Auto merge of #3946 - rchaser53:issue-3920, r=flip1995

[rust.git] / clippy_lints / src / empty_enum.rs

diff --git a/clippy_lints/src/empty_enum.rs b/clippy_lints/src/empty_enum.rs
index 896087f47064edde0755eba6d725e6b0d0d33ba5..9075cdc10c8b1b254efbdcd98fef923e374bdefb 100644 (file)
--- a/clippy_lints/src/empty_enum.rs
+++ b/clippy_lints/src/empty_enum.rs
@@ -1,45 +1,53 @@
 //! lint when there is an enum with no variants
 
-use rustc::lint::*;
+use crate::utils::span_lint_and_then;
 use rustc::hir::*;
-use utils::span_lint_and_then;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::{declare_tool_lint, lint_array};
 
-/// **What it does:** Checks for `enum`s with no variants.
-///
-/// **Why is this bad?** Enum's with no variants should be replaced with `!`, the uninhabited type,
-/// or a wrapper around it.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// enum Test {}
-/// ```
-declare_lint! {
+declare_clippy_lint! {
+    /// **What it does:** Checks for `enum`s with no variants.
+    ///
+    /// **Why is this bad?** Enum's with no variants should be replaced with `!`,
+    /// the uninhabited type,
+    /// or a wrapper around it.
+    ///
+    /// **Known problems:** None.
+    ///
+    /// **Example:**
+    /// ```rust
+    /// enum Test {}
+    /// ```
     pub EMPTY_ENUM,
-    Allow,
+    pedantic,
     "enum with no variants"
 }
 
-#[derive(Copy,Clone)]
+#[derive(Copy, Clone)]
 pub struct EmptyEnum;
 
 impl LintPass for EmptyEnum {
     fn get_lints(&self) -> LintArray {
         lint_array!(EMPTY_ENUM)
     }
+
+    fn name(&self) -> &'static str {
+        "EmptyEnum"
+    }
 }
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for EmptyEnum {
-    fn check_item(&mut self, cx: &LateContext, item: &Item) {
-        let did = cx.tcx.hir.local_def_id(item.id);
-        if let ItemEnum(..) = item.node {
-            let ty = cx.tcx.item_type(did);
+    fn check_item(&mut self, cx: &LateContext<'_, '_>, item: &Item) {
+        let did = cx.tcx.hir().local_def_id_from_hir_id(item.hir_id);
+        if let ItemKind::Enum(..) = item.node {
+            let ty = cx.tcx.type_of(did);
             let adt = ty.ty_adt_def().expect("already checked whether this is an enum");
             if adt.variants.is_empty() {
                 span_lint_and_then(cx, EMPTY_ENUM, item.span, "enum with no variants", |db| {
-                    db.span_help(item.span,
-                                 "consider using the uninhabited type `!` or a wrapper around it");
+                    db.span_help(
+                        item.span,
+                        "consider using the uninhabited type `!` or a wrapper around it",
+                    );
                 });
             }
         }