give FutureIncompatibilityReason variants more explicit names

compiler/rustc_errors/src/diagnostic.rs

@@ -151,7 +151,12 @@ impl fmt::Display for DiagnosticLocation {
 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
 pub enum DiagnosticId {
     Error(String),
-    Lint { name: String, has_future_breakage: bool, is_force_warn: bool },
+    Lint {
+        name: String,
+        /// Indicates whether this lint should show up in cargo's future breakage report.
+        has_future_breakage: bool,
+        is_force_warn: bool,
+    },
 }
 
 /// A "sub"-diagnostic attached to a parent diagnostic.
@@ -301,6 +306,7 @@ impl Diagnostic {
         }
     }
 
+    /// Indicates whether this diagnostic should show up in cargo's future breakage report.
     pub fn has_future_breakage(&self) -> bool {
         match self.code {
             Some(DiagnosticId::Lint { has_future_breakage, .. }) => has_future_breakage,

compiler/rustc_lint/src/array_into_iter.rs

@@ -34,8 +34,8 @@ declare_lint! {
     Warn,
     "detects calling `into_iter` on arrays in Rust 2015 and 2018",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>",
         reason: FutureIncompatibilityReason::EditionSemanticsChange(Edition::Edition2021),
+        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>",
     };
 }
 

compiler/rustc_lint/src/builtin.rs

@@ -844,8 +844,8 @@ declare_lint! {
     Warn,
     "detects anonymous parameters",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
+        reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
     };
 }
 
@@ -1669,8 +1669,8 @@ declare_lint! {
     Warn,
     "`...` range patterns are deprecated",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2021),
+        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>",
     };
 }
 
@@ -1804,8 +1804,8 @@ declare_lint! {
     Allow,
     "detects edition keywords being used as an identifier",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "issue #49716 <https://github.com/rust-lang/rust/issues/49716>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
+        reference: "issue #49716 <https://github.com/rust-lang/rust/issues/49716>",
     };
 }
 

compiler/rustc_lint/src/deref_into_dyn_supertrait.rs

@@ -5,6 +5,7 @@ use crate::{
 
 use rustc_hir as hir;
 use rustc_middle::{traits::util::supertraits, ty};
+use rustc_session::lint::FutureIncompatibilityReason;
 use rustc_span::sym;
 
 declare_lint! {
@@ -48,6 +49,7 @@ declare_lint! {
     Warn,
     "`Deref` implementation usage with a supertrait trait object for output might be shadowed in the future",
     @future_incompatible = FutureIncompatibleInfo {
+        reason: FutureIncompatibilityReason::FutureReleaseErrorDontReportInDeps,
         reference: "issue #89460 <https://github.com/rust-lang/rust/issues/89460>",
     };
 }