Rollup merge of #44989 - QuietMisdreavus:what-is-your-quest, r=GuillaumeGomez

let rustdoc print the crate version into docs

This PR adds a new unstable flag to rustdoc, `--crate-version`, which when present will add a new entry to the sidebar of the root module, printing the given version number:

![Screenshot of a test crate, showing "Version 1.3.37" under the crate name](https://user-images.githubusercontent.com/5217170/31104096-805e3f4c-a7a0-11e7-96fc-368b6fe063d6.png)

Closes #24336

(The WIP status is because i don't want to merge this until i can get the std docs to use it, which i need help from rustbuild people to make sure i get right.)

1 files changed, 13 insertions, 0 deletions

diff --git a/src/test/rustdoc/crate-version.rs b/src/test/rustdoc/crate-version.rs
new file mode 100644
index 00000000000..07ab5ceedfa
--- /dev/null
+++ b/src/test/rustdoc/crate-version.rs
@@ -0,0 +1,13 @@
+// Copyright 2016 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.
+
+// compile-flags: --crate-version=1.3.37 -Z unstable-options
+
+// @has 'crate_version/index.html' '//div[@class="block version"]/p' 'Version 1.3.37'