Migrate unstable-book to MdBook2

src/bootstrap/doc.rs

@@ -134,7 +134,7 @@ impl Step for UnstableBook {
             target: self.target,
             name: INTERNER.intern_str("unstable-book"),
             src: builder.md_doc_out(self.target),
-            version: RustbookVersion::MdBook1,
+            version: RustbookVersion::MdBook2,
         })
     }
 }

src/doc/unstable-book/src/language-features/asm.md

@@ -190,4 +190,4 @@ constraints, etc.
 [llvm-docs]: http://llvm.org/docs/LangRef.html#inline-assembler-expressions
 
 If you need more power and don't mind losing some of the niceties of
-`asm!`, check out [global_asm](language-features/global-asm.html).
+`asm!`, check out [global_asm](global-asm.md).

src/doc/unstable-book/src/language-features/box-patterns.md

@@ -4,7 +4,7 @@ The tracking issue for this feature is: [#29641]
 
 [#29641]: https://github.com/rust-lang/rust/issues/29641
 
-See also [`box_syntax`](language-features/box-syntax.html)
+See also [`box_syntax`](box-syntax.md)
 
 ------------------------
 

src/doc/unstable-book/src/language-features/box-syntax.md

@@ -4,7 +4,7 @@ The tracking issue for this feature is: [#49733]
 
 [#49733]: https://github.com/rust-lang/rust/issues/49733
 
-See also [`box_patterns`](language-features/box-patterns.html)
+See also [`box_patterns`](box-patterns.md)
 
 ------------------------
 

src/doc/unstable-book/src/language-features/global-asm.md

@@ -75,4 +75,4 @@ usages and placed the larger, single usage in the crate root.
 If you don't need quite as much power and flexibility as
 `global_asm!` provides, and you don't mind restricting your inline
 assembly to `fn` bodies only, you might try the
-[asm](language-features/asm.html) feature instead.
+[asm](asm.md) feature instead.

src/doc/unstable-book/src/language-features/lang-items.md

@@ -192,7 +192,7 @@ such as "```undefined reference to `__rust_probestack'```". Using this crate
 also requires enabling the library feature `compiler_builtins_lib`. You can read
 more about this [here][compiler-builtins-lib].
 
-[compiler-builtins-lib]: library-features/compiler-builtins-lib.html
+[compiler-builtins-lib]: ../library-features/compiler-builtins-lib.md
 
 ## More about the language items
 

src/doc/unstable-book/src/language-features/non-ascii-idents.md

@@ -45,4 +45,4 @@ that does _not_ occur in the set of [strict keywords].
 
 [`XID_start`]:  http://unicode.org/cldr/utility/list-unicodeset.jsp?a=%5B%3AXID_Start%3A%5D&abb=on&g=&i=
 [`XID_continue`]: http://unicode.org/cldr/utility/list-unicodeset.jsp?a=%5B%3AXID_Continue%3A%5D&abb=on&g=&i=
-[strict keywords]: ../reference/keywords.html#strict-keywords
+[strict keywords]: ../../reference/keywords.md#strict-keywords

src/doc/unstable-book/src/language-features/plugin-registrar.md

@@ -8,6 +8,6 @@ This feature is part of "compiler plugins." It will often be used with the
 [`plugin`] and `rustc_private` features as well. For more details, see
 their docs.
 
-[`plugin`]: language-features/plugin.html
+[`plugin`]: plugin.md
 
 ------------------------

src/doc/unstable-book/src/language-features/plugin.md

@@ -8,7 +8,7 @@ The tracking issue for this feature is: [#29597]
 This feature is part of "compiler plugins." It will often be used with the
 [`plugin_registrar`] and `rustc_private` features.
 
-[`plugin_registrar`]: language-features/plugin-registrar.html
+[`plugin_registrar`]: plugin-registrar.md
 
 ------------------------
 
@@ -39,7 +39,7 @@ of a library.
 
 Plugins can extend Rust's syntax in various ways. One kind of syntax extension
 is the procedural macro. These are invoked the same way as [ordinary
-macros](../book/macros.html), but the expansion is performed by arbitrary Rust
+macros](../../book/macros.md), but the expansion is performed by arbitrary Rust
 code that manipulates syntax trees at
 compile time.
 
@@ -130,7 +130,7 @@ The advantages over a simple `fn(&str) -> u32` are:
   a way to define new literal syntax for any data type.
 
 In addition to procedural macros, you can define new
-[`derive`](../reference/attributes/derive.html)-like attributes and other kinds
+[`derive`](../../reference/attributes/derive.md)-like attributes and other kinds
 of extensions.  See `Registry::register_syntax_extension` and the
 `SyntaxExtension` enum.  For a more involved macro example, see
 [`regex_macros`](https://github.com/rust-lang/regex/blob/master/regex_macros/src/lib.rs).
@@ -174,7 +174,7 @@ quasiquote as an ordinary plugin library.
 # Lint plugins
 
 Plugins can extend [Rust's lint
-infrastructure](../reference/attributes/diagnostics.html#lint-check-attributes) with
+infrastructure](../../reference/attributes/diagnostics.md#lint-check-attributes) with
 additional checks for code style, safety, etc. Now let's write a plugin
 [`lint_plugin_test.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui-fulldeps/auxiliary/lint_plugin_test.rs)
 that warns about any item named `lintme`.
@@ -253,7 +253,7 @@ mostly use the same infrastructure as lint plugins, and provide examples of how
 to access type information.
 
 Lints defined by plugins are controlled by the usual [attributes and compiler
-flags](../reference/attributes/diagnostics.html#lint-check-attributes), e.g.
+flags](../../reference/attributes/diagnostics.md#lint-check-attributes), e.g.
 `#[allow(test_lint)]` or `-A test-lint`. These identifiers are derived from the
 first argument to `declare_lint!`, with appropriate case and punctuation
 conversion.

src/doc/unstable-book/src/language-features/unboxed-closures.md

@@ -2,7 +2,7 @@
 
 The tracking issue for this feature is [#29625]
 
-See Also: [`fn_traits`](library-features/fn-traits.html)
+See Also: [`fn_traits`](../library-features/fn-traits.md)
 
 [#29625]: https://github.com/rust-lang/rust/issues/29625
 

src/doc/unstable-book/src/library-features/fn-traits.md

@@ -2,7 +2,7 @@
 
 The tracking issue for this feature is [#29625]
 
-See Also: [`unboxed_closures`](language-features/unboxed-closures.html)
+See Also: [`unboxed_closures`](../language-features/unboxed-closures.md)
 
 [#29625]: https://github.com/rust-lang/rust/issues/29625
 

src/doc/unstable-book/src/library-features/fnbox.md

@@ -27,6 +27,6 @@ impl<A, F> Fn for &F where F: Fn<A> + ?Sized {}
 
 Before the introduction of [`unsized_locals`][unsized_locals], we had been unable to provide the former impls. That means, unlike `&dyn Fn()` or `&mut dyn FnMut()` we could not use `Box<dyn FnOnce()>` at that time.
 
-[unsized_locals]: language-features/unsized-locals.html
+[unsized_locals]: ../language-features/unsized-locals.md
 
 `FnBox()` is an alternative approach to `Box<dyn FnBox()>` is delegated to `FnBox::call_box` which doesn't need unsized locals. As we now have `Box<dyn FnOnce()>` working, the `fnbox` feature is going to be removed.

src/doc/unstable-book/src/the-unstable-book.md

@@ -14,7 +14,7 @@ fn main() {
 
 The `box_syntax` feature [has a chapter][box] describing how to use it.
 
-[box]: language-features/box-syntax.html
+[box]: language-features/box-syntax.md
 
 Because this documentation relates to unstable features, we make no guarantees
 that what is contained here is accurate or up to date. It's developed on a