1 use crate::utils::{match_type, match_def_path, paths, span_help_and_lint, span_lint, walk_ptrs_ty};
3 use if_chain::if_chain;
5 use rustc::hir::def::{DefKind, Res};
6 use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
8 use rustc::lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintArray, LintPass};
9 use rustc::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
10 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
11 use syntax::ast::{Crate as AstCrate, ItemKind, Name};
12 use syntax::source_map::Span;
13 use syntax::symbol::LocalInternedString;
15 declare_clippy_lint! {
16 /// **What it does:** Checks for various things we like to keep tidy in clippy.
18 /// **Why is this bad?** We like to pretend we're an example of tidy code.
20 /// **Known problems:** None.
22 /// **Example:** Wrong ordering of the util::paths constants.
23 pub CLIPPY_LINTS_INTERNAL,
25 "various things that will negatively affect your clippy experience"
28 declare_clippy_lint! {
29 /// **What it does:** Ensures every lint is associated to a `LintPass`.
31 /// **Why is this bad?** The compiler only knows lints via a `LintPass`. Without
32 /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not
33 /// know the name of the lint.
35 /// **Known problems:** Only checks for lints associated using the
36 /// `declare_lint_pass!`, `impl_lint_pass!`, and `lint_array!` macros.
40 /// declare_lint! { pub LINT_1, ... }
41 /// declare_lint! { pub LINT_2, ... }
42 /// declare_lint! { pub FORGOTTEN_LINT, ... }
44 /// declare_lint_pass!(Pass => [LINT_1, LINT_2]);
45 /// // missing FORGOTTEN_LINT
47 pub LINT_WITHOUT_LINT_PASS,
49 "declaring a lint without associating it in a LintPass"
52 declare_clippy_lint! {
53 /// **What it does:** Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
54 /// variant of the function.
56 /// **Why is this bad?** The `utils::*` variants also add a link to the Clippy documentation to the
57 /// warning/error messages.
59 /// **Known problems:** None.
64 /// cx.span_lint(LINT_NAME, "message");
69 /// utils::span_lint(cx, LINT_NAME, "message");
71 pub COMPILER_LINT_FUNCTIONS,
73 "usage of the lint functions of the compiler instead of the utils::* variant"
76 declare_lint_pass!(ClippyLintsInternal => [CLIPPY_LINTS_INTERNAL]);
78 impl EarlyLintPass for ClippyLintsInternal {
79 fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &AstCrate) {
80 if let Some(utils) = krate.module.items.iter().find(|item| item.ident.name == *sym::utils) {
81 if let ItemKind::Mod(ref utils_mod) = utils.node {
82 if let Some(paths) = utils_mod.items.iter().find(|item| item.ident.name == *sym::paths) {
83 if let ItemKind::Mod(ref paths_mod) = paths.node {
84 let mut last_name: Option<LocalInternedString> = None;
85 for item in &*paths_mod.items {
86 let name = item.ident.as_str();
87 if let Some(ref last_name) = last_name {
88 if **last_name > *name {
91 CLIPPY_LINTS_INTERNAL,
93 "this constant should be before the previous constant due to lexical \
98 last_name = Some(name);
107 #[derive(Clone, Debug, Default)]
108 pub struct LintWithoutLintPass {
109 declared_lints: FxHashMap<Name, Span>,
110 registered_lints: FxHashSet<Name>,
113 impl_lint_pass!(LintWithoutLintPass => [LINT_WITHOUT_LINT_PASS]);
115 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for LintWithoutLintPass {
116 fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
117 if let hir::ItemKind::Static(ref ty, MutImmutable, _) = item.node {
118 if is_lint_ref_type(cx, ty) {
119 self.declared_lints.insert(item.ident.name, item.span);
121 } else if let hir::ItemKind::Impl(.., Some(ref trait_ref), _, ref impl_item_refs) = item.node {
123 if let hir::TraitRef{path, ..} = trait_ref;
124 if let Res::Def(DefKind::Trait, def_id) = path.res;
125 if match_def_path(cx, def_id, &*paths::LINT_PASS);
127 let mut collector = LintCollector {
128 output: &mut self.registered_lints,
131 let body_id = cx.tcx.hir().body_owned_by(
134 .find(|iiref| iiref.ident.as_str() == "get_lints")
135 .expect("LintPass needs to implement get_lints")
138 collector.visit_expr(&cx.tcx.hir().body(body_id).value);
144 fn check_crate_post(&mut self, cx: &LateContext<'a, 'tcx>, _: &'tcx Crate) {
145 for (lint_name, &lint_span) in &self.declared_lints {
146 // When using the `declare_tool_lint!` macro, the original `lint_span`'s
147 // file points to "<rustc macros>".
148 // `compiletest-rs` thinks that's an error in a different file and
149 // just ignores it. This causes the test in compile-fail/lint_pass
150 // not able to capture the error.
151 // Therefore, we need to climb the macro expansion tree and find the
152 // actual span that invoked `declare_tool_lint!`:
153 let lint_span = lint_span
157 .map(|ei| ei.call_site)
158 .expect("unable to get call_site");
160 if !self.registered_lints.contains(lint_name) {
163 LINT_WITHOUT_LINT_PASS,
165 &format!("the lint `{}` is not added to any `LintPass`", lint_name),
172 fn is_lint_ref_type<'tcx>(cx: &LateContext<'_, 'tcx>, ty: &Ty) -> bool {
181 if let TyKind::Path(ref path) = inner.node {
182 if let Res::Def(DefKind::Struct, def_id) = cx.tables.qpath_res(path, inner.hir_id) {
183 return match_def_path(cx, def_id, &*paths::LINT);
191 struct LintCollector<'a, 'tcx: 'a> {
192 output: &'a mut FxHashSet<Name>,
193 cx: &'a LateContext<'a, 'tcx>,
196 impl<'a, 'tcx: 'a> Visitor<'tcx> for LintCollector<'a, 'tcx> {
197 fn visit_expr(&mut self, expr: &'tcx Expr) {
198 walk_expr(self, expr);
201 fn visit_path(&mut self, path: &'tcx Path, _: HirId) {
202 if path.segments.len() == 1 {
203 self.output.insert(path.segments[0].ident.name);
206 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
207 NestedVisitorMap::All(&self.cx.tcx.hir())
211 #[derive(Clone, Default)]
212 pub struct CompilerLintFunctions {
213 map: FxHashMap<String, String>,
216 impl CompilerLintFunctions {
217 pub fn new() -> Self {
218 let mut map = FxHashMap::default();
219 map.insert("span_lint".to_string(), "utils::span_lint".to_string());
220 map.insert("struct_span_lint".to_string(), "utils::span_lint".to_string());
221 map.insert("lint".to_string(), "utils::span_lint".to_string());
222 map.insert("span_lint_note".to_string(), "utils::span_note_and_lint".to_string());
223 map.insert("span_lint_help".to_string(), "utils::span_help_and_lint".to_string());
228 impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]);
230 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CompilerLintFunctions {
231 fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
233 if let ExprKind::MethodCall(ref path, _, ref args) = expr.node;
234 let fn_name = path.ident.as_str().to_string();
235 if let Some(sugg) = self.map.get(&fn_name);
236 let ty = walk_ptrs_ty(cx.tables.expr_ty(&args[0]));
237 if match_type(cx, ty, &*paths::EARLY_CONTEXT)
238 || match_type(cx, ty, &*paths::LATE_CONTEXT);
242 COMPILER_LINT_FUNCTIONS,
244 "usage of a compiler lint function",
245 &format!("please use the Clippy variant of this function: `{}`", sugg),