Add Result<Result<T, E>, E>::flatten -> Result<T, E>
This PR makes this possible (modulo type inference):
```rust
assert_eq!(Ok(6), Ok(Ok(6)).flatten());
```
Tracking issue: #70142
<sub>largely cribbed directly from <https://github.com/rust-lang/rust/pull/60256></sub>
BTreeMap testing: introduce symbolic constants and use height consistently
Doesn't change what or how much is tested, except for some exact integer types, just for convenience and because `node::CAPACITY` is a usize.
r? @RalfJung
This diff improves error messages around raw strings in a few ways:
- Catch extra trailing `#` in the parser. This can't be handled in the lexer because we could be in a macro that actually expects another # (see test)
- Refactor & unify error handling in the lexer between ByteStrings and RawByteStrings
- Detect potentially intended terminators (longest sequence of "#*" is suggested)
rename Scalar::{ptr_null -> null_ptr} and add "machine_" prefix like elsewhere
"NULL pointer" is just much more common terminology than "pointer-null".
Also I forgot two methods when renaming all the `Scalar` things to `(to|from)_machine_(u|i)size`.
ASCII methods on OsStr
Would close#69566
I don't know enough about encodings to know if this is a valid change, however the comment on the issue suggests it could be.
This does two things:
1. Makes ASCII methods available on OsStr
2. Makes it possible to obtain a `&mut OsStr`. This is necessary to actually use `OsStr::make_ascii_*case` methods since they modify the underlying value. As far as I can tell, the only way to modify a `&mut OsStr` is via the methods I just added.
My original hope was to have these methods on `OsStrExt` for Windows, since the standard library already assumes `make_ascii_uppercase` is valid in Windows (see the change I made to windows/process.rs). If it is found these are not valid changes on non-Windows platforms, I can move the methods to the ext trait instead.
Replace last mention of IRC with Discord
Mozilla's IRC service was shut down in March 2020. The official instant messaging variant has been Discord for a while, and most of the links were already replaced by #61524.
This was the last line that came up with `irc.mozilla.org` or any combination of "irc.*#[a-z]+" in a `git grep`:
git grep -i -E "irc.*#[a-z]+"
As there is only one other link directly to Rust's discord, I used the same Markdown link `[rust-discord]` as in `bootstrap/README.md` to stay consistent. This might come in handy if the chat platform changes at a later point again.
Shrink Unicode tables (even more)
This shrinks the Unicode tables further, building upon the wins in #68232 (the previous counts differ due to an interim Unicode version update, see #69929.
The new data structure is slower by around 3x, on the benchmark of looking up every Unicode scalar value in each data set sequentially in every data set included. Note that for ASCII, the exposed functions on `char` optimize with direct branches, so ASCII will retain the same performance regardless of internal optimizations (or the reverse). Also, note that the size reduction due to the skip list (from where the performance losses come) is around 40%, and, as a result, I believe the performance loss is acceptable, as the routines are still quite fast. Anywhere where this is hot, should probably be using a custom data structure anyway (e.g., a raw bitset) or something optimized for frequently seen values, etc.
This PR updates both the bitset data structure, and introduces a new data structure similar to a skip list. For more details, see the [main.rs] of the table generator, which describes both. The commits mostly work individually and document size wins.
As before, this is tested on all valid chars to have the same results as nightly (and the canonical Unicode data sets), happily, no bugs were found.
[main.rs]: https://github.com/rust-lang/rust/blob/fb4a715e18b/src/tools/unicode-table-generator/src/main.rs
Set | Previous | New | % of old | Codepoints | Ranges |
----------------|---------:|------:|-----------:|-----------:|-------:|
Alphabetic | 3055 | 1599 | 52% | 132875 | 695 |
Case Ignorable | 2136 | 949 | 44% | 2413 | 410 |
Cased | 934 | 359 | 38% | 4286 | 141 |
Cc | 43 | 9 | 20% | 65 | 2 |
Grapheme Extend | 1774 | 813 | 46% | 1979 | 344 |
Lowercase | 985 | 867 | 88% | 2344 | 652 |
N | 1266 | 419 | 33% | 1781 | 133 |
Uppercase | 934 | 777 | 83% | 1911 | 643 |
White_Space | 140 | 37 | 26% | 25 | 10 |
----------------|----------|-------|------------|------------|--------|
Total | 11267 | 5829 | 51% | - | - |
Create output dir in rustdoc markdown render
`rustdoc` command on a standalone markdown document fails because the output directory (which default to `doc/`) is not created, even when specified with the `--output` argument.
This PR adds the creation of the output directory before the file creation to avoid an unexpected error which is unclear.
I am not sure about the returned error code. I did not find a table explaining them. So I simply put the same error code that is returned when `File::create` fails because they are both related to file-system errors.
Resolve#70431
submodules: update clippy from 1ff81c1b to 70b93aab
Changes:
````
remove redundant import
rustup https://github.com/rust-lang/rust/pull/68404
rustup https://github.com/rust-lang/rust/pull/69644
rustup https://github.com/rust-lang/rust/pull/70344
Move verbose_file_reads to restriction
move redundant_pub_crate to nursery
readme: explain how to run only a single lint on a codebase
Remove dependency on `matches` crate
Move useless_transmute to nursery
nursery group -> style
Update for PR feedback
Auto merge of #5314 - ehuss:remove-git2, r=flip1995
Lint for `pub(crate)` items that are not crate visible due to the visibility of the module that contains them
````
Fixes#70456
