1 use clippy_utils::diagnostics::span_lint_and_sugg;
2 use itertools::Itertools;
3 use rustc_errors::Applicability;
4 use rustc_hir::{Item, ItemKind};
5 use rustc_lint::{LateContext, LateLintPass, LintContext};
6 use rustc_middle::lint::in_external_macro;
7 use rustc_session::{declare_tool_lint, impl_lint_pass};
8 use rustc_span::symbol::Ident;
10 declare_clippy_lint! {
11 /// **What it does:** Checks for fully capitalized names and optionally names containing a capitalized acronym.
13 /// **Why is this bad?** In CamelCase, acronyms count as one word.
14 /// See [naming conventions](https://rust-lang.github.io/api-guidelines/naming.html#casing-conforms-to-rfc-430-c-case)
17 /// By default, the lint only triggers on fully-capitalized names.
18 /// You can use the `upper-case-acronyms-aggressive: true` config option to enable linting
19 /// on all camel case names
21 /// **Known problems:** When two acronyms are contiguous, the lint can't tell where
22 /// the first acronym ends and the second starts, so it suggests to lowercase all of
23 /// the letters in the second acronym.
28 /// struct HTTPResponse;
32 /// struct HttpResponse;
34 pub UPPER_CASE_ACRONYMS,
36 "capitalized acronyms are against the naming convention"
40 pub struct UpperCaseAcronyms {
41 avoid_breaking_exported_api: bool,
42 upper_case_acronyms_aggressive: bool,
45 impl UpperCaseAcronyms {
46 pub fn new(avoid_breaking_exported_api: bool, aggressive: bool) -> Self {
48 avoid_breaking_exported_api,
49 upper_case_acronyms_aggressive: aggressive,
54 impl_lint_pass!(UpperCaseAcronyms => [UPPER_CASE_ACRONYMS]);
56 fn correct_ident(ident: &str) -> String {
57 let ident = ident.chars().rev().collect::<String>();
59 .split_inclusive(|x: char| !x.is_ascii_lowercase())
61 .map(|x| x.chars().rev().collect::<String>());
63 let mut ident = fragments.clone().next().unwrap();
64 for (ref prev, ref curr) in fragments.tuple_windows() {
67 .all(|s| s.len() == 1 && s.chars().next().unwrap().is_ascii_uppercase())
69 ident.push_str(&curr.to_ascii_lowercase());
77 fn check_ident(cx: &LateContext<'_>, ident: &Ident, be_aggressive: bool) {
78 let span = ident.span;
79 let ident = &ident.as_str();
80 let corrected = correct_ident(ident);
81 // warn if we have pure-uppercase idents
82 // assume that two-letter words are some kind of valid abbreviation like FP for false positive
84 if (ident.chars().all(|c| c.is_ascii_uppercase()) && ident.len() > 2)
85 // otherwise, warn if we have SOmeTHING lIKE THIs but only warn with the aggressive
86 // upper-case-acronyms-aggressive config option enabled
87 || (be_aggressive && ident != &corrected)
93 &format!("name `{}` contains a capitalized acronym", ident),
94 "consider making the acronym lowercase, except the initial letter",
96 Applicability::MaybeIncorrect,
101 impl LateLintPass<'_> for UpperCaseAcronyms {
102 fn check_item(&mut self, cx: &LateContext<'_>, it: &Item<'_>) {
103 // do not lint public items or in macros
104 if in_external_macro(cx.sess(), it.span)
105 || (self.avoid_breaking_exported_api && cx.access_levels.is_exported(it.hir_id()))
110 ItemKind::TyAlias(..) | ItemKind::Struct(..) | ItemKind::Trait(..) => {
111 check_ident(cx, &it.ident, self.upper_case_acronyms_aggressive);
113 ItemKind::Enum(ref enumdef, _) => {
114 // check enum variants seperately because again we only want to lint on private enums and
115 // the fn check_variant does not know about the vis of the enum of its variants
119 .for_each(|variant| check_ident(cx, &variant.ident, self.upper_case_acronyms_aggressive));