Rollup merge of rust-lang#112836 - GuillaumeGomez:rustdoc-invalid-file-creation, r=notriddle

[rustdoc] partially fix invalid files creation

Part of rust-lang#111249. It only removes generation for modules which shouldn't exist. For files, we need the compiler to keep re-export information alive for external items so we can actually have the right path to their ___location as it's currently not generating them correctly.

In case the item is inlined, it shouldn't (and neither should its children) get a file generated.

r? ```@notriddle```

Author: GuillaumeGomez

src/librustdoc/clean/types.rs

@@ -358,15 +358,15 @@ fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
 
 impl Item {
     pub(crate) fn stability<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option<Stability> {
-        self.item_id.as_def_id().and_then(|did| tcx.lookup_stability(did))
+        self.def_id().and_then(|did| tcx.lookup_stability(did))
     }
 
     pub(crate) fn const_stability<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option<ConstStability> {
-        self.item_id.as_def_id().and_then(|did| tcx.lookup_const_stability(did))
+        self.def_id().and_then(|did| tcx.lookup_const_stability(did))
     }
 
     pub(crate) fn deprecation(&self, tcx: TyCtxt<'_>) -> Option<Deprecation> {
-        self.item_id.as_def_id().and_then(|did| tcx.lookup_deprecation(did))
+        self.def_id().and_then(|did| tcx.lookup_deprecation(did))
     }
 
     pub(crate) fn inner_docs(&self, tcx: TyCtxt<'_>) -> bool {
@@ -391,7 +391,7 @@ impl Item {
                     panic!("blanket impl item has non-blanket ID")
                 }
             }
-            _ => self.item_id.as_def_id().map(|did| rustc_span(did, tcx)),
+            _ => self.def_id().map(|did| rustc_span(did, tcx)),
         }
     }
 
@@ -501,7 +501,7 @@ impl Item {
     }
 
     pub(crate) fn is_crate(&self) -> bool {
-        self.is_mod() && self.item_id.as_def_id().map_or(false, |did| did.is_crate_root())
+        self.is_mod() && self.def_id().map_or(false, |did| did.is_crate_root())
     }
     pub(crate) fn is_mod(&self) -> bool {
         self.type_() == ItemType::Module
@@ -638,11 +638,11 @@ impl Item {
         }
         let header = match *self.kind {
             ItemKind::ForeignFunctionItem(_) => {
-                let def_id = self.item_id.as_def_id().unwrap();
+                let def_id = self.def_id().unwrap();
                 let abi = tcx.fn_sig(def_id).skip_binder().abi();
                 hir::FnHeader {
                     unsafety: if abi == Abi::RustIntrinsic {
-                        intrinsic_operation_unsafety(tcx, self.item_id.as_def_id().unwrap())
+                        intrinsic_operation_unsafety(tcx, self.def_id().unwrap())
                     } else {
                         hir::Unsafety::Unsafe
                     },
@@ -659,7 +659,7 @@ impl Item {
                 }
             }
             ItemKind::FunctionItem(_) | ItemKind::MethodItem(_, _) | ItemKind::TyMethodItem(_) => {
-                let def_id = self.item_id.as_def_id().unwrap();
+                let def_id = self.def_id().unwrap();
                 build_fn_header(def_id, tcx, tcx.asyncness(def_id))
             }
             _ => return None,
@@ -738,7 +738,7 @@ impl Item {
                 }
             })
             .collect();
-        if let Some(def_id) = self.item_id.as_def_id() &&
+        if let Some(def_id) = self.def_id() &&
             !def_id.is_local() &&
             // This check is needed because `adt_def` will panic if not a compatible type otherwise...
             matches!(self.type_(), ItemType::Struct | ItemType::Enum | ItemType::Union)
@@ -787,6 +787,10 @@ impl Item {
     pub fn is_doc_hidden(&self) -> bool {
         self.attrs.is_doc_hidden()
     }
+
+    pub fn def_id(&self) -> Option<DefId> {
+        self.item_id.as_def_id()
+    }
 }
 
 #[derive(Clone, Debug)]

src/librustdoc/formats/cache.rs

@@ -121,6 +121,11 @@ pub(crate) struct Cache {
     pub(crate) intra_doc_links: FxHashMap<ItemId, FxIndexSet<clean::ItemLink>>,
     /// Cfg that have been hidden via #![doc(cfg_hide(...))]
     pub(crate) hidden_cfg: FxHashSet<clean::cfg::Cfg>,
+
+    /// Contains the list of `DefId`s which have been inlined. It is used when generating files
+    /// to check if a stripped item should get its file generated or not: if it's inside a
+    /// `#[doc(hidden)]` item or a private one and not inlined, it shouldn't get a file.
+    pub(crate) inlined_items: DefIdSet,
 }
 
 /// This struct is used to wrap the `cache` and `tcx` in order to run `DocFolder`.

src/librustdoc/html/render/context.rs

@@ -73,6 +73,8 @@ pub(crate) struct Context<'tcx> {
     pub(crate) include_sources: bool,
     /// Collection of all types with notable traits referenced in the current module.
     pub(crate) types_with_notable_traits: FxHashSet<clean::Type>,
+    /// Field used during rendering, to know if we're inside an inlined item.
+    pub(crate) is_inside_inlined_module: bool,
 }
 
 // `Context` is cloned a lot, so we don't want the size to grow unexpectedly.
@@ -171,6 +173,19 @@ impl<'tcx> Context<'tcx> {
     }
 
     fn render_item(&mut self, it: &clean::Item, is_module: bool) -> String {
+        let mut render_redirect_pages = self.render_redirect_pages;
+        // If the item is stripped but inlined, links won't point to the item so no need to generate
+        // a file for it.
+        if it.is_stripped() &&
+            let Some(def_id) = it.def_id() &&
+            def_id.is_local()
+        {
+            if self.is_inside_inlined_module || self.shared.cache.inlined_items.contains(&def_id) {
+                // For now we're forced to generate a redirect page for stripped items until
+                // `record_extern_fqn` correctly points to external items.
+                render_redirect_pages = true;
+            }
+        }
         let mut title = String::new();
         if !is_module {
             title.push_str(it.name.unwrap().as_str());
@@ -205,7 +220,7 @@ impl<'tcx> Context<'tcx> {
             tyname.as_str()
         };
 
-        if !self.render_redirect_pages {
+        if !render_redirect_pages {
             let clone_shared = Rc::clone(&self.shared);
             let page = layout::Page {
                 css_class: tyname_s,
@@ -545,6 +560,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             shared: Rc::new(scx),
             include_sources,
             types_with_notable_traits: FxHashSet::default(),
+            is_inside_inlined_module: false,
         };
 
         if emit_crate {
@@ -574,6 +590,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             shared: Rc::clone(&self.shared),
             include_sources: self.include_sources,
             types_with_notable_traits: FxHashSet::default(),
+            is_inside_inlined_module: self.is_inside_inlined_module,
         }
     }
 
@@ -768,12 +785,22 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
 
         info!("Recursing into {}", self.dst.display());
 
-        let buf = self.render_item(item, true);
-        // buf will be empty if the module is stripped and there is no redirect for it
-        if !buf.is_empty() {
-            self.shared.ensure_dir(&self.dst)?;
-            let joint_dst = self.dst.join("index.html");
-            self.shared.fs.write(joint_dst, buf)?;
+        if !item.is_stripped() {
+            let buf = self.render_item(item, true);
+            // buf will be empty if the module is stripped and there is no redirect for it
+            if !buf.is_empty() {
+                self.shared.ensure_dir(&self.dst)?;
+                let joint_dst = self.dst.join("index.html");
+                self.shared.fs.write(joint_dst, buf)?;
+            }
+        }
+        if !self.is_inside_inlined_module {
+            if let Some(def_id) = item.def_id() && self.cache().inlined_items.contains(&def_id) {
+                self.is_inside_inlined_module = true;
+            }
+        } else if item.is_doc_hidden() {
+            // We're not inside an inlined module anymore since this one cannot be re-exported.
+            self.is_inside_inlined_module = false;
         }
 
         // Render sidebar-items.js used throughout this module.

src/librustdoc/visit_ast.rs

@@ -313,7 +313,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             return false;
         }
 
-        let ret = match tcx.hir().get_by_def_id(res_did) {
+        let inlined = match tcx.hir().get_by_def_id(res_did) {
             // Bang macros are handled a bit on their because of how they are handled by the
             // compiler. If they have `#[doc(hidden)]` and the re-export doesn't have
             // `#[doc(inline)]`, then we don't inline it.
@@ -344,7 +344,10 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             _ => false,
         };
         self.view_item_stack.remove(&res_did);
-        ret
+        if inlined {
+            self.cx.cache.inlined_items.insert(res_did.to_def_id());
+        }
+        inlined
     }
 
     /// Returns `true` if the item is visible, meaning it's not `#[doc(hidden)]` or private.

tests/rustdoc/files-creation-hidden.rs

@@ -0,0 +1,23 @@
+#![crate_name="foo"]
+
+// @!has "foo/struct.Foo.html"
+#[doc(hidden)]
+pub struct Foo;
+
+// @!has "foo/struct.Bar.html"
+pub use crate::Foo as Bar;
+
+// @!has "foo/struct.Baz.html"
+#[doc(hidden)]
+pub use crate::Foo as Baz;
+
+// @!has "foo/foo/index.html"
+#[doc(hidden)]
+pub mod foo {}
+
+// @!has "foo/bar/index.html"
+pub use crate::foo as bar;
+
+// @!has "foo/baz/index.html"
+#[doc(hidden)]
+pub use crate::foo as baz;

tests/rustdoc/files-creation-private.rs

@@ -0,0 +1,18 @@
+#![crate_name="foo"]
+
+// @!has "foo/priv/index.html"
+// @!has "foo/priv/struct.Foo.html"
+mod private {
+    pub struct Foo;
+}
+
+// @has "foo/struct.Bar.html"
+pub use crate::private::Foo as Bar;
+
+// @!has "foo/foo/index.html"
+mod foo {
+    pub mod subfoo {}
+}
+
+// @has "foo/bar/index.html"
+pub use crate::foo::subfoo as bar;

tests/rustdoc/issue-111064-reexport-trait-from-hidden-2.rs

@@ -3,10 +3,10 @@
 #![crate_name = "foo"]
 
 // @!has 'foo/hidden/index.html'
-// FIXME: add missing `@` for the two next tests once issue is fixed!
-// To be done in <https://github.com/rust-lang/rust/issues/111249>.
-// !has 'foo/hidden/inner/index.html'
-// !has 'foo/hidden/inner/trait.Foo.html'
+// @!has 'foo/hidden/inner/index.html'
+// FIXME: Should be `@!has`: https://github.com/rust-lang/rust/issues/111249
+// @has 'foo/hidden/inner/trait.Foo.html'
+// @matchesraw - '<meta http-equiv="refresh" content="0;URL=../../../foo/visible/trait.Foo.html">'
 #[doc(hidden)]
 pub mod hidden {
     pub mod inner {

tests/rustdoc/issue-111249-file-creation.rs

@@ -0,0 +1,34 @@
+#![crate_name = "foo"]
+#![feature(no_core)]
+#![no_core]
+
+// The following five should not fail!
+// @!has 'foo/hidden/index.html'
+// @!has 'foo/hidden/inner/index.html'
+// FIXME: Should be `@!has`: https://github.com/rust-lang/rust/issues/111249
+// @has 'foo/hidden/inner/trait.Foo.html'
+// @matchesraw - '<meta http-equiv="refresh" content="0;URL=../../../foo/visible/trait.Foo.html">'
+// @!has 'foo/hidden/inner/inner_hidden/index.html'
+// @!has 'foo/hidden/inner/inner_hidden/trait.HiddenFoo.html'
+#[doc(hidden)]
+pub mod hidden {
+    pub mod inner {
+        pub trait Foo {}
+
+        #[doc(hidden)]
+        pub mod inner_hidden {
+            pub trait HiddenFoo {}
+        }
+    }
+}
+
+// @has 'foo/visible/index.html'
+// @has 'foo/visible/trait.Foo.html'
+#[doc(inline)]
+pub use hidden::inner as visible;
+
+// @has 'foo/struct.Bar.html'
+// @count - '//*[@id="impl-Foo-for-Bar"]' 1
+pub struct Bar;
+
+impl visible::Foo for Bar {}

tests/rustdoc/redirect.rs

@@ -10,7 +10,9 @@ pub trait Foo {}
 // @has - '//code' 'pub use reexp_stripped::Bar'
 // @has - '//code/a' 'Bar'
 // @has - '//a[@href="../reexp_stripped/hidden/struct.Bar.html"]' 'Bar'
+// FIXME: Should be `@!has`: https://github.com/rust-lang/rust/issues/111249
 // @has reexp_stripped/hidden/struct.Bar.html
+// @matchesraw - '<meta http-equiv="refresh" content="0;URL=../../reexp_stripped/struct.Bar.html">'
 // @has 'reexp_stripped/struct.Bar.html'
 // @has - '//a[@href="struct.Bar.html"]' 'Bar'
 #[doc(no_inline)]