62 lines
1.6 KiB
Rust
62 lines
1.6 KiB
Rust
//! lint on `use`ing all variants of an enum
|
|
|
|
use rustc::hir::*;
|
|
use rustc::hir::def::Def;
|
|
use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
|
|
use syntax::ast::NodeId;
|
|
use syntax::codemap::Span;
|
|
use crate::utils::span_lint;
|
|
|
|
/// **What it does:** Checks for `use Enum::*`.
|
|
///
|
|
/// **Why is this bad?** It is usually better style to use the prefixed name of
|
|
/// an enumeration variant, rather than importing variants.
|
|
///
|
|
/// **Known problems:** Old-style enumerations that prefix the variants are
|
|
/// still around.
|
|
///
|
|
/// **Example:**
|
|
/// ```rust
|
|
/// use std::cmp::Ordering::*;
|
|
/// ```
|
|
declare_clippy_lint! {
|
|
pub ENUM_GLOB_USE,
|
|
pedantic,
|
|
"use items that import all variants of an enum"
|
|
}
|
|
|
|
pub struct EnumGlobUse;
|
|
|
|
impl LintPass for EnumGlobUse {
|
|
fn get_lints(&self) -> LintArray {
|
|
lint_array!(ENUM_GLOB_USE)
|
|
}
|
|
}
|
|
|
|
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for EnumGlobUse {
|
|
fn check_mod(&mut self, cx: &LateContext<'a, 'tcx>, m: &'tcx Mod, _: Span, _: NodeId) {
|
|
// only check top level `use` statements
|
|
for item in &m.item_ids {
|
|
self.lint_item(cx, cx.tcx.hir.expect_item(item.id));
|
|
}
|
|
}
|
|
}
|
|
|
|
impl EnumGlobUse {
|
|
fn lint_item(&self, cx: &LateContext, item: &Item) {
|
|
if item.vis == Visibility::Public {
|
|
return; // re-exports are fine
|
|
}
|
|
if let ItemUse(ref path, UseKind::Glob) = item.node {
|
|
if let Def::Enum(_) = path.def {
|
|
span_lint(
|
|
cx,
|
|
ENUM_GLOB_USE,
|
|
item.span,
|
|
"don't use glob imports for enum variants",
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|