diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs index 80909919ba2b6..2a2a9470d25c0 100644 --- a/src/librustdoc/clean/mod.rs +++ b/src/librustdoc/clean/mod.rs @@ -12,7 +12,7 @@ pub(crate) mod utils; use rustc_ast as ast; use rustc_attr as attr; -use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet}; +use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet, IndexEntry}; use rustc_hir as hir; use rustc_hir::def::{CtorKind, DefKind, Res}; use rustc_hir::def_id::{DefId, LOCAL_CRATE}; @@ -598,47 +598,105 @@ pub(crate) fn clean_generics<'tcx>( }) .collect::>(); + let mut bound_predicates = FxIndexMap::default(); + let mut region_predicates = FxIndexMap::default(); + let mut eq_predicates = ThinVec::default(); + for pred in gens.predicates.iter().filter_map(|x| clean_where_predicate(x, cx)) { + match pred { + WherePredicate::BoundPredicate { ty, bounds, bound_params } => { + match bound_predicates.entry(ty) { + IndexEntry::Vacant(v) => { + v.insert((bounds, bound_params)); + } + IndexEntry::Occupied(mut o) => { + // we merge both bounds. + for bound in bounds { + if !o.get().0.contains(&bound) { + o.get_mut().0.push(bound); + } + } + for bound_param in bound_params { + if !o.get().1.contains(&bound_param) { + o.get_mut().1.push(bound_param); + } + } + } + } + } + WherePredicate::RegionPredicate { lifetime, bounds } => { + match region_predicates.entry(lifetime) { + IndexEntry::Vacant(v) => { + v.insert(bounds); + } + IndexEntry::Occupied(mut o) => { + // we merge both bounds. + for bound in bounds { + if !o.get().contains(&bound) { + o.get_mut().push(bound); + } + } + } + } + } + WherePredicate::EqPredicate { lhs, rhs, bound_params } => { + eq_predicates.push(WherePredicate::EqPredicate { lhs, rhs, bound_params }); + } + } + } + let mut params = ThinVec::with_capacity(gens.params.len()); + // In this loop, we gather the generic parameters (`<'a, B: 'a>`) and check if they have + // bounds in the where predicates. If so, we move their bounds into the where predicates + // while also preventing duplicates. for p in gens.params.iter().filter(|p| !is_impl_trait(p) && !is_elided_lifetime(p)) { - let p = clean_generic_param(cx, Some(gens), p); + let mut p = clean_generic_param(cx, Some(gens), p); + match &mut p.kind { + GenericParamDefKind::Lifetime { ref mut outlives } => { + if let Some(region_pred) = region_predicates.get_mut(&Lifetime(p.name)) { + // We merge bounds in the `where` clause. + for outlive in outlives.drain(..) { + let outlive = GenericBound::Outlives(outlive); + if !region_pred.contains(&outlive) { + region_pred.push(outlive); + } + } + } + } + GenericParamDefKind::Type { bounds, synthetic: false, .. } => { + if let Some(bound_pred) = bound_predicates.get_mut(&Type::Generic(p.name)) { + // We merge bounds in the `where` clause. + for bound in bounds.drain(..) { + if !bound_pred.0.contains(&bound) { + bound_pred.0.push(bound); + } + } + } + } + GenericParamDefKind::Type { .. } | GenericParamDefKind::Const { .. } => { + // nothing to do here. + } + } params.push(p); } params.extend(impl_trait_params); - let mut generics = Generics { + Generics { params, - where_predicates: gens - .predicates - .iter() - .filter_map(|x| clean_where_predicate(x, cx)) + where_predicates: bound_predicates + .into_iter() + .map(|(ty, (bounds, bound_params))| WherePredicate::BoundPredicate { + ty, + bounds, + bound_params, + }) + .chain( + region_predicates + .into_iter() + .map(|(lifetime, bounds)| WherePredicate::RegionPredicate { lifetime, bounds }), + ) + .chain(eq_predicates.into_iter()) .collect(), - }; - - // Some duplicates are generated for ?Sized bounds between type params and where - // predicates. The point in here is to move the bounds definitions from type params - // to where predicates when such cases occur. - for where_pred in &mut generics.where_predicates { - match *where_pred { - WherePredicate::BoundPredicate { ty: Generic(ref name), ref mut bounds, .. } => { - if bounds.is_empty() { - for param in &mut generics.params { - match param.kind { - GenericParamDefKind::Lifetime { .. } => {} - GenericParamDefKind::Type { bounds: ref mut ty_bounds, .. } => { - if ¶m.name == name { - mem::swap(bounds, ty_bounds); - break; - } - } - GenericParamDefKind::Const { .. } => {} - } - } - } - } - _ => continue, - } } - generics } fn clean_ty_generics<'tcx>( diff --git a/src/test/rustdoc/bounds-in-multiple-parts.rs b/src/test/rustdoc/bounds-in-multiple-parts.rs new file mode 100644 index 0000000000000..279e3c148887e --- /dev/null +++ b/src/test/rustdoc/bounds-in-multiple-parts.rs @@ -0,0 +1,20 @@ +#![crate_name = "foo"] + +pub trait Eq {} +pub trait Eq2 {} + +// Checking that "where predicates" and "generics params" are merged. +// @has 'foo/trait.T.html' +// @has - "//*[@id='tymethod.f']/h4" "fn f<'a, 'b, 'c, T>()where Self: Eq, T: Eq + 'a, 'c: 'b + 'a," +pub trait T { + fn f<'a, 'b, 'c: 'a, T: Eq + 'a>() + where Self: Eq, Self: Eq, T: Eq, 'c: 'b; +} + +// Checking that a duplicated "where predicate" is removed. +// @has 'foo/trait.T2.html' +// @has - "//*[@id='tymethod.f']/h4" "fn f()where Self: Eq + Eq2, T: Eq2 + Eq," +pub trait T2 { + fn f() + where Self: Eq, Self: Eq2, T: Eq2; +} diff --git a/src/test/rustdoc/impl-parts.rs b/src/test/rustdoc/impl-parts.rs index 7b931727e446d..90cbb77cb6b60 100644 --- a/src/test/rustdoc/impl-parts.rs +++ b/src/test/rustdoc/impl-parts.rs @@ -6,7 +6,7 @@ pub auto trait AnAutoTrait {} pub struct Foo { field: T } // @has impl_parts/struct.Foo.html '//*[@class="impl has-srclink"]//h3[@class="code-header"]' \ -// "impl !AnAutoTrait for Foowhere T: Sync," +// "impl !AnAutoTrait for Foowhere T: Sync + Clone," // @has impl_parts/trait.AnAutoTrait.html '//*[@id="implementors-list"]//h3[@class="code-header"]' \ -// "impl !AnAutoTrait for Foowhere T: Sync," +// "impl !AnAutoTrait for Foowhere T: Sync + Clone," impl !AnAutoTrait for Foo where T: Sync {} diff --git a/src/test/rustdoc/rfc-2632-const-trait-impl.rs b/src/test/rustdoc/rfc-2632-const-trait-impl.rs index 602ee1b1b1fca..7ed9d6729b647 100644 --- a/src/test/rustdoc/rfc-2632-const-trait-impl.rs +++ b/src/test/rustdoc/rfc-2632-const-trait-impl.rs @@ -61,7 +61,7 @@ impl S { // @has - '//section[@id="method.foo"]/h4[@class="code-header"]/a[@class="trait"]' 'Clone' // @!has - '//section[@id="method.foo"]/h4[@class="code-header"]/span[@class="where"]' '~const' // @has - '//section[@id="method.foo"]/h4[@class="code-header"]/span[@class="where fmt-newline"]' ': Clone' - pub const fn foo() + pub const fn foo() where B: ~const Clone + ~const Destruct, { diff --git a/src/test/rustdoc/whitespace-after-where-clause.enum.html b/src/test/rustdoc/whitespace-after-where-clause.enum.html index c74866f4a10b8..f7663e4616ae6 100644 --- a/src/test/rustdoc/whitespace-after-where-clause.enum.html +++ b/src/test/rustdoc/whitespace-after-where-clause.enum.html @@ -1,4 +1,4 @@ -
pub enum Cow<'a, B: ?Sized + 'a>where
    B: ToOwned<dyn Clone>,{
+
pub enum Cow<'a, B>where
    B: ToOwned<dyn Clone> + ?Sized + 'a,{
     Borrowed(&'a B),
     Whatever(u32),
 }

\ No newline at end of file
diff --git a/src/test/rustdoc/whitespace-after-where-clause.struct.html b/src/test/rustdoc/whitespace-after-where-clause.struct.html
index 1ba1367d20f72..fa3f224e7ad0f 100644
--- a/src/test/rustdoc/whitespace-after-where-clause.struct.html
+++ b/src/test/rustdoc/whitespace-after-where-clause.struct.html
@@ -1,4 +1,4 @@
-
pub struct Struct<'a, B: ?Sized + 'a>where
    B: ToOwned<dyn Clone>,{
+
pub struct Struct<'a, B>where
    B: ToOwned<dyn Clone> + ?Sized + 'a,{
     pub a: &'a B,
     pub b: u32,
 }

\ No newline at end of file
diff --git a/src/test/rustdoc/whitespace-after-where-clause.union.html b/src/test/rustdoc/whitespace-after-where-clause.union.html
index 0dfb6407d45f1..7bb177debc3a8 100644
--- a/src/test/rustdoc/whitespace-after-where-clause.union.html
+++ b/src/test/rustdoc/whitespace-after-where-clause.union.html
@@ -1,3 +1,3 @@
-
pub union Union<'a, B: ?Sized + 'a>where
    B: ToOwned<dyn Clone>,{
+
pub union Union<'a, B>where
    B: ToOwned<dyn Clone> + ?Sized + 'a,{
     /* private fields */
 }

\ No newline at end of file