Auto merge of #4930 - flip1995:unused_label, r=phansch

Deprecate unused_label lint

This lint was uplifted/turned into warn-by-default in rustc

Fixes #4925

changelog: Deprecate [`unused_label`] lint

Author: bors

README.md

@@ -6,7 +6,7 @@
 
 A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code.
 
-[There are 340 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
+[There are 339 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
 
 We have a bunch of lint categories to allow you to choose how much Clippy is supposed to ~~annoy~~ help you:
 

clippy_lints/src/deprecated_lints.rs

@@ -138,3 +138,12 @@ declare_deprecated_lint! {
     pub INTO_ITER_ON_ARRAY,
     "this lint has been uplifted to rustc and is now called `array_into_iter`"
 }
+
+declare_deprecated_lint! {
+    /// **What it does:** Nothing. This lint has been deprecated.
+    ///
+    /// **Deprecation reason:** This lint has been uplifted to rustc and is now called
+    /// `unused_labels`.
+    pub UNUSED_LABEL,
+    "this lint has been uplifted to rustc and is now called `unused_labels`"
+}

clippy_lints/src/lib.rs

@@ -292,7 +292,6 @@ pub mod types;
 pub mod unicode;
 pub mod unsafe_removed_from_name;
 pub mod unused_io_amount;
-pub mod unused_label;
 pub mod unused_self;
 pub mod unwrap;
 pub mod use_self;
@@ -446,6 +445,10 @@ pub fn register_plugins(store: &mut lint::LintStore, sess: &Session, conf: &Conf
         "clippy::into_iter_on_array",
         "this lint has been uplifted to rustc and is now called `array_into_iter`",
     );
+    store.register_removed(
+        "clippy::unused_label",
+        "this lint has been uplifted to rustc and is now called `unused_labels`",
+    );
     // end deprecated lints, do not remove this comment, it’s used in `update_lints`
 
     // begin register lints, do not remove this comment, it’s used in `update_lints`
@@ -774,7 +777,6 @@ pub fn register_plugins(store: &mut lint::LintStore, sess: &Session, conf: &Conf
         &unicode::ZERO_WIDTH_SPACE,
         &unsafe_removed_from_name::UNSAFE_REMOVED_FROM_NAME,
         &unused_io_amount::UNUSED_IO_AMOUNT,
-        &unused_label::UNUSED_LABEL,
         &unused_self::UNUSED_SELF,
         &unwrap::PANICKING_UNWRAP,
         &unwrap::UNNECESSARY_UNWRAP,
@@ -868,7 +870,6 @@ pub fn register_plugins(store: &mut lint::LintStore, sess: &Session, conf: &Conf
     store.register_late_pass(|| box format::UselessFormat);
     store.register_late_pass(|| box swap::Swap);
     store.register_late_pass(|| box overflow_check_conditional::OverflowCheckConditional);
-    store.register_late_pass(|| box unused_label::UnusedLabel);
     store.register_late_pass(|| box new_without_default::NewWithoutDefault::default());
     let blacklisted_names = conf.blacklisted_names.iter().cloned().collect::<FxHashSet<_>>();
     store.register_late_pass(move || box blacklisted_name::BlacklistedName::new(blacklisted_names.clone()));
@@ -1302,7 +1303,6 @@ pub fn register_plugins(store: &mut lint::LintStore, sess: &Session, conf: &Conf
         LintId::of(&unicode::ZERO_WIDTH_SPACE),
         LintId::of(&unsafe_removed_from_name::UNSAFE_REMOVED_FROM_NAME),
         LintId::of(&unused_io_amount::UNUSED_IO_AMOUNT),
-        LintId::of(&unused_label::UNUSED_LABEL),
         LintId::of(&unwrap::PANICKING_UNWRAP),
         LintId::of(&unwrap::UNNECESSARY_UNWRAP),
         LintId::of(&vec::USELESS_VEC),
@@ -1482,7 +1482,6 @@ pub fn register_plugins(store: &mut lint::LintStore, sess: &Session, conf: &Conf
         LintId::of(&types::UNIT_ARG),
         LintId::of(&types::UNNECESSARY_CAST),
         LintId::of(&types::VEC_BOX),
-        LintId::of(&unused_label::UNUSED_LABEL),
         LintId::of(&unwrap::UNNECESSARY_UNWRAP),
         LintId::of(&zero_div_zero::ZERO_DIVIDED_BY_ZERO),
     ]);

clippy_lints/src/unused_label.rs

@@ -6,7 +6,7 @@ pub use lint::Lint;
 pub use lint::LINT_LEVELS;
 
 // begin lint list, do not remove this comment, it’s used in `update_lints`
-pub const ALL_LINTS: [Lint; 340] = [
+pub const ALL_LINTS: [Lint; 339] = [
     Lint {
         name: "absurd_extreme_comparisons",
         group: "correctness",
@@ -2177,13 +2177,6 @@ pub const ALL_LINTS: [Lint; 340] = [
         deprecation: None,
         module: "unused_io_amount",
     },
-    Lint {
-        name: "unused_label",
-        group: "complexity",
-        desc: "unused labels",
-        deprecation: None,
-        module: "unused_label",
-    },
     Lint {
         name: "unused_self",
         group: "pedantic",

src/lintlist/mod.rs

@@ -6,5 +6,6 @@
 #[warn(clippy::unused_collect)]
 #[warn(clippy::invalid_ref)]
 #[warn(clippy::into_iter_on_array)]
+#[warn(clippy::unused_label)]
 
 fn main() {}

tests/ui/deprecated.rs

@@ -48,11 +48,17 @@ error: lint `clippy::into_iter_on_array` has been removed: `this lint has been u
 LL | #[warn(clippy::into_iter_on_array)]
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error: lint `clippy::unused_label` has been removed: `this lint has been uplifted to rustc and is now called `unused_labels``
+  --> $DIR/deprecated.rs:9:8
+   |
+LL | #[warn(clippy::unused_label)]
+   |        ^^^^^^^^^^^^^^^^^^^^
+
 error: lint `clippy::str_to_string` has been removed: `using `str::to_string` is common even today and specialization will likely happen soon`
   --> $DIR/deprecated.rs:1:8
    |
 LL | #[warn(clippy::str_to_string)]
    |        ^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 9 previous errors
+error: aborting due to 10 previous errors
 

tests/ui/deprecated.stderr

@@ -1,7 +1,6 @@
 // aux-build:macro_rules.rs
 
 #![warn(clippy::empty_loop)]
-#![allow(clippy::unused_label)]
 
 #[macro_use]
 extern crate macro_rules;

tests/ui/empty_loop.rs

@@ -1,19 +1,19 @@
 error: empty `loop {}` detected. You may want to either use `panic!()` or add `std::thread::sleep(..);` to the loop body.
-  --> $DIR/empty_loop.rs:10:5
+  --> $DIR/empty_loop.rs:9:5
    |
 LL |     loop {}
    |     ^^^^^^^
    |
    = note: `-D clippy::empty-loop` implied by `-D warnings`
 
 error: empty `loop {}` detected. You may want to either use `panic!()` or add `std::thread::sleep(..);` to the loop body.
-  --> $DIR/empty_loop.rs:12:9
+  --> $DIR/empty_loop.rs:11:9
    |
 LL |         loop {}
    |         ^^^^^^^
 
 error: empty `loop {}` detected. You may want to either use `panic!()` or add `std::thread::sleep(..);` to the loop body.
-  --> $DIR/empty_loop.rs:16:9
+  --> $DIR/empty_loop.rs:15:9
    |
 LL |         'inner: loop {}
    |         ^^^^^^^^^^^^^^^