rustdoc: don't inline pub use some_crate unless directly asked to

src/doc/rustdoc/src/the-doc-attribute.md

@@ -186,6 +186,9 @@ mod bar {
 
 Now we'll have a `Re-exports` line, and `Bar` will not link to anywhere.
 
+One special case: In Rust 2018 and later, if you `pub use` one of your dependencies, `rustdoc` will
+not eagerly inline it as a module unless you add `#[doc(inline)}`.
+
 ## `#[doc(hidden)]`
 
 Any item annotated with `#[doc(hidden)]` will not appear in the documentation, unless

src/librustdoc/clean/mod.rs

@@ -3499,13 +3499,16 @@ impl Clean<Vec<Item>> for doctree::Import {
         // forcefully don't inline if this is not public or if the
         // #[doc(no_inline)] attribute is present.
         // Don't inline doc(hidden) imports so they can be stripped at a later stage.
-        let denied = !self.vis.node.is_pub() || self.attrs.iter().any(|a| {
+        let mut denied = !self.vis.node.is_pub() || self.attrs.iter().any(|a| {
             a.name() == "doc" && match a.meta_item_list() {
                 Some(l) => attr::list_contains_name(&l, "no_inline") ||
                            attr::list_contains_name(&l, "hidden"),
                 None => false,
             }
         });
+        // Also check whether imports were asked to be inlined, in case we're trying to re-export a
+        // crate in Rust 2018+
+        let please_inline = self.attrs.lists("doc").has_word("inline");
         let path = self.path.clean(cx);
         let inner = if self.glob {
             if !denied {
@@ -3518,6 +3521,16 @@ impl Clean<Vec<Item>> for doctree::Import {
             Import::Glob(resolve_use_source(cx, path))
         } else {
             let name = self.name;
+            if !please_inline {
+                match path.def {
+                    Def::Mod(did) => if !did.is_local() && did.index == CRATE_DEF_INDEX {
+                        // if we're `pub use`ing an extern crate root, don't inline it unless we
+                        // were specifically asked for it
+                        denied = true;
+                    }
+                    _ => {}
+                }
+            }
             if !denied {
                 let mut visited = FxHashSet::default();
                 if let Some(items) = inline::try_inline(cx, path.def, name, &mut visited) {

src/test/rustdoc/inline_cross/auxiliary/use_crate.rs

@@ -0,0 +1,15 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub mod asdf {
+    pub struct SomeStruct;
+}
+
+pub trait SomeTrait {}

src/test/rustdoc/inline_cross/auxiliary/use_crate_2.rs

@@ -0,0 +1,11 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub struct SomethingElse;

src/test/rustdoc/inline_cross/use_crate.rs

@@ -0,0 +1,37 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:use_crate.rs
+// aux-build:use_crate_2.rs
+// build-aux-docs
+// edition:2018
+// compile-flags:--extern use_crate --extern use_crate_2 -Z unstable-options
+
+// During the buildup to Rust 2018, rustdoc would eagerly inline `pub use some_crate;` as if it
+// were a module, so we changed it to make `pub use`ing crate roots remain as a `pub use` statement
+// in docs... unless you added `#[doc(inline)]`.
+
+#![crate_name = "local"]
+
+// @!has-dir local/use_crate
+// @has local/index.html
+// @has - '//code' 'pub use use_crate'
+pub use use_crate;
+
+// @has-dir local/asdf
+// @has local/asdf/index.html
+// @has local/index.html '//a/@href' 'asdf/index.html'
+pub use use_crate::asdf;
+
+// @has-dir local/use_crate_2
+// @has local/use_crate_2/index.html
+// @has local/index.html '//a/@href' 'use_crate_2/index.html'
+#[doc(inline)]
+pub use use_crate_2;

src/test/rustdoc/src-links-external.rs

@@ -18,6 +18,7 @@
 extern crate src_links_external;
 
 // @has foo/bar/index.html '//a/@href' '../../src/src_links_external/src-links-external.rs.html#11'
+#[doc(inline)]
 pub use src_links_external as bar;
 
 // @has foo/bar/struct.Foo.html '//a/@href' '../../src/src_links_external/src-links-external.rs.html#11'