1 use crate::utils::{match_type, paths, span_help_and_lint, span_lint, walk_ptrs_ty};
2 use if_chain::if_chain;
4 use rustc::hir::def::Def;
5 use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
7 use rustc::lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintArray, LintPass};
8 use rustc::{declare_tool_lint, lint_array};
9 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
10 use syntax::ast::{Crate as AstCrate, ItemKind, Name};
11 use syntax::source_map::Span;
12 use syntax::symbol::LocalInternedString;
14 declare_clippy_lint! {
15 /// **What it does:** Checks for various things we like to keep tidy in clippy.
17 /// **Why is this bad?** We like to pretend we're an example of tidy code.
19 /// **Known problems:** None.
21 /// **Example:** Wrong ordering of the util::paths constants.
22 pub CLIPPY_LINTS_INTERNAL,
24 "various things that will negatively affect your clippy experience"
27 declare_clippy_lint! {
28 /// **What it does:** Ensures every lint is associated to a `LintPass`.
30 /// **Why is this bad?** The compiler only knows lints via a `LintPass`. Without
31 /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not
32 /// know the name of the lint.
34 /// **Known problems:** Only checks for lints associated using the `lint_array!`
39 /// declare_lint! { pub LINT_1, ... }
40 /// declare_lint! { pub LINT_2, ... }
41 /// declare_lint! { pub FORGOTTEN_LINT, ... }
44 /// impl LintPass for Pass {
45 /// fn get_lints(&self) -> LintArray {
46 /// lint_array![LINT_1, LINT_2]
47 /// // missing FORGOTTEN_LINT
51 pub LINT_WITHOUT_LINT_PASS,
53 "declaring a lint without associating it in a LintPass"
56 declare_clippy_lint! {
57 /// **What it does:** Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
58 /// variant of the function.
60 /// **Why is this bad?** The `utils::*` variants also add a link to the Clippy documentation to the
61 /// warning/error messages.
63 /// **Known problems:** None.
68 /// cx.span_lint(LINT_NAME, "message");
73 /// utils::span_lint(cx, LINT_NAME, "message");
75 pub COMPILER_LINT_FUNCTIONS,
77 "usage of the lint functions of the compiler instead of the utils::* variant"
80 #[derive(Copy, Clone)]
83 impl LintPass for Clippy {
84 fn get_lints(&self) -> LintArray {
85 lint_array!(CLIPPY_LINTS_INTERNAL)
88 fn name(&self) -> &'static str {
93 impl EarlyLintPass for Clippy {
94 fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &AstCrate) {
95 if let Some(utils) = krate.module.items.iter().find(|item| item.ident.name == "utils") {
96 if let ItemKind::Mod(ref utils_mod) = utils.node {
97 if let Some(paths) = utils_mod.items.iter().find(|item| item.ident.name == "paths") {
98 if let ItemKind::Mod(ref paths_mod) = paths.node {
99 let mut last_name: Option<LocalInternedString> = None;
100 for item in &paths_mod.items {
101 let name = item.ident.as_str();
102 if let Some(ref last_name) = last_name {
103 if **last_name > *name {
106 CLIPPY_LINTS_INTERNAL,
108 "this constant should be before the previous constant due to lexical \
113 last_name = Some(name);
122 #[derive(Clone, Debug, Default)]
123 pub struct LintWithoutLintPass {
124 declared_lints: FxHashMap<Name, Span>,
125 registered_lints: FxHashSet<Name>,
128 impl LintPass for LintWithoutLintPass {
129 fn get_lints(&self) -> LintArray {
130 lint_array!(LINT_WITHOUT_LINT_PASS)
132 fn name(&self) -> &'static str {
133 "LintWithoutLintPass"
137 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for LintWithoutLintPass {
138 fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
139 if let hir::ItemKind::Static(ref ty, MutImmutable, _) = item.node {
140 if is_lint_ref_type(cx, ty) {
141 self.declared_lints.insert(item.ident.name, item.span);
143 } else if let hir::ItemKind::Impl(.., Some(ref trait_ref), _, ref impl_item_refs) = item.node {
145 if let hir::TraitRef{path, ..} = trait_ref;
146 if let Def::Trait(def_id) = path.def;
147 if cx.match_def_path(def_id, &paths::LINT_PASS);
149 let mut collector = LintCollector {
150 output: &mut self.registered_lints,
153 let body_id = cx.tcx.hir().body_owned_by(impl_item_refs[0].id.hir_id);
154 collector.visit_expr(&cx.tcx.hir().body(body_id).value);
160 fn check_crate_post(&mut self, cx: &LateContext<'a, 'tcx>, _: &'tcx Crate) {
161 for (lint_name, &lint_span) in &self.declared_lints {
162 // When using the `declare_tool_lint!` macro, the original `lint_span`'s
163 // file points to "<rustc macros>".
164 // `compiletest-rs` thinks that's an error in a different file and
165 // just ignores it. This causes the test in compile-fail/lint_pass
166 // not able to capture the error.
167 // Therefore, we need to climb the macro expansion tree and find the
168 // actual span that invoked `declare_tool_lint!`:
169 let lint_span = lint_span
173 .map(|ei| ei.call_site)
174 .expect("unable to get call_site");
176 if !self.registered_lints.contains(lint_name) {
179 LINT_WITHOUT_LINT_PASS,
181 &format!("the lint `{}` is not added to any `LintPass`", lint_name),
188 fn is_lint_ref_type<'tcx>(cx: &LateContext<'_, 'tcx>, ty: &Ty) -> bool {
197 if let TyKind::Path(ref path) = inner.node {
198 if let Def::Struct(def_id) = cx.tables.qpath_def(path, inner.hir_id) {
199 return cx.match_def_path(def_id, &paths::LINT);
207 struct LintCollector<'a, 'tcx: 'a> {
208 output: &'a mut FxHashSet<Name>,
209 cx: &'a LateContext<'a, 'tcx>,
212 impl<'a, 'tcx: 'a> Visitor<'tcx> for LintCollector<'a, 'tcx> {
213 fn visit_expr(&mut self, expr: &'tcx Expr) {
214 walk_expr(self, expr);
217 fn visit_path(&mut self, path: &'tcx Path, _: HirId) {
218 if path.segments.len() == 1 {
219 self.output.insert(path.segments[0].ident.name);
222 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
223 NestedVisitorMap::All(&self.cx.tcx.hir())
227 #[derive(Clone, Default)]
228 pub struct CompilerLintFunctions {
229 map: FxHashMap<String, String>,
232 impl CompilerLintFunctions {
233 pub fn new() -> Self {
234 let mut map = FxHashMap::default();
235 map.insert("span_lint".to_string(), "utils::span_lint".to_string());
236 map.insert("struct_span_lint".to_string(), "utils::span_lint".to_string());
237 map.insert("lint".to_string(), "utils::span_lint".to_string());
238 map.insert("span_lint_note".to_string(), "utils::span_note_and_lint".to_string());
239 map.insert("span_lint_help".to_string(), "utils::span_help_and_lint".to_string());
244 impl LintPass for CompilerLintFunctions {
245 fn get_lints(&self) -> LintArray {
246 lint_array!(COMPILER_LINT_FUNCTIONS)
249 fn name(&self) -> &'static str {
250 "CompileLintFunctions"
254 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CompilerLintFunctions {
255 fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
257 if let ExprKind::MethodCall(ref path, _, ref args) = expr.node;
258 let fn_name = path.ident.as_str().to_string();
259 if let Some(sugg) = self.map.get(&fn_name);
260 let ty = walk_ptrs_ty(cx.tables.expr_ty(&args[0]));
261 if match_type(cx, ty, &paths::EARLY_CONTEXT)
262 || match_type(cx, ty, &paths::LATE_CONTEXT);
266 COMPILER_LINT_FUNCTIONS,
268 "usage of a compiler lint function",
269 &format!("please use the Clippy variant of this function: `{}`", sugg),