Make left column of rustdoc search results narrower
To make more room for the description of the item
The description often has useful text that helps disambiguate between search results, but very little of it is shown.
As a side effect, this breaks the alignment between the search results and the "In Return Types" tab, which tends to line up above the description-- up until I started investigating this, I thought "In Names"/"In Parameters"/"In Return Types" were column headers and I just never saw search results that had info for the "In Parameters" middle column! Now, with the two columns of search results each taking up about a half, they look more like tabs than column headers.
Types that are long still wrap and look good-- I made some artificially long types in the following screenshots.
Before screenshot:
<img width="1258" alt="screen shot 2018-08-03 at 8 32 35 pm" src="https://user-images.githubusercontent.com/193874/43670805-56e3b3b4-975e-11e8-9296-600837d03de2.png">
After screenshot:
<img width="1239" alt="screen shot 2018-08-03 at 8 31 17 pm" src="https://user-images.githubusercontent.com/193874/43670810-6591f9ac-975e-11e8-9e12-4ea9ab1e5806.png">
By adding empty `after` content that clears and is `display: block`.
Technique found here: https://stackoverflow.com/a/7817313/51683
Now any part of a documentation search result that is highlighted when
you hover over it should also be clickable.
Parsing the code block's LangString (```foo) previously checked itself
to see if we were on nightly; that isn't the right place to do so. Move
that check slightly outwards to better abstract LangString.
(This is also an optimization as we avoid the costly environment
variable load of RUSTC_BOOTSTRAP).
[NLL] Fix some things for bootstrap
Some changes that are required when bootstrapping rustc with NLL enabled.
* Remove a bunch of unused `mut`s that aren't needed, but the existing lint doesn't catch.
* Rewrite a function call to satisfy NLL borrowck. Note that the borrow is two-phase, but gets activated immediately by an unsizing coercion.
cc #51823
Don't format!() string literals
Prefer `to_string()` to `format!()` take 2, this time targetting string literals. In some cases (`&format!("...")` -> `"..."`) also removes allocations. Occurences of `format!("")` are changed to `String::new()`.
Replace push loops with extend() where possible
Or set the vector capacity where I couldn't do it.
According to my [simple benchmark](https://gist.github.com/ljedrz/568e97621b749849684c1da71c27dceb) `extend`ing a vector can be over **10 times** faster than `push`ing to it in a loop:
10 elements (6.1 times faster):
```
test bench_extension ... bench: 75 ns/iter (+/- 23)
test bench_push_loop ... bench: 458 ns/iter (+/- 142)
```
100 elements (11.12 times faster):
```
test bench_extension ... bench: 87 ns/iter (+/- 26)
test bench_push_loop ... bench: 968 ns/iter (+/- 3,528)
```
1000 elements (11.04 times faster):
```
test bench_extension ... bench: 311 ns/iter (+/- 9)
test bench_push_loop ... bench: 3,436 ns/iter (+/- 233)
```
Seems like a good idea to use `extend` as much as possible.
rustdoc: rework how default passes are chosen
This is a refactor that changes how we select default passes, and changes the set of passes used for `--document-private-items`. It's groundwork for a bigger refactor i want to do.
The major changes:
* There are now two sets of "default passes": one set for "no flags given" and one for "document private items".
* These sets can be selected by a new `DefaultPassOption` enum, which is selected from based on the presence of `--no-defaults` or `--document-private-items` CLI flags, or their associated crate attributes.
* When printing the list of passes, we also print the list of passes for `--document-private-items` in addition to the "default defaults".
* I added `propagate-doc-cfg` and `strip-priv-imports` to the "document private items" set. The former is to ensure items are properly tagged with the full set of cfg flags even when "document private items" is active. The latter is based on feedback and personal experience navigating the `rustc` docs, which use that flag. `strip-priv-imports` only removes non-pub `use` statements, so it should be harmless from a documentation standpoint to remove those items from "private items" documentation.
