Commit graph

145097 commits

Author SHA1 Message Date
Jubilee
c5a3d98cc6
Rollup merge of #119004 - matthiaskrgr:conv, r=compiler-errors
NFC don't convert types to identical types
2023-12-15 21:33:00 -08:00
Matthias Krüger
8479945c08 NFC don't convert types to identical types 2023-12-15 23:56:24 +01:00
Jubilee
58353fa458
Rollup merge of #118727 - compiler-errors:lint-decorate, r=WaffleLapkin
Don't pass lint back out of lint decorator

Change the decorator function in the signature of the `emit_lint`/`span_lint`/etc family of methods from `impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>) -> &'b mut DiagnosticBuilder<'a, ()>` to `impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>)`. I consider it easier to read this way, especially when there's control flow involved.

r? nnethercote though feel free to reassign
2023-12-15 14:08:16 -08:00
Jubilee
1d54949765
Rollup merge of #118396 - compiler-errors:ast-lang-items, r=cjgillot
Collect lang items from AST, get rid of `GenericBound::LangItemTrait`

r? `@cjgillot`
cc #115178

Looking forward, the work to remove `QPath::LangItem` will also be significantly more difficult, but I plan on doing it as well. Specifically, we have to change:
1. A lot of `rustc_ast_lowering` for things like expr `..`
2. A lot of astconv, since we actually instantiate lang and non-lang paths quite differently.
3. A ton of diagnostics and clippy lints that are special-cased via `QPath::LangItem`

Meanwhile, it was pretty easy to remove `GenericBound::LangItemTrait`, so I just did that here.
2023-12-15 14:08:15 -08:00
Matthias Krüger
b377babd2b
Rollup merge of #118986 - GuillaumeGomez:simplify-js-inline, r=notriddle
Simplify JS code a little bit

As mentioned, JS code can be simplified a little bit.

r? ``@notriddle``
2023-12-15 20:19:55 +01:00
Matthias Krüger
ae9e08e65e
Rollup merge of #118977 - GuillaumeGomez:simplifysrc-script, r=notriddle
Simplify `src-script.js` code

Instead of keeping this value in the global scope and still use it in the function in case it wasn't used outside, let's just use it inside the function.

r? ``@notriddle``
2023-12-15 20:19:54 +01:00
Michael Goulet
553c3c44b2 Appease the tools: clippy, rustdoc 2023-12-15 16:17:27 +00:00
Michael Goulet
7f565ed282 Don't pass lint back out of lint decorator 2023-12-15 16:05:36 +00:00
Guillaume Gomez
028a3135c8 Simplify JS code a little bit 2023-12-15 16:56:11 +01:00
bors
4d1bd0db7f Auto merge of #118975 - GuillaumeGomez:rollup-0emhjx0, r=GuillaumeGomez
Rollup of 4 pull requests

Successful merges:

 - #113091 (Don't merge cfg and doc(cfg) attributes for re-exports)
 - #115660 (rustdoc: allow resizing the sidebar / hiding the top bar)
 - #118863 (rustc_mir_build: Enforce `rustc::potential_query_instability` lint)
 - #118909 (Some cleanup and improvement for invalid ref casting impl)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-12-15 12:49:36 +00:00
Guillaume Gomez
552143c875 Simplify src-script.js code 2023-12-15 12:26:09 +01:00
Guillaume Gomez
f8b92697a1
Rollup merge of #115660 - notriddle:notriddle/sidebar-resize, r=GuillaumeGomez
rustdoc: allow resizing the sidebar / hiding the top bar

Fixes #97306

Preview: http://notriddle.com/rustdoc-html-demo-4/sidebar-resize/std/index.html

![image](https://github.com/rust-lang/rust/assets/1593513/a2f40ea2-0436-4e44-99e8-d160dab2a680)

## Summary

This feature adds:

1. A checkbox to the Settings popover to hide the persistent navigation bar (the sidebar on large viewports and the top bar on small ones).
2. On large viewports, it adds a resize handle to the persistent sidebar. Resizing it into nothing is equivalent to turning off the persistent navigation bar checkbox in Settings.
3. If the navigation bar is hidden, a toolbar button to the left of the search appears. Clicking it brings the navigation bar back.

## Motivation

While "mobile mode" is definitely a good default, it's not the only reason people have wanted to hide the sidebar:

* Some people use tiling window managers, and don't like rustdoc's current breakpoints. Changing the breakpoints might help with that, but there's no perfect solution, because there's a gap between "huge screen" and "smartphone" where reasonable people can disagree about whether it makes sense for the sidebar to be on-screen. https://github.com/rust-lang/rust/issues/97306

* Some people ask for ways to reduce on-screen clutter because it makes it easier to focus. There's not a media query for that (and if there was, privacy-conscious users would turn it off). https://github.com/rust-lang/rust/issues/59829

This feature is designed to avoid these problems. Resizing the sidebar especially helps, because it provides a way to hide the sidebar without adding a new top-level button (which would add clutter), and it provides a way to make rustdoc play nicer in complex, custom screen layouts.

## Guide and Reference-level explanation

On a desktop or laptop with a mouse, resize the sidebar by dragging its right edge.

On any browser, including mobile phones, the sticky top bar or side bar can be hidden from the Settings area (the button with the cog wheel, next to the search bar). When it's hidden, a convenient button will appear on the search bar's left.

## Drawbacks

This adds more JavaScript code to the render blocking area.

## Rationale and alternatives

The most obvious way to allow people to hide the sidebar would have been to let them "manually enter mobile mode." The upside is that it's a feature we already have. The downside is that it's actually really hard to come up with a terse description. Is it:

* A Setting that forces desktop viewers to always have the mobile-style top bar? If so, how do we label it? Should it be visible on mobile, and, if so, does it just not do anything?
* A persistent hide/show sidebar button, present on desktop, just like on mobile? That's clutter that I'd like to avoid.

## Prior art

* The new file browser in GitHub uses a similar divider with a mouse-over indicator
* mdBook and macOS Finder both allow you to resize the sidebar to nothing as a gesture to hide it
* https://www.nngroup.com/articles/drag-drop/

## Future possibilities

https://rust-lang.zulipchat.com/#narrow/stream/266220-rustdoc/topic/Table.20of.20contents proposes a new, second sidebar (a table of contents). How should it fit in with this feature? Should it be resizeable? Hideable? Can it be accessed on mobile?
2023-12-15 11:51:23 +01:00
Guillaume Gomez
ec0008a915
Rollup merge of #113091 - GuillaumeGomez:prevent-cfg-merge-reexport, r=rustdoc
Don't merge cfg and doc(cfg) attributes for re-exports

Fixes #112881.

## Explanations

When re-exporting things with different `cfg`s there are two things that can happen:

 * The re-export uses a subset of `cfg`s, this subset is sufficient so that the item will appear exactly with the subset
 * The re-export uses a non-subset of `cfg`s (e.g. like the example I posted just above where the re-export is ungated), if the non-subset `cfg`s are active (e.g. compiling that example on windows) then this will be a compile error as the item doesn't exist to re-export, if the subset `cfg`s are active it behaves like 1.

### Glob re-exports?

**This only applies to non-glob inlined re-exports.** For glob re-exports the item may or may not exist to be re-exported (potentially the `cfg`s on the path up until the glob can be removed, and only `cfg`s on the globbed item itself matter), for non-inlined re-exports see https://github.com/rust-lang/rust/issues/85043.

cc `@Nemo157`
r? `@notriddle`
2023-12-15 11:51:23 +01:00
bors
96df494340 Auto merge of #118961 - notriddle:notriddle/varconst, r=GuillaumeGomez
rustdoc-search: fix a race condition in search index loading

`var` declare it in the global scope, and `const` does not. It needs to be declared in global scope.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/var

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/const

> const declarations do not create properties on [globalThis](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis) when declared at the top level of a script.

Fixes a regression introduced by https://github.com/rust-lang/rust/pull/118910
2023-12-15 10:50:09 +00:00
Matthias Krüger
d5af762fe5
Rollup merge of #118888 - compiler-errors:uplift-more-things, r=jackh726
Uplift `TypeAndMut` and `ClosureKind` to `rustc_type_ir`

Uplifts `TypeAndMut` and `ClosureKind`

I know I said I was just going to get rid of `TypeAndMut` (https://github.com/rust-lang/types-team/issues/124) but I think this is much simpler, lol

r? `@jackh726` or `@lcnr`
2023-12-15 06:50:18 +01:00
Michael Howell
09c8fd35ac rustdoc-search: fix a race condition in search index loading
`var` declare it in the global scope, and `const` does not.
It needs to be declared in global scope.
2023-12-14 20:08:53 -07:00
bors
604f185fae Auto merge of #118936 - nikic:update-llvm-18, r=cuviper
Update to LLVM 17.0.6

This is a rebase on the final LLVM 17 release.

Includes the RISCV fix requested in https://github.com/rust-lang/llvm-project/pull/157 (and I think this is also the only change in this release that is relevant to rustc).

r? `@cuviper`

Fixes #117902
2023-12-15 02:15:55 +00:00
Jubilee
b62511fd9d
Rollup merge of #118943 - lqd:update-deps2, r=michaelwoerister
update `measureme` to 10.1.2 to deduplicate `parking_lot`

This PR updates `measureme` to the latest release to remove the last duplicates of `parking_lot` 0.11 we had in our dependency tree.

```console
Updating measureme v10.1.1 -> v10.1.2
Removing parking_lot v0.11.2
Removing parking_lot_core v0.8.6
```

Also removes `instant` from the allowed list of dependencies, as it's no longer used.

r? `@michaelwoerister` (Thanks for the release in the first place 🙏)
2023-12-14 16:07:48 -08:00
Jubilee
9e872b7cd8
Rollup merge of #118933 - nnethercote:cleanup-errors-even-more, r=compiler-errors
Cleanup errors handlers even more

A sequel to #118587.

r? `@compiler-errors`
2023-12-14 16:07:48 -08:00
Nicholas Nethercote
9a78412511 Split Handler::emit_diagnostic in two.
Currently, `emit_diagnostic` takes `&mut self`.

This commit changes it so `emit_diagnostic` takes `self` and the new
`emit_diagnostic_without_consuming` function takes `&mut self`.

I find the distinction useful. The former case is much more common, and
avoids a bunch of `mut` and `&mut` occurrences. We can also restrict the
latter with `pub(crate)` which is nice.
2023-12-15 10:13:12 +11:00
bors
de686cbc65 Auto merge of #118949 - matthiaskrgr:rollup-rdzlb9h, r=matthiaskrgr
Rollup of 4 pull requests

Successful merges:

 - #118910 ([rustdoc] Use Map instead of Object for source files and search index)
 - #118914 (Unconditionally register alias-relate in projection goal)
 - #118935 (interpret: extend comment on the inhabitedness check in downcast)
 - #118945 (rustc_codegen_ssa: Remove trailing spaces in Display impl for CguReuse)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-12-14 21:20:48 +00:00
Matthias Krüger
9ec620546f
Rollup merge of #118910 - GuillaumeGomez:js-object-to-map, r=notriddle
[rustdoc] Use Map instead of Object for source files and search index

It's cleaner and is also easier to manipulate `Map` rather than `Object` types.

r? `@notriddle`
2023-12-14 20:33:10 +01:00
bors
740cea81d6 Auto merge of #118375 - ouz-a:add_emit_stable_mir_tests, r=celinval
Add -Zunpretty=stable-mir output test

As strongly suggested here https://github.com/rust-lang/rust/pull/118364#issuecomment-1827974148 this adds output test for `-Zunpretty=stable-mir`, added test shows almost all the functionality of the current printer.

r? `@compiler-errors`
2023-12-14 19:17:52 +00:00
Rémy Rakic
05b64a84a3 remove instant from allowed dependencies 2023-12-14 16:05:46 +00:00
bors
2ecba0fa00 Auto merge of #118937 - lcnr:rename-solver-flag, r=compiler-errors
`-Ztrait-solver=next` to `-Znext-solver`

renames the feature flag to enable the new trait solver.

still want some feedback before merging: https://rust-lang.zulipchat.com/#narrow/stream/364551-t-types.2Ftrait-system-refactor/topic/renaming.20the.20feature.20flag.20to.20.60-Znew-solver.60.

The idea is to make it easier to add another option, e.g. to enable the solver in wfcheck or to optionally change its behavior to our new coinduction approach.

r? `@compiler-errors`
2023-12-14 15:29:38 +00:00
ouz-a
82ee18c4ea add stable_mir output test 2023-12-14 18:10:38 +03:00
Nikita Popov
601d52a703 Include an additional cherry-pick 2023-12-14 16:05:39 +01:00
Nikita Popov
5a8d6e784d Fix bootstrap test failures
There are a number of fixes here:
 * if-unchanged is supposed to be the default for channel=dev, but
   actually used different logic. Make sure it is the same.
 * If no llvm section was specified at all, different logic was
   also used. Go through the standard helper.
 * Some more assertions should depend on if_unchanged.
2023-12-14 15:52:47 +01:00
lcnr
11d16c4082 update use of feature flags 2023-12-14 15:22:37 +01:00
bors
529047cfc3 Auto merge of #118789 - jyn514:dry-run, r=onur-ozkan
fix --dry-run when the change-id warning is printed

previously:
```
Building bootstrap
   Compiling bootstrap v0.0.0 (/home/jyn/src/rust2/src/bootstrap)
    Finished dev [unoptimized] target(s) in 4.23s
thread 'main' panicked at src/bin/main.rs:147:17:
fs::write(warned_id_path, latest_change_id.to_string()) failed with No such file or directory (os error 2)
```
2023-12-14 13:30:48 +00:00
Guillaume Gomez
fc7221689e Use Map instead of Object for source files and search index 2023-12-14 13:33:26 +01:00
bors
1aa6aefdc9 Auto merge of #118566 - klensy:cstr-new, r=WaffleLapkin
use c literals in compiler and library

Relands refreshed https://github.com/rust-lang/rust/pull/111647
2023-12-14 11:14:03 +00:00
bors
9d49eb76c4 Auto merge of #118417 - anforowicz:default-hidden-visibility, r=TaKO8Ki
Add unstable `-Zdefault-hidden-visibility` cmdline flag for `rustc`.

The new flag has been described in the Major Change Proposal at
https://github.com/rust-lang/compiler-team/issues/656
2023-12-14 09:16:15 +00:00
Nikita Popov
bb7c483e48 Update to LLVM 17.0.6 2023-12-14 09:54:14 +01:00
bors
1a8afa0e74 Auto merge of #118538 - RalfJung:size-of-val-comments, r=WaffleLapkin
fix dynamic size/align computation logic for packed types with dyn trait tail

This logic was never updated to support `packed(N)` where `N > 1`, and it turns out to be wrong for that case.

Fixes https://github.com/rust-lang/rust/issues/80925

`@bjorn3` I have not looked at cranelift; I assume it basically copied the size-of-val logic and hence could use much the same patch.
2023-12-14 07:19:07 +00:00
bors
d23e1a6894 Auto merge of #117749 - aliemjay:perf-canon-cache, r=lcnr
cache param env canonicalization

Canonicalize ParamEnv only once and store it. Then whenever we try to canonicalize `ParamEnvAnd<'tcx, T>` we only have to canonicalize `T` and then merge the results.

Prelimiary results show ~3-4% savings in diesel and serde benchmarks.

Best to review commits individually. Some commits have a short description.

Initial implementation had a soundness bug (https://github.com/rust-lang/rust/pull/117749#issuecomment-1840453387) due to cache invalidation:
- When canonicalizing `Ty<'?0>` we first try to resolve region variables in the current InferCtxt which may have a constraint `?0 == 'static`. This means that we register `Ty<'?0> => Canonical<Ty<'static>>` in the cache, which is obviously incorrect in another inference context.
- This is fixed by not doing region resolution when canonicalizing the query *input* (vs. response), which is the only place where ParamEnv is used, and then in a later commit we *statically* guard against any form of inference variable resolution of the cached canonical ParamEnv's.

r? `@ghost`
2023-12-14 04:04:10 +00:00
Ali MJ Al-Nasrawy
aa36c35296 rustdoc: avoid ParamEnv with infer vars
ParamEnv's with inference variabels are invalid.
2023-12-14 03:03:03 +00:00
bors
eeff92ad32 Auto merge of #118402 - notriddle:notriddle/ranking-and-filtering, r=GuillaumeGomez
rustdoc-search: use set ops for ranking and filtering

This commit adds ranking and quick filtering to type-based search, improving performance and having it order results based on their type signatures.

Preview
-------

Profiler output: https://notriddle.com/rustdoc-html-demo-6/profile-8/index.html

Preview: https://notriddle.com/rustdoc-html-demo-6/ranking-and-filtering-v2/std/index.html

Motivation
----------

If I write a query like `str -> String`, a lot of functions come up. That's to be expected, but `String::from` should come up on top, and it doesn't right now. This is because the sorting algorithm is based on the functions name, and doesn't consider the type signature at all. `slice::join` even comes up above it!

To fix this, the sorting should take into account the function's signature, and the closer match should come up on top.

Guide-level description
-----------------------

When searching by type signature, types with a "closer" match will show up above types that match less precisely.

Reference-level explanation
---------------------------

Functions signature search works in three major phases:

* A compact "fingerprint," based on the [bloom filter] technique, is used to check for matches and to estimate the distance. It sometimes has false positive matches, but it also operates on 128 bit contiguous memory and requires no backtracking, so it performs a lot better than real unification.

  The fingerprint represents the set of items in the type signature, but it does not represent nesting, and it ignores when the same item appears more than once.

  The result is rejected if any query bits are absent in the function, or if the distance is higher than the current maximum and 200 results have already been found.

* The second step performs unification. This is where nesting and true bag semantics are taken into account, and it has no false positives. It uses a recursive, backtracking algorithm.

  The result is rejected if any query elements are absent in the function.

[bloom filter]: https://en.wikipedia.org/wiki/Bloom_filter

Drawbacks
---------

This makes the code bigger.

More than that, this design is a subtle trade-off. It makes the cases I've tested against measurably faster, but it's not clear how well this extends to other crates with potentially more functions and fewer types.

The more complex things get, the more important it is to gather a good set of data to test with (this is arguably more important than the actual benchmarking ifrastructure right now).

Rationale and alternatives
--------------------------

Throwing a bloom filter in front makes it faster.

More than that, it tries to take a tactic where the system can not only check for potential matches, but also gets an accurate distance function without needing to do unification. That way it can skip unification even on items that have the needed elems, as long as they have more items than the currently found maximum.

If I didn't want to be able to cheaply do set operations on the fingerprint, a [cuckoo filter] is supposed to have better performance. But the nice bit-banging set intersection doesn't work AFAIK.

I also looked into [minhashing], but since it's actually an unbiased estimate of the similarity coefficient, I'm not sure how it could be used to skip unification (I wouldn't know if the estimate was too low or too high).

This function actually uses the number of distinct items as its "distance function." This should give the same results that it would have gotten from a Jaccard Distance $1-\frac{|F\cap{}Q|}{|F\cup{}Q|}$, while being cheaper to compute. This is because:

* The function $F$ must be a superset of the query $Q$, so their union is just $F$ and the intersection is $Q$ and it can be reduced to $1-\frac{|Q|}{|F|}.

* There are no magic thresholds. These values are only being used to compare against each other while sorting (and, if 200 results are found, to compare with the maximum match). This means we only care if one value is bigger than the other, not what it's actual value is, and since $Q$ is the same for everything, it can be safely left out, reducing the formula to $1-\frac{1}{|F|} = \frac{|F|}{|F|}-\frac{1}{|F|} = |F|-1$. And, since the values are only being compared with each other, $|F|$ is fine.

Prior art
---------

This is significantly different from how Hoogle does it.
It doesn't account for order, and it has no special account for nesting, though `Box<t>` is still two items, while `t` is only one.

This should give the same results that it would have gotten from a Jaccard Distance $1-\frac{|A\cap{}B|}{|A\cup{}B|}$, while being cheaper to compute.

Unresolved questions
--------------------

`[]` and `()`, the slice/array and tuple/union operators, are ignored while building the signature for the query. This is because they match more than one thing, making them ambiguous. Unfortunately, this also makes them a performance cliff. Is this likely to be a problem?

Right now, the system just stashes the type distance into the same field that levenshtein distance normally goes in. This means exact query matches show up on top (for example, if you have a function like `fn nothing(a: Nothing, b: i32)`, then searching for `nothing` will show it on top even if there's another function with `fn bar(x: Nothing)` that's technically a closer match in type signature.

Future possibilities
--------------------

It should be possible to adopt more sorting criteria to act as a tie breaker, which could be determined during unification.

[cuckoo filter]: https://en.wikipedia.org/wiki/Cuckoo_filter
[minhashing]: https://en.wikipedia.org/wiki/MinHash
2023-12-13 21:45:01 +00:00
Lukasz Anforowicz
981c4e3ce6 Add unstable -Zdefault-hidden-visibility cmdline flag for rustc.
The new flag has been described in the Major Change Proposal at
https://github.com/rust-lang/compiler-team/issues/656
2023-12-13 21:14:23 +00:00
Ralf Jung
7e4c4271f4 fix computing the dynamic alignment of packed structs with dyn trait tails 2023-12-13 20:21:57 +01:00
bors
2862500152 Auto merge of #118919 - matthiaskrgr:rollup-02udckl, r=matthiaskrgr
Rollup of 4 pull requests

Successful merges:

 - #118759 (Support bare unit structs in destructuring assignments)
 - #118871 (Coroutine variant fields can be uninitialized)
 - #118883 (Change a typo mistake in the-doc-attribute.md)
 - #118906 (Fix LLD thread flags in bootstrap on Windows)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-12-13 17:45:17 +00:00
Michael Howell
bec6672984 rustdoc-search: clean up handleSingleArg type handling 2023-12-13 10:37:52 -07:00
Michael Howell
9dfcf131b3 rustdoc-search: better hashing, faster unification
The hash changes are based on some tests with `arti` and various
specific queries, aimed at reducing the false positive rate.

Sorting the query elements so that generics always come first is
instead aimed at reducing the number of Map operations on mgens,
assuming if the bloom filter does find a false positive, it'll
be able to reject the row without having to track a mapping.

- https://hur.st/bloomfilter/?n=3&p=&m=96&k=6

  Different functions have different amounts of inputs, and
  unification isn't very slow anyway, so figuring out a single
  ideal number of hash functions is nasty, but 6 keeps things
  low even up to 10 inputs.

- https://web.archive.org/web/20210927123933/https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.72.2442&rep=rep1&type=pdf

  This is the `h1` and `h2`, both derived from `h0`.
2023-12-13 10:37:51 -07:00
Michael Howell
9a9695a052 rustdoc-search: use set ops for ranking and filtering
This commit adds ranking and quick filtering to type-based search,
improving performance and having it order results based on their
type signatures.

Motivation
----------

If I write a query like `str -> String`, a lot of functions come up.
That's to be expected, but `String::from_str` should come up on top, and
it doesn't right now. This is because the sorting algorithm is based
on the functions name, and doesn't consider the type signature at all.
`slice::join` even comes up above it!

To fix this, the sorting should take into account the function's
signature, and the closer match should come up on top.

Guide-level description
-----------------------

When searching by type signature, types with a "closer" match will
show up above types that match less precisely.

Reference-level explanation
---------------------------

Functions signature search works in three major phases:

* A compact "fingerprint," based on the [bloom filter] technique, is used to
  check for matches and to estimate the distance. It sometimes has false
  positive matches, but it also operates on 128 bit contiguous memory and
  requires no backtracking, so it performs a lot better than real
  unification.

  The fingerprint represents the set of items in the type signature, but it
  does not represent nesting, and it ignores when the same item appears more
  than once.

  The result is rejected if any query bits are absent in the function, or
  if the distance is higher than the current maximum and 200
  results have already been found.

* The second step performs unification. This is where nesting and true bag
  semantics are taken into account, and it has no false positives. It uses a
  recursive, backtracking algorithm.

  The result is rejected if any query elements are absent in the function.

[bloom filter]: https://en.wikipedia.org/wiki/Bloom_filter

Drawbacks
---------

This makes the code bigger.

More than that, this design is a subtle trade-off. It makes the cases I've
tested against measurably faster, but it's not clear how well this extends
to other crates with potentially more functions and fewer types.

The more complex things get, the more important it is to gather a good set
of data to test with (this is arguably more important than the actual
benchmarking ifrastructure right now).

Rationale and alternatives
--------------------------

Throwing a bloom filter in front makes it faster.

More than that, it tries to take a tactic where the system can not only check
for potential matches, but also gets an accurate distance function without
needing to do unification. That way it can skip unification even on items
that have the needed elems, as long as they have more items than the
currently found maximum.

If I didn't want to be able to cheaply do set operations on the fingerprint,
a [cuckoo filter] is supposed to have better performance.
But the nice bit-banging set intersection doesn't work AFAIK.

I also looked into [minhashing], but since it's actually an unbiased
estimate of the similarity coefficient, I'm not sure how it could be used
to skip unification (I wouldn't know if the estimate was too low or
too high).

This function actually uses the number of distinct items as its
"distance function."
This should give the same results that it would have gotten from a Jaccard
Distance $1-\frac{|F\cap{}Q|}{|F\cup{}Q|}$, while being cheaper to compute.
This is because:

* The function $F$ must be a superset of the query $Q$, so their union is
  just $F$ and the intersection is $Q$ and it can be reduced to
  $1-\frac{|Q|}{|F|}.

* There are no magic thresholds. These values are only being used to
  compare against each other while sorting (and, if 200 results are found,
  to compare with the maximum match). This means we only care if one value
  is bigger than the other, not what it's actual value is, and since $Q$ is
  the same for everything, it can be safely left out, reducing the formula
  to $1-\frac{1}{|F|} = \frac{|F|}{|F|}-\frac{1}{|F|} = |F|-1$. And, since
  the values are only being compared with each other, $|F|$ is fine.

Prior art
---------

This is significantly different from how Hoogle does it.
It doesn't account for order, and it has no special account for nesting,
though `Box<t>` is still two items, while `t` is only one.

This should give the same results that it would have gotten from a Jaccard
Distance $1-\frac{|A\cap{}B|}{|A\cup{}B|}$, while being cheaper to compute.

Unresolved questions
--------------------

`[]` and `()`, the slice/array and tuple/union operators, are ignored while
building the signature for the query. This is because they match more than
one thing, making them ambiguous. Unfortunately, this also makes them
a performance cliff. Is this likely to be a problem?

Right now, the system just stashes the type distance into the
same field that levenshtein distance normally goes in. This means exact
query matches show up on top (for example, if you have a function like
`fn nothing(a: Nothing, b: i32)`, then searching for `nothing` will show it
on top even if there's another function with `fn bar(x: Nothing)` that's
technically a closer match in type signature.

Future possibilities
--------------------

It should be possible to adopt more sorting criteria to act as a tie breaker,
which could be determined during unification.

[cuckoo filter]: https://en.wikipedia.org/wiki/Cuckoo_filter
[minhashing]: https://en.wikipedia.org/wiki/MinHash
2023-12-13 10:37:15 -07:00
Michael Howell
fd1d256d61 rustdoc-search: remove the now-redundant validateResult
This function dates back to 9a45c9d7c6 and
seems to have been made obsolete when `addIntoResult` grew the ability to
check the levenshtein distance matching with commit
ba824ec52b.
2023-12-13 10:35:36 -07:00
Matthias Krüger
251d1af0d2
Rollup merge of #118906 - Kobzol:bootstrap-is-windows, r=petrochenkov
Fix LLD thread flags in bootstrap on Windows

Fixes [this comment](https://github.com/rust-lang/rust/pull/116278#discussion_r1424627056).

r? `@petrochenkov`
2023-12-13 18:03:34 +01:00
Matthias Krüger
666353e7ba
Rollup merge of #118883 - HosseinAssaran:patch-1, r=fmease
Change a typo mistake in the-doc-attribute.md

I guess that `Bar` in the section I changed should be `bar` because when I run the program it has its page under struct but bar doesn't have any page.
2023-12-13 18:03:34 +01:00
bors
7176b8babd Auto merge of #118894 - dtolnay:bootstrapwrite, r=onur-ozkan
Unbreak non-unix non-windows bootstrap

Fixes #118862.

#118647 added a new use of std::io::Write that is not conditional on any cfg.

028b6d152e/src/bootstrap/src/bin/main.rs (L134)

```console
error[E0599]: no method named `write_all` found for struct `File` in the current scope
   --> src/bin/main.rs:134:21
    |
134 |             t!(file.write_all(lines.join("\n").as_bytes()));
    |                     ^^^^^^^^^ method not found in `File`
    |
    = help: items from traits can only be used if the trait is in scope
help: the following trait is implemented but not in scope; perhaps add a `use` for it:
    |
8   + use std::io::Write;
    |
```
2023-12-13 15:17:26 +00:00
bors
56d25ba5ea Auto merge of #118500 - ZetaNumbers:tcx_hir_refactor, r=petrochenkov
Move some methods from `tcx.hir()` to `tcx`

https://github.com/rust-lang/rust/pull/118256#issuecomment-1826442834

Renamed:
- find -> opt_hir_node
- get -> hir_node
- find_by_def_id -> opt_hir_node_by_def_id
- get_by_def_id -> hir_node_by_def_id
2023-12-13 10:31:56 +00:00
bors
2fdd9eda0c Auto merge of #118534 - RalfJung:extern-type-size-of-val, r=WaffleLapkin
codegen: panic when trying to compute size/align of extern type

The alignment is also computed when accessing a field of extern type at non-zero offset, so we also panic in that case.

Previously `size_of_val` worked because the code path there assumed that "thin pointer" means "sized". But that's not true any more with extern types. The returned size and align are just blatantly wrong, so it seems better to panic than returning wrong results. We use a non-unwinding panic since code probably does not expect size_of_val to panic.
2023-12-13 08:33:05 +00:00