diff --git a/clippy_lints/src/enum_variants.rs b/clippy_lints/src/enum_variants.rs index 72553bd5d45..ec318a37952 100644 --- a/clippy_lints/src/enum_variants.rs +++ b/clippy_lints/src/enum_variants.rs @@ -3,7 +3,7 @@ use rustc::lint::*; use syntax::ast::*; use syntax::parse::token::InternedString; -use utils::span_help_and_lint; +use utils::{span_help_and_lint, span_lint}; use utils::{camel_case_from, camel_case_until}; /// **What it does:** Warns on enum variants that are prefixed or suffixed by the same characters @@ -30,12 +30,14 @@ fn var2str(var: &Variant) -> InternedString { var.node.name.name.as_str() } +/// Returns the number of chars that match from the start fn partial_match(pre: &str, name: &str) -> usize { let mut name_iter = name.chars(); let _ = name_iter.next_back(); // make sure the name is never fully matched pre.chars().zip(name_iter).take_while(|&(l, r)| l == r).count() } +/// Returns the number of chars that match from the end fn partial_rmatch(post: &str, name: &str) -> usize { let mut name_iter = name.chars(); let _ = name_iter.next(); // make sure the name is never fully matched @@ -46,7 +48,20 @@ impl EarlyLintPass for EnumVariantNames { // FIXME: #600 #[allow(while_let_on_iterator)] fn check_item(&mut self, cx: &EarlyContext, item: &Item) { + let item_name = item.ident.name.as_str(); + let item_name_chars = item_name.chars().count(); if let ItemKind::Enum(ref def, _) = item.node { + for var in &def.variants { + let name = var2str(var); + let matching = partial_match(&item_name, &name); + let rmatching = partial_rmatch(&item_name, &name); + if matching == item_name_chars { + span_lint(cx, ENUM_VARIANT_NAMES, var.span, "Variant name starts with the enum's name"); + } + if rmatching == item_name_chars { + span_lint(cx, ENUM_VARIANT_NAMES, var.span, "Variant name ends with the enum's name"); + } + } if def.variants.len() < 2 { return; } diff --git a/tests/compile-fail/enum_variants.rs b/tests/compile-fail/enum_variants.rs index 6589bd35fd3..ed7f7823f8f 100644 --- a/tests/compile-fail/enum_variants.rs +++ b/tests/compile-fail/enum_variants.rs @@ -11,7 +11,8 @@ enum FakeCallType2 { } enum Foo { - cFoo, cBar, + cFoo, //~ ERROR: Variant name ends with the enum's name + cBar, } enum BadCallType { //~ ERROR: All variants have the same prefix: `CallType` @@ -68,4 +69,12 @@ enum NonCaps { //~ ERROR: All variants have the same prefix: `Prefix` PrefixCake, } +enum Stuff { + BadStuff, //~ ERROR: Variant name ends with the enum's name +} + +enum Food { + FoodGood, //~ ERROR: Variant name starts with the enum's name +} + fn main() {}