ignore + /// 🍦🍦🍦🍦🍦 + /// ``` + pub PRODUCE_ICE, + internal, + "this message should not appear anywhere as we ICE before and don't emit the lint" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for cases of an auto-generated lint without an updated description, + /// i.e. `default lint description`. + /// + /// ### Why is this bad? + /// Indicates that the lint is not finished. + /// + /// ### Example + /// ```rust,ignore + /// declare_lint! { pub COOL_LINT, nursery, "default lint description" } + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// declare_lint! { pub COOL_LINT, nursery, "a great new lint" } + /// ``` + pub DEFAULT_LINT, + internal, + "found 'default lint description' in a lint declaration" +} + +declare_clippy_lint! { + /// ### What it does + /// Lints `span_lint_and_then` function calls, where the + /// closure argument has only one statement and that statement is a method + /// call to `span_suggestion`, `span_help`, `span_note` (using the same + /// span), `help` or `note`. + /// + /// These usages of `span_lint_and_then` should be replaced with one of the + /// wrapper functions `span_lint_and_sugg`, span_lint_and_help`, or + /// `span_lint_and_note`. + /// + /// ### Why is this bad? + /// Using the wrapper `span_lint_and_*` functions, is more + /// convenient, readable and less error prone. + /// + /// ### Example + /// ```rust,ignore + /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| { + /// diag.span_suggestion( + /// expr.span, + /// help_msg, + /// sugg.to_string(), + /// Applicability::MachineApplicable, + /// ); + /// }); + /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| { + /// diag.span_help(expr.span, help_msg); + /// }); + /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| { + /// diag.help(help_msg); + /// }); + /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| { + /// diag.span_note(expr.span, note_msg); + /// }); + /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| { + /// diag.note(note_msg); + /// }); + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// span_lint_and_sugg( + /// cx, + /// TEST_LINT, + /// expr.span, + /// lint_msg, + /// help_msg, + /// sugg.to_string(), + /// Applicability::MachineApplicable, + /// ); + /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), help_msg); + /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, None, help_msg); + /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), note_msg); + /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, None, note_msg); + /// ``` + pub COLLAPSIBLE_SPAN_LINT_CALLS, + internal, + "found collapsible `span_lint_and_then` calls" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for calls to `utils::match_type()` on a type diagnostic item + /// and suggests to use `utils::is_type_diagnostic_item()` instead. + /// + /// ### Why is this bad? + /// `utils::is_type_diagnostic_item()` does not require hardcoded paths. + /// + /// ### Example + /// ```rust,ignore + /// utils::match_type(cx, ty, &paths::VEC) + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// utils::is_type_diagnostic_item(cx, ty, sym::Vec) + /// ``` + pub MATCH_TYPE_ON_DIAGNOSTIC_ITEM, + internal, + "using `utils::match_type()` instead of `utils::is_type_diagnostic_item()`" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks the paths module for invalid paths. + /// + /// ### Why is this bad? + /// It indicates a bug in the code. + /// + /// ### Example + /// None. + pub INVALID_PATHS, + internal, + "invalid path" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for interning symbols that have already been pre-interned and defined as constants. + /// + /// ### Why is this bad? + /// It's faster and easier to use the symbol constant. + /// + /// ### Example + /// ```rust,ignore + /// let _ = sym!(f32); + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// let _ = sym::f32; + /// ``` + pub INTERNING_DEFINED_SYMBOL, + internal, + "interning a symbol that is pre-interned and defined as a constant" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for unnecessary conversion from Symbol to a string. + /// + /// ### Why is this bad? + /// It's faster use symbols directly instead of strings. + /// + /// ### Example + /// ```rust,ignore + /// symbol.as_str() == "clippy"; + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// symbol == sym::clippy; + /// ``` + pub UNNECESSARY_SYMBOL_STR, + internal, + "unnecessary conversion between Symbol and string" +} + +declare_clippy_lint! { + /// Finds unidiomatic usage of `if_chain!` + pub IF_CHAIN_STYLE, + internal, + "non-idiomatic `if_chain!` usage" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for invalid `clippy::version` attributes. + /// + /// Valid values are: + /// * "pre 1.29.0" + /// * any valid semantic version + pub INVALID_CLIPPY_VERSION_ATTRIBUTE, + internal, + "found an invalid `clippy::version` attribute" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for declared clippy lints without the `clippy::version` attribute. + /// + pub MISSING_CLIPPY_VERSION_ATTRIBUTE, + internal, + "found clippy lint without `clippy::version` attribute" +} + +declare_clippy_lint! { + /// ### What it does + /// Check that the `extract_msrv_attr!` macro is used, when a lint has a MSRV. + /// + pub MISSING_MSRV_ATTR_IMPL, + internal, + "checking if all necessary steps were taken when adding a MSRV to a lint" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for cases of an auto-generated deprecated lint without an updated reason, + /// i.e. `"default deprecation note"`. + /// + /// ### Why is this bad? + /// Indicates that the documentation is incomplete. + /// + /// ### Example + /// ```rust,ignore + /// declare_deprecated_lint! { + /// /// ### What it does + /// /// Nothing. This lint has been deprecated. + /// /// + /// /// ### Deprecation reason + /// /// TODO + /// #[clippy::version = "1.63.0"] + /// pub COOL_LINT, + /// "default deprecation note" + /// } + /// ``` + /// + /// Use instead: + /// ```rust,ignore + /// declare_deprecated_lint! { + /// /// ### What it does + /// /// Nothing. This lint has been deprecated. + /// /// + /// /// ### Deprecation reason + /// /// This lint has been replaced by `cooler_lint` + /// #[clippy::version = "1.63.0"] + /// pub COOL_LINT, + /// "this lint has been replaced by `cooler_lint`" + /// } + /// ``` + pub DEFAULT_DEPRECATION_REASON, + internal, + "found 'default deprecation note' in a deprecated lint declaration" +} + +declare_lint_pass!(ClippyLintsInternal => [CLIPPY_LINTS_INTERNAL]); + +impl EarlyLintPass for ClippyLintsInternal { + fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &Crate) { + if let Some(utils) = krate.items.iter().find(|item| item.ident.name.as_str() == "utils") { + if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = utils.kind { + if let Some(paths) = items.iter().find(|item| item.ident.name.as_str() == "paths") { + if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = paths.kind { + let mut last_name: Option<&str> = None; + for item in items { + let name = item.ident.as_str(); + if let Some(last_name) = last_name { + if *last_name > *name { + span_lint( + cx, + CLIPPY_LINTS_INTERNAL, + item.span, + "this constant should be before the previous constant due to lexical \ + ordering", + ); + } + } + last_name = Some(name); + } + } + } + } + } + } +} + +#[derive(Clone, Debug, Default)] +pub struct LintWithoutLintPass { + declared_lints: FxHashMap<Symbol, Span>, + registered_lints: FxHashSet<Symbol>, +} + +impl_lint_pass!(LintWithoutLintPass => [DEFAULT_LINT, LINT_WITHOUT_LINT_PASS, INVALID_CLIPPY_VERSION_ATTRIBUTE, MISSING_CLIPPY_VERSION_ATTRIBUTE, DEFAULT_DEPRECATION_REASON]); + +impl<'tcx> LateLintPass<'tcx> for LintWithoutLintPass { + fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) { + if is_lint_allowed(cx, DEFAULT_LINT, item.hir_id()) + || is_lint_allowed(cx, DEFAULT_DEPRECATION_REASON, item.hir_id()) + { + return; + } + + if let hir::ItemKind::Static(ty, Mutability::Not, body_id) = item.kind { + let is_lint_ref_ty = is_lint_ref_type(cx, ty); + if is_deprecated_lint(cx, ty) || is_lint_ref_ty { + check_invalid_clippy_version_attribute(cx, item); + + let expr = &cx.tcx.hir().body(body_id).value; + let fields; + if is_lint_ref_ty { + if let ExprKind::AddrOf(_, _, inner_exp) = expr.kind + && let ExprKind::Struct(_, struct_fields, _) = inner_exp.kind { + fields = struct_fields; + } else { + return; + } + } else if let ExprKind::Struct(_, struct_fields, _) = expr.kind { + fields = struct_fields; + } else { + return; + } + + let field = fields + .iter() + .find(|f| f.ident.as_str() == "desc") + .expect("lints must have a description field"); + + if let ExprKind::Lit(Spanned { + node: LitKind::Str(ref sym, _), + .. + }) = field.expr.kind + { + let sym_str = sym.as_str(); + if is_lint_ref_ty { + if sym_str == "default lint description" { + span_lint( + cx, + DEFAULT_LINT, + item.span, + &format!("the lint `{}` has the default lint description", item.ident.name), + ); + } + + self.declared_lints.insert(item.ident.name, item.span); + } else if sym_str == "default deprecation note" { + span_lint( + cx, + DEFAULT_DEPRECATION_REASON, + item.span, + &format!("the lint `{}` has the default deprecation reason", item.ident.name), + ); + } + } + } + } else if let Some(macro_call) = root_macro_call_first_node(cx, item) { + if !matches!( + cx.tcx.item_name(macro_call.def_id).as_str(), + "impl_lint_pass" | "declare_lint_pass" + ) { + return; + } + if let hir::ItemKind::Impl(hir::Impl { + of_trait: None, + items: impl_item_refs, + .. + }) = item.kind + { + let mut collector = LintCollector { + output: &mut self.registered_lints, + cx, + }; + let body_id = cx.tcx.hir().body_owned_by( + impl_item_refs + .iter() + .find(|iiref| iiref.ident.as_str() == "get_lints") + .expect("LintPass needs to implement get_lints") + .id + .hir_id(), + ); + collector.visit_expr(&cx.tcx.hir().body(body_id).value); + } + } + } + + fn check_crate_post(&mut self, cx: &LateContext<'tcx>) { + if is_lint_allowed(cx, LINT_WITHOUT_LINT_PASS, CRATE_HIR_ID) { + return; + } + + for (lint_name, &lint_span) in &self.declared_lints { + // When using the `declare_tool_lint!` macro, the original `lint_span`'s + // file points to "<rustc macros>". + // `compiletest-rs` thinks that's an error in a different file and + // just ignores it. This causes the test in compile-fail/lint_pass + // not able to capture the error. + // Therefore, we need to climb the macro expansion tree and find the + // actual span that invoked `declare_tool_lint!`: + let lint_span = lint_span.ctxt().outer_expn_data().call_site; + + if !self.registered_lints.contains(lint_name) { + span_lint( + cx, + LINT_WITHOUT_LINT_PASS, + lint_span, + &format!("the lint `{}` is not added to any `LintPass`", lint_name), + ); + } + } + } +} + +fn is_lint_ref_type<'tcx>(cx: &LateContext<'tcx>, ty: &Ty<'_>) -> bool { + if let TyKind::Rptr( + _, + MutTy { + ty: inner, + mutbl: Mutability::Not, + }, + ) = ty.kind + { + if let TyKind::Path(ref path) = inner.kind { + if let Res::Def(DefKind::Struct, def_id) = cx.qpath_res(path, inner.hir_id) { + return match_def_path(cx, def_id, &paths::LINT); + } + } + } + + false +} + +fn check_invalid_clippy_version_attribute(cx: &LateContext<'_>, item: &'_ Item<'_>) { + if let Some(value) = extract_clippy_version_value(cx, item) { + // The `sym!` macro doesn't work as it only expects a single token. + // It's better to keep it this way and have a direct `Symbol::intern` call here. + if value == Symbol::intern("pre 1.29.0") { + return; + } + + if RustcVersion::parse(value.as_str()).is_err() { + span_lint_and_help( + cx, + INVALID_CLIPPY_VERSION_ATTRIBUTE, + item.span, + "this item has an invalid `clippy::version` attribute", + None, + "please use a valid sematic version, see `doc/adding_lints.md`", + ); + } + } else { + span_lint_and_help( + cx, + MISSING_CLIPPY_VERSION_ATTRIBUTE, + item.span, + "this lint is missing the `clippy::version` attribute or version value", + None, + "please use a `clippy::version` attribute, see `doc/adding_lints.md`", + ); + } +} + +/// This function extracts the version value of a `clippy::version` attribute if the given value has +/// one +fn extract_clippy_version_value(cx: &LateContext<'_>, item: &'_ Item<'_>) -> Option<Symbol> { + let attrs = cx.tcx.hir().attrs(item.hir_id()); + attrs.iter().find_map(|attr| { + if_chain! { + // Identify attribute + if let ast::AttrKind::Normal(ref attr_kind, _) = &attr.kind; + if let [tool_name, attr_name] = &attr_kind.path.segments[..]; + if tool_name.ident.name == sym::clippy; + if attr_name.ident.name == sym::version; + if let Some(version) = attr.value_str(); + then { + Some(version) + } else { + None + } + } + }) +} + +struct LintCollector<'a, 'tcx> { + output: &'a mut FxHashSet<Symbol>, + cx: &'a LateContext<'tcx>, +} + +impl<'a, 'tcx> Visitor<'tcx> for LintCollector<'a, 'tcx> { + type NestedFilter = nested_filter::All; + + fn visit_path(&mut self, path: &'tcx Path<'_>, _: HirId) { + if path.segments.len() == 1 { + self.output.insert(path.segments[0].ident.name); + } + } + + fn nested_visit_map(&mut self) -> Self::Map { + self.cx.tcx.hir() + } +} + +#[derive(Clone, Default)] +pub struct CompilerLintFunctions { + map: FxHashMap<&'static str, &'static str>, +} + +impl CompilerLintFunctions { + #[must_use] + pub fn new() -> Self { + let mut map = FxHashMap::default(); + map.insert("span_lint", "utils::span_lint"); + map.insert("struct_span_lint", "utils::span_lint"); + map.insert("lint", "utils::span_lint"); + map.insert("span_lint_note", "utils::span_lint_and_note"); + map.insert("span_lint_help", "utils::span_lint_and_help"); + Self { map } + } +} + +impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]); + +impl<'tcx> LateLintPass<'tcx> for CompilerLintFunctions { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { + if is_lint_allowed(cx, COMPILER_LINT_FUNCTIONS, expr.hir_id) { + return; + } + + if_chain! { + if let ExprKind::MethodCall(path, [self_arg, ..], _) = &expr.kind; + let fn_name = path.ident; + if let Some(sugg) = self.map.get(fn_name.as_str()); + let ty = cx.typeck_results().expr_ty(self_arg).peel_refs(); + if match_type(cx, ty, &paths::EARLY_CONTEXT) + || match_type(cx, ty, &paths::LATE_CONTEXT); + then { + span_lint_and_help( + cx, + COMPILER_LINT_FUNCTIONS, + path.ident.span, + "usage of a compiler lint function", + None, + &format!("please use the Clippy variant of this function: `{}`", sugg), + ); + } + } + } +} + +declare_lint_pass!(OuterExpnDataPass => [OUTER_EXPN_EXPN_DATA]); + +impl<'tcx> LateLintPass<'tcx> for OuterExpnDataPass { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) { + if is_lint_allowed(cx, OUTER_EXPN_EXPN_DATA, expr.hir_id) { + return; + } + + let (method_names, arg_lists, spans) = method_calls(expr, 2); + let method_names: Vec<&str> = method_names.iter().map(Symbol::as_str).collect(); + if_chain! { + if let ["expn_data", "outer_expn"] = method_names.as_slice(); + let args = arg_lists[1]; + if args.len() == 1; + let self_arg = &args[0]; + let self_ty = cx.typeck_results().expr_ty(self_arg).peel_refs(); + if match_type(cx, self_ty, &paths::SYNTAX_CONTEXT); + then { + span_lint_and_sugg( + cx, + OUTER_EXPN_EXPN_DATA, + spans[1].with_hi(expr.span.hi()), + "usage of `outer_expn().expn_data()`", + "try", + "outer_expn_data()".to_string(), + Applicability::MachineApplicable, + ); + } + } + } +} + +declare_lint_pass!(ProduceIce => [PRODUCE_ICE]); + +impl EarlyLintPass for ProduceIce { + fn check_fn(&mut self, _: &EarlyContext<'_>, fn_kind: FnKind<'_>, _: Span, _: NodeId) { + assert!(!is_trigger_fn(fn_kind), "Would you like some help with that?"); + } +} + +fn is_trigger_fn(fn_kind: FnKind<'_>) -> bool { + match fn_kind { + FnKind::Fn(_, ident, ..) => ident.name.as_str() == "it_looks_like_you_are_trying_to_kill_clippy", + FnKind::Closure(..) => false, + } +} + +declare_lint_pass!(CollapsibleCalls => [COLLAPSIBLE_SPAN_LINT_CALLS]); + +impl<'tcx> LateLintPass<'tcx> for CollapsibleCalls { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) { + if is_lint_allowed(cx, COLLAPSIBLE_SPAN_LINT_CALLS, expr.hir_id) { + return; + } + + if_chain! { + if let ExprKind::Call(func, and_then_args) = expr.kind; + if is_expr_path_def_path(cx, func, &["clippy_utils", "diagnostics", "span_lint_and_then"]); + if and_then_args.len() == 5; + if let ExprKind::Closure(&Closure { body, .. }) = &and_then_args[4].kind; + let body = cx.tcx.hir().body(body); + let only_expr = peel_blocks_with_stmt(&body.value); + if let ExprKind::MethodCall(ps, span_call_args, _) = &only_expr.kind; + if let ExprKind::Path(..) = span_call_args[0].kind; + then { + let and_then_snippets = get_and_then_snippets(cx, and_then_args); + let mut sle = SpanlessEq::new(cx).deny_side_effects(); + match ps.ident.as_str() { + "span_suggestion" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => { + suggest_suggestion(cx, expr, &and_then_snippets, &span_suggestion_snippets(cx, span_call_args)); + }, + "span_help" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => { + let help_snippet = snippet(cx, span_call_args[2].span, r#""...""#); + suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), true); + }, + "span_note" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => { + let note_snippet = snippet(cx, span_call_args[2].span, r#""...""#); + suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), true); + }, + "help" => { + let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#); + suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), false); + } + "note" => { + let note_snippet = snippet(cx, span_call_args[1].span, r#""...""#); + suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), false); + } + _ => (), + } + } + } + } +} + +struct AndThenSnippets<'a> { + cx: Cow<'a, str>, + lint: Cow<'a, str>, + span: Cow<'a, str>, + msg: Cow<'a, str>, +} + +fn get_and_then_snippets<'a, 'hir>(cx: &LateContext<'_>, and_then_snippets: &'hir [Expr<'hir>]) -> AndThenSnippets<'a> { + let cx_snippet = snippet(cx, and_then_snippets[0].span, "cx"); + let lint_snippet = snippet(cx, and_then_snippets[1].span, ".."); + let span_snippet = snippet(cx, and_then_snippets[2].span, "span"); + let msg_snippet = snippet(cx, and_then_snippets[3].span, r#""...""#); + + AndThenSnippets { + cx: cx_snippet, + lint: lint_snippet, + span: span_snippet, + msg: msg_snippet, + } +} + +struct SpanSuggestionSnippets<'a> { + help: Cow<'a, str>, + sugg: Cow<'a, str>, + applicability: Cow<'a, str>, +} + +fn span_suggestion_snippets<'a, 'hir>( + cx: &LateContext<'_>, + span_call_args: &'hir [Expr<'hir>], +) -> SpanSuggestionSnippets<'a> { + let help_snippet = snippet(cx, span_call_args[2].span, r#""...""#); + let sugg_snippet = snippet(cx, span_call_args[3].span, ".."); + let applicability_snippet = snippet(cx, span_call_args[4].span, "Applicability::MachineApplicable"); + + SpanSuggestionSnippets { + help: help_snippet, + sugg: sugg_snippet, + applicability: applicability_snippet, + } +} + +fn suggest_suggestion( + cx: &LateContext<'_>, + expr: &Expr<'_>, + and_then_snippets: &AndThenSnippets<'_>, + span_suggestion_snippets: &SpanSuggestionSnippets<'_>, +) { + span_lint_and_sugg( + cx, + COLLAPSIBLE_SPAN_LINT_CALLS, + expr.span, + "this call is collapsible", + "collapse into", + format!( + "span_lint_and_sugg({}, {}, {}, {}, {}, {}, {})", + and_then_snippets.cx, + and_then_snippets.lint, + and_then_snippets.span, + and_then_snippets.msg, + span_suggestion_snippets.help, + span_suggestion_snippets.sugg, + span_suggestion_snippets.applicability + ), + Applicability::MachineApplicable, + ); +} + +fn suggest_help( + cx: &LateContext<'_>, + expr: &Expr<'_>, + and_then_snippets: &AndThenSnippets<'_>, + help: &str, + with_span: bool, +) { + let option_span = if with_span { + format!("Some({})", and_then_snippets.span) + } else { + "None".to_string() + }; + + span_lint_and_sugg( + cx, + COLLAPSIBLE_SPAN_LINT_CALLS, + expr.span, + "this call is collapsible", + "collapse into", + format!( + "span_lint_and_help({}, {}, {}, {}, {}, {})", + and_then_snippets.cx, + and_then_snippets.lint, + and_then_snippets.span, + and_then_snippets.msg, + &option_span, + help + ), + Applicability::MachineApplicable, + ); +} + +fn suggest_note( + cx: &LateContext<'_>, + expr: &Expr<'_>, + and_then_snippets: &AndThenSnippets<'_>, + note: &str, + with_span: bool, +) { + let note_span = if with_span { + format!("Some({})", and_then_snippets.span) + } else { + "None".to_string() + }; + + span_lint_and_sugg( + cx, + COLLAPSIBLE_SPAN_LINT_CALLS, + expr.span, + "this call is collapsible", + "collapse into", + format!( + "span_lint_and_note({}, {}, {}, {}, {}, {})", + and_then_snippets.cx, + and_then_snippets.lint, + and_then_snippets.span, + and_then_snippets.msg, + note_span, + note + ), + Applicability::MachineApplicable, + ); +} + +declare_lint_pass!(MatchTypeOnDiagItem => [MATCH_TYPE_ON_DIAGNOSTIC_ITEM]); + +impl<'tcx> LateLintPass<'tcx> for MatchTypeOnDiagItem { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) { + if is_lint_allowed(cx, MATCH_TYPE_ON_DIAGNOSTIC_ITEM, expr.hir_id) { + return; + } + + if_chain! { + // Check if this is a call to utils::match_type() + if let ExprKind::Call(fn_path, [context, ty, ty_path]) = expr.kind; + if is_expr_path_def_path(cx, fn_path, &["clippy_utils", "ty", "match_type"]); + // Extract the path to the matched type + if let Some(segments) = path_to_matched_type(cx, ty_path); + let segments: Vec<&str> = segments.iter().map(Symbol::as_str).collect(); + if let Some(ty_did) = def_path_res(cx, &segments[..]).opt_def_id(); + // Check if the matched type is a diagnostic item + if let Some(item_name) = cx.tcx.get_diagnostic_name(ty_did); + then { + // TODO: check paths constants from external crates. + let cx_snippet = snippet(cx, context.span, "_"); + let ty_snippet = snippet(cx, ty.span, "_"); + + span_lint_and_sugg( + cx, + MATCH_TYPE_ON_DIAGNOSTIC_ITEM, + expr.span, + "usage of `clippy_utils::ty::match_type()` on a type diagnostic item", + "try", + format!("clippy_utils::ty::is_type_diagnostic_item({}, {}, sym::{})", cx_snippet, ty_snippet, item_name), + Applicability::MaybeIncorrect, + ); + } + } + } +} + +fn path_to_matched_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<Vec<Symbol>> { + use rustc_hir::ItemKind; + + match &expr.kind { + ExprKind::AddrOf(.., expr) => return path_to_matched_type(cx, expr), + ExprKind::Path(qpath) => match cx.qpath_res(qpath, expr.hir_id) { + Res::Local(hir_id) => { + let parent_id = cx.tcx.hir().get_parent_node(hir_id); + if let Some(Node::Local(local)) = cx.tcx.hir().find(parent_id) { + if let Some(init) = local.init { + return path_to_matched_type(cx, init); + } + } + }, + Res::Def(DefKind::Const | DefKind::Static(..), def_id) => { + if let Some(Node::Item(item)) = cx.tcx.hir().get_if_local(def_id) { + if let ItemKind::Const(.., body_id) | ItemKind::Static(.., body_id) = item.kind { + let body = cx.tcx.hir().body(body_id); + return path_to_matched_type(cx, &body.value); + } + } + }, + _ => {}, + }, + ExprKind::Array(exprs) => { + let segments: Vec<Symbol> = exprs + .iter() + .filter_map(|expr| { + if let ExprKind::Lit(lit) = &expr.kind { + if let LitKind::Str(sym, _) = lit.node { + return Some(sym); + } + } + + None + }) + .collect(); + + if segments.len() == exprs.len() { + return Some(segments); + } + }, + _ => {}, + } + + None +} + +// This is not a complete resolver for paths. It works on all the paths currently used in the paths +// module. That's all it does and all it needs to do. +pub fn check_path(cx: &LateContext<'_>, path: &[&str]) -> bool { + if def_path_res(cx, path) != Res::Err { + return true; + } + + // Some implementations can't be found by `path_to_res`, particularly inherent + // implementations of native types. Check lang items. + let path_syms: Vec<_> = path.iter().map(|p| Symbol::intern(p)).collect(); + let lang_items = cx.tcx.lang_items(); + // This list isn't complete, but good enough for our current list of paths. + let incoherent_impls = [ + SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F32), + SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F64), + SimplifiedTypeGen::SliceSimplifiedType, + SimplifiedTypeGen::StrSimplifiedType, + ] + .iter() + .flat_map(|&ty| cx.tcx.incoherent_impls(ty)); + for item_def_id in lang_items.items().iter().flatten().chain(incoherent_impls) { + let lang_item_path = cx.get_def_path(*item_def_id); + if path_syms.starts_with(&lang_item_path) { + if let [item] = &path_syms[lang_item_path.len()..] { + if matches!( + cx.tcx.def_kind(*item_def_id), + DefKind::Mod | DefKind::Enum | DefKind::Trait + ) { + for child in cx.tcx.module_children(*item_def_id) { + if child.ident.name == *item { + return true; + } + } + } else { + for child in cx.tcx.associated_item_def_ids(*item_def_id) { + if cx.tcx.item_name(*child) == *item { + return true; + } + } + } + } + } + } + + false +} + +declare_lint_pass!(InvalidPaths => [INVALID_PATHS]); + +impl<'tcx> LateLintPass<'tcx> for InvalidPaths { + fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) { + let local_def_id = &cx.tcx.parent_module(item.hir_id()); + let mod_name = &cx.tcx.item_name(local_def_id.to_def_id()); + if_chain! { + if mod_name.as_str() == "paths"; + if let hir::ItemKind::Const(ty, body_id) = item.kind; + let ty = hir_ty_to_ty(cx.tcx, ty); + if let ty::Array(el_ty, _) = &ty.kind(); + if let ty::Ref(_, el_ty, _) = &el_ty.kind(); + if el_ty.is_str(); + let body = cx.tcx.hir().body(body_id); + let typeck_results = cx.tcx.typeck_body(body_id); + if let Some(Constant::Vec(path)) = constant_simple(cx, typeck_results, &body.value); + let path: Vec<&str> = path.iter().map(|x| { + if let Constant::Str(s) = x { + s.as_str() + } else { + // We checked the type of the constant above + unreachable!() + } + }).collect(); + if !check_path(cx, &path[..]); + then { + span_lint(cx, INVALID_PATHS, item.span, "invalid path"); + } + } + } +} + +#[derive(Default)] +pub struct InterningDefinedSymbol { + // Maps the symbol value to the constant DefId. + symbol_map: FxHashMap<u32, DefId>, +} + +impl_lint_pass!(InterningDefinedSymbol => [INTERNING_DEFINED_SYMBOL, UNNECESSARY_SYMBOL_STR]); + +impl<'tcx> LateLintPass<'tcx> for InterningDefinedSymbol { + fn check_crate(&mut self, cx: &LateContext<'_>) { + if !self.symbol_map.is_empty() { + return; + } + + for &module in &[&paths::KW_MODULE, &paths::SYM_MODULE] { + if let Some(def_id) = def_path_res(cx, module).opt_def_id() { + for item in cx.tcx.module_children(def_id).iter() { + if_chain! { + if let Res::Def(DefKind::Const, item_def_id) = item.res; + let ty = cx.tcx.type_of(item_def_id); + if match_type(cx, ty, &paths::SYMBOL); + if let Ok(ConstValue::Scalar(value)) = cx.tcx.const_eval_poly(item_def_id); + if let Ok(value) = value.to_u32(); + then { + self.symbol_map.insert(value, item_def_id); + } + } + } + } + } + } + + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { + if_chain! { + if let ExprKind::Call(func, [arg]) = &expr.kind; + if let ty::FnDef(def_id, _) = cx.typeck_results().expr_ty(func).kind(); + if match_def_path(cx, *def_id, &paths::SYMBOL_INTERN); + if let Some(Constant::Str(arg)) = constant_simple(cx, cx.typeck_results(), arg); + let value = Symbol::intern(&arg).as_u32(); + if let Some(&def_id) = self.symbol_map.get(&value); + then { + span_lint_and_sugg( + cx, + INTERNING_DEFINED_SYMBOL, + is_expn_of(expr.span, "sym").unwrap_or(expr.span), + "interning a defined symbol", + "try", + cx.tcx.def_path_str(def_id), + Applicability::MachineApplicable, + ); + } + } + if let ExprKind::Binary(op, left, right) = expr.kind { + if matches!(op.node, BinOpKind::Eq | BinOpKind::Ne) { + let data = [ + (left, self.symbol_str_expr(left, cx)), + (right, self.symbol_str_expr(right, cx)), + ]; + match data { + // both operands are a symbol string + [(_, Some(left)), (_, Some(right))] => { + span_lint_and_sugg( + cx, + UNNECESSARY_SYMBOL_STR, + expr.span, + "unnecessary `Symbol` to string conversion", + "try", + format!( + "{} {} {}", + left.as_symbol_snippet(cx), + op.node.as_str(), + right.as_symbol_snippet(cx), + ), + Applicability::MachineApplicable, + ); + }, + // one of the operands is a symbol string + [(expr, Some(symbol)), _] | [_, (expr, Some(symbol))] => { + // creating an owned string for comparison + if matches!(symbol, SymbolStrExpr::Expr { is_to_owned: true, .. }) { + span_lint_and_sugg( + cx, + UNNECESSARY_SYMBOL_STR, + expr.span, + "unnecessary string allocation", + "try", + format!("{}.as_str()", symbol.as_symbol_snippet(cx)), + Applicability::MachineApplicable, + ); + } + }, + // nothing found + [(_, None), (_, None)] => {}, + } + } + } + } +} + +impl InterningDefinedSymbol { + fn symbol_str_expr<'tcx>(&self, expr: &'tcx Expr<'tcx>, cx: &LateContext<'tcx>) -> Option<SymbolStrExpr<'tcx>> { + static IDENT_STR_PATHS: &[&[&str]] = &[&paths::IDENT_AS_STR, &paths::TO_STRING_METHOD]; + static SYMBOL_STR_PATHS: &[&[&str]] = &[ + &paths::SYMBOL_AS_STR, + &paths::SYMBOL_TO_IDENT_STRING, + &paths::TO_STRING_METHOD, + ]; + let call = if_chain! { + if let ExprKind::AddrOf(_, _, e) = expr.kind; + if let ExprKind::Unary(UnOp::Deref, e) = e.kind; + then { e } else { expr } + }; + if_chain! { + // is a method call + if let ExprKind::MethodCall(_, [item], _) = call.kind; + if let Some(did) = cx.typeck_results().type_dependent_def_id(call.hir_id); + let ty = cx.typeck_results().expr_ty(item); + // ...on either an Ident or a Symbol + if let Some(is_ident) = if match_type(cx, ty, &paths::SYMBOL) { + Some(false) + } else if match_type(cx, ty, &paths::IDENT) { + Some(true) + } else { + None + }; + // ...which converts it to a string + let paths = if is_ident { IDENT_STR_PATHS } else { SYMBOL_STR_PATHS }; + if let Some(path) = paths.iter().find(|path| match_def_path(cx, did, path)); + then { + let is_to_owned = path.last().unwrap().ends_with("string"); + return Some(SymbolStrExpr::Expr { + item, + is_ident, + is_to_owned, + }); + } + } + // is a string constant + if let Some(Constant::Str(s)) = constant_simple(cx, cx.typeck_results(), expr) { + let value = Symbol::intern(&s).as_u32(); + // ...which matches a symbol constant + if let Some(&def_id) = self.symbol_map.get(&value) { + return Some(SymbolStrExpr::Const(def_id)); + } + } + None + } +} + +enum SymbolStrExpr<'tcx> { + /// a string constant with a corresponding symbol constant + Const(DefId), + /// a "symbol to string" expression like `symbol.as_str()` + Expr { + /// part that evaluates to `Symbol` or `Ident` + item: &'tcx Expr<'tcx>, + is_ident: bool, + /// whether an owned `String` is created like `to_ident_string()` + is_to_owned: bool, + }, +} + +impl<'tcx> SymbolStrExpr<'tcx> { + /// Returns a snippet that evaluates to a `Symbol` and is const if possible + fn as_symbol_snippet(&self, cx: &LateContext<'_>) -> Cow<'tcx, str> { + match *self { + Self::Const(def_id) => cx.tcx.def_path_str(def_id).into(), + Self::Expr { item, is_ident, .. } => { + let mut snip = snippet(cx, item.span.source_callsite(), ".."); + if is_ident { + // get `Ident.name` + snip.to_mut().push_str(".name"); + } + snip + }, + } + } +} + +declare_lint_pass!(IfChainStyle => [IF_CHAIN_STYLE]); + +impl<'tcx> LateLintPass<'tcx> for IfChainStyle { + fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'_>) { + let (local, after, if_chain_span) = if_chain! { + if let [Stmt { kind: StmtKind::Local(local), .. }, after @ ..] = block.stmts; + if let Some(if_chain_span) = is_expn_of(block.span, "if_chain"); + then { (local, after, if_chain_span) } else { return } + }; + if is_first_if_chain_expr(cx, block.hir_id, if_chain_span) { + span_lint( + cx, + IF_CHAIN_STYLE, + if_chain_local_span(cx, local, if_chain_span), + "`let` expression should be above the `if_chain!`", + ); + } else if local.span.ctxt() == block.span.ctxt() && is_if_chain_then(after, block.expr, if_chain_span) { + span_lint( + cx, + IF_CHAIN_STYLE, + if_chain_local_span(cx, local, if_chain_span), + "`let` expression should be inside `then { .. }`", + ); + } + } + + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) { + let (cond, then, els) = if let Some(higher::IfOrIfLet { cond, r#else, then }) = higher::IfOrIfLet::hir(expr) { + (cond, then, r#else.is_some()) + } else { + return; + }; + let then_block = match then.kind { + ExprKind::Block(block, _) => block, + _ => return, + }; + let if_chain_span = is_expn_of(expr.span, "if_chain"); + if !els { + check_nested_if_chains(cx, expr, then_block, if_chain_span); + } + let if_chain_span = match if_chain_span { + None => return, + Some(span) => span, + }; + // check for `if a && b;` + if_chain! { + if let ExprKind::Binary(op, _, _) = cond.kind; + if op.node == BinOpKind::And; + if cx.sess().source_map().is_multiline(cond.span); + then { + span_lint(cx, IF_CHAIN_STYLE, cond.span, "`if a && b;` should be `if a; if b;`"); + } + } + if is_first_if_chain_expr(cx, expr.hir_id, if_chain_span) + && is_if_chain_then(then_block.stmts, then_block.expr, if_chain_span) + { + span_lint(cx, IF_CHAIN_STYLE, expr.span, "`if_chain!` only has one `if`"); + } + } +} + +fn check_nested_if_chains( + cx: &LateContext<'_>, + if_expr: &Expr<'_>, + then_block: &Block<'_>, + if_chain_span: Option<Span>, +) { + #[rustfmt::skip] + let (head, tail) = match *then_block { + Block { stmts, expr: Some(tail), .. } => (stmts, tail), + Block { + stmts: &[ + ref head @ .., + Stmt { kind: StmtKind::Expr(tail) | StmtKind::Semi(tail), .. } + ], + .. + } => (head, tail), + _ => return, + }; + if_chain! { + if let Some(higher::IfOrIfLet { r#else: None, .. }) = higher::IfOrIfLet::hir(tail); + let sm = cx.sess().source_map(); + if head + .iter() + .all(|stmt| matches!(stmt.kind, StmtKind::Local(..)) && !sm.is_multiline(stmt.span)); + if if_chain_span.is_some() || !is_else_clause(cx.tcx, if_expr); + then {} else { return } + } + let (span, msg) = match (if_chain_span, is_expn_of(tail.span, "if_chain")) { + (None, Some(_)) => (if_expr.span, "this `if` can be part of the inner `if_chain!`"), + (Some(_), None) => (tail.span, "this `if` can be part of the outer `if_chain!`"), + (Some(a), Some(b)) if a != b => (b, "this `if_chain!` can be merged with the outer `if_chain!`"), + _ => return, + }; + span_lint_and_then(cx, IF_CHAIN_STYLE, span, msg, |diag| { + let (span, msg) = match head { + [] => return, + [stmt] => (stmt.span, "this `let` statement can also be in the `if_chain!`"), + [a, .., b] => ( + a.span.to(b.span), + "these `let` statements can also be in the `if_chain!`", + ), + }; + diag.span_help(span, msg); + }); +} + +fn is_first_if_chain_expr(cx: &LateContext<'_>, hir_id: HirId, if_chain_span: Span) -> bool { + cx.tcx + .hir() + .parent_iter(hir_id) + .find(|(_, node)| { + #[rustfmt::skip] + !matches!(node, Node::Expr(Expr { kind: ExprKind::Block(..), .. }) | Node::Stmt(_)) + }) + .map_or(false, |(id, _)| { + is_expn_of(cx.tcx.hir().span(id), "if_chain") != Some(if_chain_span) + }) +} + +/// Checks a trailing slice of statements and expression of a `Block` to see if they are part +/// of the `then {..}` portion of an `if_chain!` +fn is_if_chain_then(stmts: &[Stmt<'_>], expr: Option<&Expr<'_>>, if_chain_span: Span) -> bool { + let span = if let [stmt, ..] = stmts { + stmt.span + } else if let Some(expr) = expr { + expr.span + } else { + // empty `then {}` + return true; + }; + is_expn_of(span, "if_chain").map_or(true, |span| span != if_chain_span) +} + +/// Creates a `Span` for `let x = ..;` in an `if_chain!` call. +fn if_chain_local_span(cx: &LateContext<'_>, local: &Local<'_>, if_chain_span: Span) -> Span { + let mut span = local.pat.span; + if let Some(init) = local.init { + span = span.to(init.span); + } + span.adjust(if_chain_span.ctxt().outer_expn()); + let sm = cx.sess().source_map(); + let span = sm.span_extend_to_prev_str(span, "let", false, true).unwrap_or(span); + let span = sm.span_extend_to_next_char(span, ';', false); + Span::new( + span.lo() - BytePos(3), + span.hi() + BytePos(1), + span.ctxt(), + span.parent(), + ) +} + +declare_lint_pass!(MsrvAttrImpl => [MISSING_MSRV_ATTR_IMPL]); + +impl LateLintPass<'_> for MsrvAttrImpl { + fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) { + if_chain! { + if let hir::ItemKind::Impl(hir::Impl { + of_trait: Some(lint_pass_trait_ref), + self_ty, + items, + .. + }) = &item.kind; + if let Some(lint_pass_trait_def_id) = lint_pass_trait_ref.trait_def_id(); + let is_late_pass = match_def_path(cx, lint_pass_trait_def_id, &paths::LATE_LINT_PASS); + if is_late_pass || match_def_path(cx, lint_pass_trait_def_id, &paths::EARLY_LINT_PASS); + let self_ty = hir_ty_to_ty(cx.tcx, self_ty); + if let ty::Adt(self_ty_def, _) = self_ty.kind(); + if self_ty_def.is_struct(); + if self_ty_def.all_fields().any(|f| { + cx.tcx + .type_of(f.did) + .walk() + .filter(|t| matches!(t.unpack(), GenericArgKind::Type(_))) + .any(|t| match_type(cx, t.expect_ty(), &paths::RUSTC_VERSION)) + }); + if !items.iter().any(|item| item.ident.name == sym!(enter_lint_attrs)); + then { + let context = if is_late_pass { "LateContext" } else { "EarlyContext" }; + let lint_pass = if is_late_pass { "LateLintPass" } else { "EarlyLintPass" }; + let span = cx.sess().source_map().span_through_char(item.span, '{'); + span_lint_and_sugg( + cx, + MISSING_MSRV_ATTR_IMPL, + span, + &format!("`extract_msrv_attr!` macro missing from `{lint_pass}` implementation"), + &format!("add `extract_msrv_attr!({context})` to the `{lint_pass}` implementation"), + format!("{}\n extract_msrv_attr!({context});", snippet(cx, span, "..")), + Applicability::MachineApplicable, + ); + } + } + } +} |