rustdoc: inherit parent's stability where applicable

compiler/rustc_attr/src/builtin.rs

@@ -153,7 +153,7 @@ pub enum StabilityLevel {
 }
 
 /// Rust release in which a feature is stabilized.
-#[derive(Encodable, Decodable, PartialEq, Copy, Clone, Debug, Eq, Hash)]
+#[derive(Encodable, Decodable, PartialEq, Copy, Clone, Debug, Eq, PartialOrd, Ord, Hash)]
 #[derive(HashStable_Generic)]
 pub enum StableSince {
  Version(RustcVersion),

src/librustdoc/clean/types.rs

@@ -384,7 +384,45 @@ fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
 
 impl Item {
  pub(crate) fn stability(&self, tcx: TyCtxt<'_>) -> Option<Stability> {
- self.def_id().and_then(|did| tcx.lookup_stability(did))
+ let (mut def_id, mut stability) = if let Some(inlined) = self.inline_stmt_id {
+ let inlined_def_id = inlined.to_def_id();
+ if let Some(stability) = tcx.lookup_stability(inlined_def_id) {
+ (inlined_def_id, stability)
+ } else {
+ // For re-exports into crates without `staged_api`, reuse the original stability.
+ // This is necessary, because we always want to mark unstable items.
+ let def_id = self.def_id()?;
+ return tcx.lookup_stability(def_id);
+ }
+ } else {
+ let def_id = self.def_id()?;
+ let stability = tcx.lookup_stability(def_id)?;
+ (def_id, stability)
+ };
+
+ let StabilityLevel::Stable { mut since, allowed_through_unstable_modules: false } =
+ stability.level
+ else {
+ return Some(stability);
+ };
+
+ // If any of the item's ancestors was stabilized later or is still unstable,
+ // then report the ancestor's stability instead.
+ while let Some(parent_def_id) = tcx.opt_parent(def_id) {
+ if let Some(parent_stability) = tcx.lookup_stability(parent_def_id) {
+ match parent_stability.level {
+ StabilityLevel::Unstable { .. } => return Some(parent_stability),
+ StabilityLevel::Stable { since: parent_since, .. } => {
+ if parent_since > since {
+ stability = parent_stability;
+ since = parent_since;
+ }
+ }
+ }
+ }
+ def_id = parent_def_id;
+ }
+ Some(stability)
  }
 
  pub(crate) fn const_stability(&self, tcx: TyCtxt<'_>) -> Option<ConstStability> {

tests/rustdoc/const-display.rs

@@ -1,8 +1,6 @@
 #![crate_name = "foo"]
 
-#![unstable(feature = "humans",
- reason = "who ever let humans program computers, we're apparently really bad at it",
- issue = "none")]
+#![stable(feature = "rust1", since = "1.0.0")]
 
 #![feature(foo, foo2)]
 #![feature(staged_api)]
@@ -48,10 +46,18 @@ pub const unsafe fn foo2_gated() -> u32 { 42 }
 #[rustc_const_stable(feature = "rust1", since = "1.0.0")]
 pub const unsafe fn bar2_gated() -> u32 { 42 }
 
-//@ has 'foo/fn.bar_not_gated.html' '//pre' 'pub const unsafe fn bar_not_gated() -> u32'
-//@ !hasraw - '//span[@class="since"]'
-pub const unsafe fn bar_not_gated() -> u32 { 42 }
+#[unstable(
+ feature = "humans",
+ reason = "who ever let humans program computers, we're apparently really bad at it",
+ issue = "none",
+)]
+pub mod unstable {
+ //@ has 'foo/unstable/fn.bar_not_gated.html' '//pre' 'pub const unsafe fn bar_not_gated() -> u32'
+ //@ !hasraw - '//span[@class="since"]'
+ pub const unsafe fn bar_not_gated() -> u32 { 42 }
+}
 
+#[stable(feature = "rust1", since = "1.0.0")]
 pub struct Foo;
 
 impl Foo {

tests/rustdoc/stability.rs

@@ -1,6 +1,6 @@
 #![feature(staged_api)]
 
-#![unstable(feature = "test", issue = "none")]
+#![stable(feature = "rust1", since = "1.0.0")]
 
 //@ has stability/index.html
 //@ has - '//ul[@class="item-table"]/li[1]//a' AaStable
@@ -10,6 +10,7 @@
 #[stable(feature = "rust2", since = "2.2.2")]
 pub struct AaStable;
 
+#[unstable(feature = "test", issue = "none")]
 pub struct Unstable {
  //@ has stability/struct.Unstable.html \
  // '//span[@class="item-info"]//div[@class="stab unstable"]' \
@@ -21,3 +22,31 @@ pub struct Unstable {
 
 #[stable(feature = "rust2", since = "2.2.2")]
 pub struct ZzStable;
+
+#[unstable(feature = "unstable", issue = "none")]
+pub mod unstable {
+ //@ !hasraw stability/unstable/struct.Foo.html '//span[@class="since"]'
+ //@ has - '//div[@class="stab unstable"]' 'experimental'
+ #[stable(feature = "rust1", since = "1.0.0")]
+ pub struct Foo;
+}
+
+#[stable(feature = "rust2", since = "2.2.2")]
+pub mod stable_later {
+ //@ has stability/stable_later/struct.Bar.html '//span[@class="since"]' '2.2.2'
+ #[stable(feature = "rust1", since = "1.0.0")]
+ pub struct Bar;
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+pub mod stable_earlier {
+ //@ has stability/stable_earlier/struct.Foo.html '//span[@class="since"]' '1.0.0'
+ #[doc(inline)]
+ #[stable(feature = "rust1", since = "1.0.0")]
+ pub use crate::unstable::Foo;
+
+ //@ has stability/stable_earlier/struct.Bar.html '//span[@class="since"]' '1.0.0'
+ #[doc(inline)]
+ #[stable(feature = "rust1", since = "1.0.0")]
+ pub use crate::stable_later::Bar;
+}