rustdoc: auto create output directory when "--output-format json"
This PR allows rustdoc to automatically create output directory in case it does not exist (when run with `--output-format json`).
This fixes rustdoc crash:
````
$ rustdoc --output-format json -Z unstable-options src/main.rs
error: couldn't generate documentation: No such file or directory (os error 2)
|
= note: failed to create or modify "doc/main.json"
error: aborting due to previous error
````
With this fix behavior of `rustdoc --output-format json` becomes consistent with `rustdoc --output-format html` (which already auto-creates output directory if it's missing)
Show a more informative panic message when `DefPathHash` does not exist
This should hopefully make it easier to debug incremental compilation
bugs like #93096 without affecting performance.
src/test/rustdoc-json: Check for `struct_field`s in `variant_tuple_struct.rs`
The presence of `struct_field`s is being checked for already in
`variant_struct.rs`. We should also check for them in `variant_tuple_struct.rs`.
This PR is one small step towards resolving #92945.
Fix src/test/run-make/raw-dylib-alt-calling-convention
Fix the test headers so that the test now runs on all intended platforms; it is currently ignored on all platforms because the headers are incorrect. Also comment out a couple of function calls that fail because of an unrelated problem, described in issue #91167.
Add tests to ensure that `let_chains` works with `if_let_guard`
The current machinery already makes such combination possible but lacks tests.
cc `@matthewjasper`
rustdoc mobile: fix scroll offset when jumping to internal id
Followup to #92692. The semantics of `scroll-margin-top` are a little surprising - the attribute needs to be applied to the element that gets scrolled into the viewport, not the scrolling element.
This fixes an issue where clicking on a method (or other item) from the sidebar takes you to a scroll position where the topbar covers up the method name.
I'm interested in ideas for how to test this with browser-ui-test, but I think it doesn't yet have what I need. What I need is an assert that `<element>.getBoundingClientRect().y` is > 45.
Demo: https://rustdoc.crud.net/jsha/fix-scroll-padding-top/std/string/struct.String.html#method.extend_from_within
r? `@GuillaumeGomez`
Fix star handling in block doc comments
Fixes#92872.
Some extra explanation about this PR and why https://github.com/rust-lang/rust/pull/92357 created this regression: when we merge doc comment kinds for example in:
```rust
/// he
/**
* hello
*/
#[doc = "boom"]
```
We don't want to remove the empty lines between them. However, to correctly compute the "horizontal trim", we still need it, so instead, I put back a part of the "vertical trim" directly in the "horizontal trim" computation so it doesn't impact the output buffer but allows us to correctly handle the stars.
r? ``@camelid``
Fix errors on blanket impls by ignoring the children of generated impls
Related to #83718
We can safely skip the children, as they don't contain any new info, and may be subtly different for reasons hard to track down, in ways that are consistently worse than the actual generic impl.
Introduce drop range tracking to generator interior analysis
This PR addresses cases such as this one from #57478:
```rust
struct Foo;
impl !Send for Foo {}
let _: impl Send = || {
let guard = Foo;
drop(guard);
yield;
};
```
Previously, the `generator_interior` pass would unnecessarily include the type `Foo` in the generator because it was not aware of the behavior of `drop`. We fix this issue by introducing a drop range analysis that finds portions of the code where a value is guaranteed to be dropped. If a value is dropped at all suspend points, then it is no longer included in the generator type. Note that we are using "dropped" in a generic sense to include any case in which a value has been moved. That is, we do not only look at calls to the `drop` function.
There are several phases to the drop tracking algorithm, and we'll go into more detail below.
1. Use `ExprUseVisitor` to find values that are consumed and borrowed.
2. `DropRangeVisitor` uses consume and borrow information to gather drop and reinitialization events, as well as build a control flow graph.
3. We then propagate drop and reinitialization information through the CFG until we reach a fix point (see `DropRanges::propagate_to_fixpoint`).
4. When recording a type (see `InteriorVisitor::record`), we check the computed drop ranges to see if that value is definitely dropped at the suspend point. If so, we skip including it in the type.
## 1. Use `ExprUseVisitor` to find values that are consumed and borrowed.
We use `ExprUseVisitor` to identify the places where values are consumed. We track both the `hir_id` of the value, and the `hir_id` of the expression that consumes it. For example, in the expression `[Foo]`, the `Foo` is consumed by the array expression, so after the array expression we can consider the `Foo` temporary to be dropped.
In this process, we also collect values that are borrowed. The reason is that the MIR transform for generators conservatively assumes anything borrowed is live across a suspend point (see `rustc_mir_transform::generator::locals_live_across_suspend_points`). We match this behavior here as well.
## 2. Gather drop events, reinitialization events, and control flow graph
After finding the values of interest, we perform a post-order traversal over the HIR tree to find the points where these values are dropped or reinitialized. We use the post-order index of each event because this is how the existing generator interior analysis refers to the position of suspend points and the scopes of variables.
During this traversal, we also record branching and merging information to handle control flow constructs such as `if`, `match`, and `loop`. This is necessary because values may be dropped along some control flow paths but not others.
## 3. Iterate to fixed point
The previous pass found the interesting events and locations, but now we need to find the actual ranges where things are dropped. Upon entry, we have a list of nodes ordered by their position in the post-order traversal. Each node has a set of successors. For each node we additionally keep a bitfield with one bit per potentially consumed value. The bit is set if we the value is dropped along all paths entering this node.
To compute the drop information, we first reverse the successor edges to find each node's predecessors. Then we iterate through each node, and for each node we set its dropped value bitfield to the intersection of all incoming dropped value bitfields.
If any bitfield for any node changes, we re-run the propagation loop again.
## 4. Ignore dropped values across suspend points
At this point we have a data structure where we can ask whether a value is guaranteed to be dropped at any post order index for the HIR tree. We use this information in `InteriorVisitor` to check whether a value in question is dropped at a particular suspend point. If it is, we do not include that value's type in the generator type.
Note that we had to augment the region scope tree to include all yields in scope, rather than just the last one as we did before.
r? `@nikomatsakis`
This PR allows rustdoc to automatically create output directory in case
it does not exist (when run with `--output-format json`).
This fixes rustdoc crash:
````
$ rustdoc --output-format json -Z unstable-options src/main.rs
error: couldn't generate documentation: No such file or directory (os error 2)
|
= note: failed to create or modify "doc/main.json"
error: aborting due to previous error
````
With this fix behavior of `rustdoc --output-format json` becomes consistent
with `rustdoc --output-format html` (which already auto-creates output
directory if it's missing)
Pretty printer algorithm revamp step 2
This PR follows #92923 as a second chunk of modernizations backported from https://github.com/dtolnay/prettyplease into rustc_ast_pretty.
I've broken this up into atomic commits that hopefully are sensible in isolation. At every commit, the pretty printer is compilable and has runtime behavior that is identical to before and after the PR. None of the refactoring so far changes behavior.
The general theme of this chunk of commits is: the logic in the old pretty printer is doing some very basic things (pushing and popping tokens on a ring buffer) but expressed in a too-low-level way that I found makes it quite complicated/subtle to reason about. There are a number of obvious invariants that are "almost true" -- things like `self.left == self.buf.offset` and `self.right == self.buf.offset + self.buf.data.len()` and `self.right_total == self.left_total + self.buf.data.sum()`. The reason these things are "almost true" is the implementation tends to put updating one side of the invariant unreasonably far apart from updating the other side, leaving the invariant broken while unrelated stuff happens in between. The following code from master is an example of this:
e5e2b0be26/compiler/rustc_ast_pretty/src/pp.rs (L314-L317)
In this code the `advance_right` is reserving an entry into which to write a next token on the right side of the ring buffer, the `check_stack` is doing something totally unrelated to the right boundary of the ring buffer, and the `scan_push` is actually writing the token we previously reserved space for. Much of what this PR is doing is rearranging code to shrink the amount of stuff in between when an invariant is broken to when it is restored, until the whole thing can be factored out into one indivisible method call on the RingBuffer type.
The end state of the PR is that we can entirely eliminate `self.left` (because it's now just equal to `self.buf.offset` always) and `self.right` (because it's equal to `self.buf.offset + self.buf.data.len()` always) and the whole `Token::Eof` state which used to be the value of tokens that have been reserved space for but not yet written.
I found without these changes the pretty printer implementation to be hard to reason about and I wasn't able to confidently introduce improvements like trailing commas in `prettyplease` until after this refactor. The logic here is 43 years old at this point (Graydon translated it as directly as possible from the 1979 pretty printing paper) and while there are advantages to following the paper as closely as possible, in `prettyplease` I decided if we're going to adapt the algorithm to work better for Rust syntax, it was worthwhile making it easier to follow than the original.
Add manifest docs fallback.
This adds a fallback so that the rustup manifest will contain the rust-docs component for all hosts. There is a mapping so that the docs that get downloaded are roughly close to the actual host. There inevitably will be things that don't match. Ideally the standard library docs would be the same for every platform (`cfg(doc)` goes a long way towards this), but there are still lots of minor differences.
Closes#69525
Change PhantomData type for `BuildHasherDefault` (and more)
Changes `PhantomData<H>` to `PhantomData<fn() -> H>` for `BuildHasherDefault`. This preserves the covariance of `H`, while it lifts the currently inferred unnecessary bounds like [`H: Send` for `BuildHasherDefault<H>: Send`](https://doc.rust-lang.org/1.57.0/std/hash/struct.BuildHasherDefault.html#impl-Send), etc.
_Edit:_ Also does a similar change for `iter::Empty` and `future::Pending`.
mangling_v0: Skip extern blocks during mangling
There's no need to include the dummy `Nt` into the symbol name, items in extern blocks belong to their parent modules for all purposes except for inheriting the ABI and attributes.
Follow up to https://github.com/rust-lang/rust/pull/92032
(There's also a drive-by fix to the `rust-demangler` tool's tests, which don't run on CI, I initially attempted using them for testing this PR.)
Rollup of 10 pull requests
Successful merges:
- #88642 (Formally implement let chains)
- #89621 (doc: guarantee call order for sort_by_cached_key)
- #91278 (Use iterator instead of recursion in `codegen_place`)
- #92124 (Little improves in CString `new` when creating from slice)
- #92783 (Annotate dead code lint with notes about ignored derived impls)
- #92797 (Remove horizontal lines at top of page)
- #92920 (Move expr- and item-related pretty printing functions to modules)
- #93041 (Remove some unused ordering derivations based on `DefId`)
- #93051 (Add Option::is_some_with and Result::is_{ok,err}_with)
- #93062 (Update books)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Update books
## nomicon
1 commits in c05c452b36358821bf4122f9c418674edd1d713d..66d097d3d80e8f88c288c6879c7c2b909ecf8ad4
2021-12-13 15:23:48 +0900 to 2022-01-05 05:45:21 +0900
- Fix typo / type error in FFI code example (rust-lang/nomicon#327)
## reference
8 commits in f8ba2f12df60ee19b96de24ae5b73af3de8a446b..4dee6eb63d728ffb9e7a2ed443e9ada9275c69d2
2022-01-03 11:02:08 -0800 to 2022-01-18 09:26:33 -0800
- (minor) Remove Expression Path sub-types splits in Pattern specs (rust-lang/reference#1138)
- Document destructuring assignment (rust-lang/reference#1116)
- Document the 2021 edition changes to macros-by-example `pat` metavariables (rust-lang/reference#1135)
- Improve the documentation of macros-by-example metavariable names (rust-lang/reference#1130)
- trait-bounds.md: add pronoun 'that' (rust-lang/reference#1131)
- Say that macros-by-example `ident` metavariables can match raw identifiers (rust-lang/reference#1133)
- State in the UAX31 profile description that a lone `_` is not an identifier (rust-lang/reference#1129)
- Document syntax reserved in Rust 2021 (rust-lang/reference#1128)
## book
17 commits in d3740fb7aad0ea4a80ae20f64dee3a8cfc0c5c3c..f17df27fc14696912c48b8b7a7a8fa49e648088d
2022-01-03 21:46:04 -0500 to 2022-01-18 17:46:28 -0500
- Add a notice to the top of all nostarch snapshots
- Fix quotes
- Grammar (minor): 'or' → 'and' for enum variants
- Propagate edits of chapter 8 to src
- Replies to nostarch edits
- more edits
- ch8 from nostarch
- Fix grammar and line wrapping
- Merge remote-tracking branch 'origin/pr/2880'
- Remove wikipedia link
- Merge remote-tracking branch 'origin/pr/2927'
- Snapshot of ch14 for nostarch
- Backport fixes to chapter 14 noticed while doing nostarch snapshot
- Fix usage of find piped into xargs
- Adjust some more line numbers of Cargo.toml includes
- Merge branch '2909'
- Merge remote-tracking branch 'parkerziegler/fix/ch14-add-one-naming'
## rustc-dev-guide
7 commits in 875464457c4104686faf667f47848aa7b0f0a744..78dd6a4684cf8d6b72275fab6d0429ea40b66338
2021-12-28 22:17:49 -0600 to 2022-01-18 14:44:26 -0300
- Reorganize and expand the testing chapters. (rust-lang/rustc-dev-guide#1281)
- Add inline assembly internals (rust-lang/rustc-dev-guide#1266)
- Spelling: Rename `rust` to `Rust` (rust-lang/rustc-dev-guide#1288)
- Clean up section about FCPs (rust-lang/rustc-dev-guide#1287)
- Address more review comments in rust-lang/rustc-dev-guide#1286.
- Address review comments in rust-lang/rustc-dev-guide#1286.
- Streamline "Getting Started" some more.
Remove some unused ordering derivations based on `DefId`
Like #93018, this removes some unused/unneeded ordering derivations as part of ongoing work on #90317. Here, these changes are aimed at making https://github.com/rust-lang/rust/pull/90749 easier to review, test, and merge.
r? `@cjgillot`
Move expr- and item-related pretty printing functions to modules
Currently *compiler/rustc_ast_pretty/src/pprust/state.rs* is 2976 lines on master. The `tidy` limit is 3000, which is blocking #92243.
This PR adds a `mod expr;` and `mod item;` to move logic related to those AST nodes out of the single huge file.
Little improves in CString `new` when creating from slice
Old code already contain optimization for cases with `&str` and `&[u8]` args. This commit adds a specialization for `&mut[u8]` too.
Also, I added usage of old slice in search for zero bytes instead of new buffer because it produce better code for constant inputs on Windows LTO builds. For other platforms, this wouldn't cause any difference because it calls `libc` anyway.
Inlined `_new` method into spec trait to reduce amount of code generated to `CString::new` callers.
Use iterator instead of recursion in `codegen_place`
This PR fixes the FIXME in `codegen_place` about using iterator instead of recursion when processing the `projection` field in `mir::PlaceRef`. At the same time, it also reduces the right drift.
doc: guarantee call order for sort_by_cached_key
`slice::sort_by_cached_key` takes a caching function `f: impl FnMut(&T) -> K`, which means that the order that calls to the caching function are made is user-visible. This adds a clause to the documentation to promise the current behavior, which is that `f` is called on all elements of the slice from left to right, unless the slice has len < 2 in which case `f` is not called.
For example, this can be used to ensure that the following code is a correct way to involve the index of the element in the sort key:
```rust
let mut index = 0;
slice.sort_by_cached_key(|x| (my_key(index, x), index += 1).0);
```
Formally implement let chains
## Let chains
My longest and hardest contribution since #64010.
Thanks to `@Centril` for creating the RFC and special thanks to `@matthewjasper` for helping me since the beginning of this journey. In fact, `@matthewjasper` did much of the complicated MIR stuff so it's true to say that this feature wouldn't be possible without him. Thanks again `@matthewjasper!`
With the changes proposed in this PR, it will be possible to chain let expressions along side local variable declarations or ordinary conditional expressions. In other words, do much of what the `if_chain` crate already does.
## Other considerations
* `if let guard` and `let ... else` features need special care and should be handled in a following PR.
* Irrefutable patterns are allowed within a let chain context
* ~~Three Clippy lints were already converted to start dogfooding and help detect possible corner cases~~
cc #53667
