Feature gate the non_exhaustive_omitted_patterns lint

compiler/rustc_feature/src/active.rs

@@ -678,6 +678,9 @@ declare_features! (
     /// Allows `#[doc(cfg_hide(...))]`.
     (active, doc_cfg_hide, "1.57.0", Some(43781), None),
 
+    /// Allows using the `non_exhaustive_omitted_patterns` lint.
+    (active, non_exhaustive_omitted_patterns_lint, "1.57.0", Some(89554), None),
+
     // -------------------------------------------------------------------------
     // feature-group-end: actual feature gates
     // -------------------------------------------------------------------------

compiler/rustc_lint_defs/src/builtin.rs

@@ -6,6 +6,7 @@
 
 use crate::{declare_lint, declare_lint_pass, FutureIncompatibilityReason};
 use rustc_span::edition::Edition;
+use rustc_span::symbol::sym;
 
 declare_lint! {
     /// The `forbidden_lint_groups` lint detects violations of
@@ -3476,6 +3477,8 @@ declare_lint! {
     /// }
     ///
     /// // in crate B
+    /// #![feature(non_exhaustive_omitted_patterns_lint)]
+    ///
     /// match Bar::A {
     ///     Bar::A => {},
     ///     #[warn(non_exhaustive_omitted_patterns)]
@@ -3512,6 +3515,7 @@ declare_lint! {
     pub NON_EXHAUSTIVE_OMITTED_PATTERNS,
     Allow,
     "detect when patterns of types marked `non_exhaustive` are missed",
+    @feature_gate = sym::non_exhaustive_omitted_patterns_lint;
 }
 
 declare_lint! {

compiler/rustc_span/src/symbol.rs

@@ -893,6 +893,7 @@ symbols! {
         nomem,
         non_ascii_idents,
         non_exhaustive,
+        non_exhaustive_omitted_patterns_lint,
         non_modrs_mods,
         none_error,
         nontemporal_store,

src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs

@@ -0,0 +1,31 @@
+#![deny(non_exhaustive_omitted_patterns)]
+//~^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+//~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+#![allow(non_exhaustive_omitted_patterns)]
+//~^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+//~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+
+fn main() {
+    enum Foo {
+        A, B, C,
+    }
+
+    #[allow(non_exhaustive_omitted_patterns)]
+    match Foo::A {
+        Foo::A => {}
+        Foo::B => {}
+    }
+    //~^^^^^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+
+    match Foo::A {
+        Foo::A => {}
+        Foo::B => {}
+        #[warn(non_exhaustive_omitted_patterns)]
+        _ => {}
+    }
+    //~^^^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+}

src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr

@@ -0,0 +1,93 @@
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:1:1
+   |
+LL | #![deny(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:4:1
+   |
+LL | #![allow(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:26:9
+   |
+LL |         #[warn(non_exhaustive_omitted_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:1:1
+   |
+LL | #![deny(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:4:1
+   |
+LL | #![allow(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:26:9
+   |
+LL |         #[warn(non_exhaustive_omitted_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error: aborting due to 10 previous errors
+
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.rs

@@ -1,5 +1,7 @@
 // Test that the `non_exhaustive_omitted_patterns` lint is triggered correctly.
 
+#![feature(non_exhaustive_omitted_patterns_lint)]
+
 // aux-build:enums.rs
 extern crate enums;
 

src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.stderr

@@ -1,47 +1,47 @@
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:127:9
+  --> $DIR/reachable-patterns.rs:129:9
    |
 LL |         VariantNonExhaustive::Bar { x, .. } => {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `y` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:124:12
+  --> $DIR/reachable-patterns.rs:126:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all fields are mentioned explicitly by adding the suggested fields
    = note: the pattern is of type `VariantNonExhaustive` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:132:9
+  --> $DIR/reachable-patterns.rs:134:9
    |
 LL |     let FunctionalRecord { first_field, second_field, .. } = FunctionalRecord::default();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `third_field` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:131:12
+  --> $DIR/reachable-patterns.rs:133:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all fields are mentioned explicitly by adding the suggested fields
    = note: the pattern is of type `FunctionalRecord` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:140:29
+  --> $DIR/reachable-patterns.rs:142:29
    |
 LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = NestedStruct::default();
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `second_field` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:139:12
+  --> $DIR/reachable-patterns.rs:141:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all fields are mentioned explicitly by adding the suggested fields
    = note: the pattern is of type `NormalStruct` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:140:9
+  --> $DIR/reachable-patterns.rs:142:9
    |
 LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = NestedStruct::default();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `foo` not listed
@@ -50,63 +50,63 @@ LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = Nested
    = note: the pattern is of type `NestedStruct` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:54:9
+  --> $DIR/reachable-patterns.rs:56:9
    |
 LL |         _ => {}
    |         ^ pattern `Struct { .. }` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:53:16
+  --> $DIR/reachable-patterns.rs:55:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all variants are matched explicitly by adding the suggested match arms
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:61:9
+  --> $DIR/reachable-patterns.rs:63:9
    |
 LL |         _ => {}
    |         ^ pattern `Tuple(_)` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:60:16
+  --> $DIR/reachable-patterns.rs:62:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all variants are matched explicitly by adding the suggested match arms
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:71:9
+  --> $DIR/reachable-patterns.rs:73:9
    |
 LL |         _ => {}
    |         ^ pattern `Unit` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:70:16
+  --> $DIR/reachable-patterns.rs:72:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all variants are matched explicitly by adding the suggested match arms
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:88:32
+  --> $DIR/reachable-patterns.rs:90:32
    |
 LL |         NestedNonExhaustive::A(_) => {}
    |                                ^ patterns `Tuple(_)` and `Struct { .. }` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:85:12
+  --> $DIR/reachable-patterns.rs:87:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all variants are matched explicitly by adding the suggested match arms
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:90:9
+  --> $DIR/reachable-patterns.rs:92:9
    |
 LL |         _ => {}
    |         ^ pattern `C` not covered
@@ -115,27 +115,27 @@ LL |         _ => {}
    = note: the matched value is of type `NestedNonExhaustive` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:120:9
+  --> $DIR/reachable-patterns.rs:122:9
    |
 LL |         _ => {}
    |         ^ patterns `HostUnreachable`, `NetworkUnreachable`, `NetworkDown` and 18 more not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:97:12
+  --> $DIR/reachable-patterns.rs:99:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: ensure that all variants are matched explicitly by adding the suggested match arms
    = note: the matched value is of type `ErrorKind` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:157:9
+  --> $DIR/reachable-patterns.rs:159:9
    |
 LL |         _ => {}
    |         ^ pattern `A(_)` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:155:12
+  --> $DIR/reachable-patterns.rs:157:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^