Previously:
error: invalid format string: invalid argument name `_x`
--> src/main.rs:2:16
|
2 | println!("{_x}", a=0);
| ^^ invalid argument name in format string
|
= note: argument names cannot start with an underscore
Not supporting identifiers starting with underscore appears to have been
an arbitrary limitation from 2013 in code that was most likely never
reviewed:
https://github.com/rust-lang/rust/pull/8245/files#diff-0347868ef389c805e97636623e4a4ea6R277
The error message was dutifully improved in #50610 but is there any
reason that leading underscore would be a special case?
This commit updates the format_args parser to accept identifiers with
leading underscores.
When a formatting string contains an invalid descriptor, point at it
instead of the argument:
```
error: unknown format trait `foo`
--> $DIR/ifmt-bad-arg.rs:86:17
|
LL | println!("{:foo}", 1);
| ^^^
|
= note: the only appropriate formatting traits are:
- ``, which uses the `Display` trait
- `?`, which uses the `Debug` trait
- `e`, which uses the `LowerExp` trait
- `E`, which uses the `UpperExp` trait
- `o`, which uses the `Octal` trait
- `p`, which uses the `Pointer` trait
- `b`, which uses the `Binary` trait
- `x`, which uses the `LowerHex` trait
- `X`, which uses the `UpperHex` trait
```
They are only used by rustc_lexer, and are not needed elsewhere.
So we move the relevant definitions into rustc_lexer (while the actual
unicode data comes from the unicode-xid crate) and make the rest of
the compiler use it.
On `format!()` arg count mismatch provide extra info
When positional width and precision formatting flags are present in a
formatting string that has an argument count mismatch, provide extra
information pointing at them making it easiser to understand where the
problem may lay:
```
error: 4 positional arguments in format string, but there are 3 arguments
--> $DIR/ifmt-bad-arg.rs:78:15
|
LL | println!("{} {:.*} {}", 1, 3.2, 4);
| ^^ ^^--^ ^^ --- this parameter corresponds to the precision flag
| |
| this precision flag adds an extra required argument at position 1, which is why there are 4 arguments expected
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
error: 4 positional arguments in format string, but there are 3 arguments
--> $DIR/ifmt-bad-arg.rs:81:15
|
LL | println!("{} {:07$.*} {}", 1, 3.2, 4);
| ^^ ^^-----^ ^^ --- this parameter corresponds to the precision flag
| | |
| | this precision flag adds an extra required argument at position 1, which is why there are 4 arguments expected
| this width flag expects an `usize` argument at position 7, but there are 3 arguments
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
error: invalid reference to positional argument 7 (there are 3 arguments)
--> $DIR/ifmt-bad-arg.rs:84:18
|
LL | println!("{} {:07$} {}", 1, 3.2, 4);
| ^^^--^
| |
| this width flag expects an `usize` argument at position 7, but there are 3 arguments
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
```
Fix#49384.
When positional width and precision formatting flags are present in a
formatting string that has an argument count mismatch, provide extra
information pointing at them making it easiser to understand where the
problem may lay:
```
error: 4 positional arguments in format string, but there are 3 arguments
--> $DIR/ifmt-bad-arg.rs:78:15
|
LL | println!("{} {:.*} {}", 1, 3.2, 4);
| ^^ ^^--^ ^^ --- this parameter corresponds to the precision flag
| |
| this precision flag adds an extra required argument at position 1, which is why there are 4 arguments expected
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
error: 4 positional arguments in format string, but there are 3 arguments
--> $DIR/ifmt-bad-arg.rs:81:15
|
LL | println!("{} {:07$.*} {}", 1, 3.2, 4);
| ^^ ^^-----^ ^^ --- this parameter corresponds to the precision flag
| | |
| | this precision flag adds an extra required argument at position 1, which is why there are 4 arguments expected
| this width flag expects an `usize` argument at position 7, but there are 3 arguments
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
error: 3 positional arguments in format string, but there are 3 arguments
--> $DIR/ifmt-bad-arg.rs:84:15
|
LL | println!("{} {:07$} {}", 1, 3.2, 4);
| ^^ ^^---^ ^^
| |
| this width flag expects an `usize` argument at position 7, but there are 3 arguments
|
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
```
Use Symbol, Span in libfmt_macros
I'm not super happy with this, personally, but I think it might be a decent start -- happy to take suggestions as to how to expand this or change things further.
r? @estebank
Fixes#60795
This should be used when trying to get at subsets of a larger span,
especially when the larger span is not available in the code attempting
to work with those subsets (especially common in the fmt_macros crate).
This is usually a good replacement for (BytePos, BytePos) and (usize,
usize) tuples.
This commit also removes from_inner_byte_pos, since it took usize
arguments, which is error prone.
Fix some minor warnings
Since apparently RLS works when initialized in the root repository (🎉) I decided to fix some of the issues it caught.
There are a lot of unused attribute warnings left on `rustc_on_unimplemented` and `rustc_layout_scalar_valid_range_start` but I imagine we can't do much about it due to 2-stage compilation?
When a format string has escaped whitespace characters format
arguments were shifted by one per each escaped character. Account
for these escaped characters when synthesizing the spans.
Fix#55155.
- Point at opening mismatched formatting brace
- Account for differences between raw and regular strings
- Account for differences between the code snippet and `InternedString`
- Add more tests
Rollup of bare_trait_objects PRs
All deny attributes were moved into bootstrap so they can be disabled with a line of config.
Warnings for external tools are allowed and it's up to the tool's maintainer to keep it warnings free.
r? @Mark-Simulacrum
cc @ljedrz @kennytm
