Integrate privacy into field and method selection
This PR integrates privacy checking into field and method selection so that an inaccessible field/method can not stop an accessible field/method from being used (fixes#12808 and fixes#22684).
r? @eddyb
Gate parser recovery via debugflag
Gate parser recovery via debugflag
Put in `-Z continue_parse_after_error`
This works by adding a method, `fn abort_if_no_parse_recovery`, to the
diagnostic handler in `syntax::errors`, and calling it after each
error is emitted in the parser.
(We might consider adding a debugflag to do such aborts in other
places where we are currently attempting recovery, such as resolve,
but I think the parser is the really important case to handle in the
face of #31994 and the parser bugs of varying degrees that were
injected by parse error recovery.)
r? @nikomatsakis
parser recovery (so that expected errors match up)
I'm opting into parser recovery in all these cases out of expediency,
not because the error messages you get with recovery enabled are
actually all that usable in all cases listed.
Prevent bumping the parser past the EOF.
Makes `Parser::bump` after EOF into an ICE, forcing callers to avoid repeated EOF bumps.
This ICE is intended to break infinite loops where EOF wasn't stopping the loop.
For example, the handling of EOF in `parse_trait_items`' recovery loop fixes#32446.
But even without this specific fix, the ICE is triggered, which helps diagnosis and UX.
This is a `[breaking-change]` for plugins authors who eagerly eat multiple EOFs.
See https://github.com/docopt/docopt.rs/pull/171 for such an example and the necessary fix.
melt the ICE when lowering an impossible range
Emit a fatal error instead of panicking when HIR lowering encounters a range with no `end` point.
This involved adding a method to wire up `LoweringContext::span_fatal`.
Fixes#32245 (cc @nodakai).
r? @nrc
End-less ranges (`a...`) don't parse but bad syntax extensions could
conceivably produce them. Unbounded ranges (`...`) do parse and are
caught here.
The other panics in HIR lowering are all for unexpanded macros, which
cannot be constructed by bad syntax extensions.
Make errors for unnecessary visibility qualifiers consistent
This PR refactors away `syntax::parse::parser::ParsePub` so that unnecessary visibility qualifiers on variant fields are reported not by the parser but by `privacy::SanePrivacyVisitor` (thanks to @petrochenkov's drive-by improvements in #31919).
r? @nikomatsakis
Mostly copy the tests from half-open ranges, adding some more for
DoubleEndedIterator and ExactSizeIterator.
Also thoroughly (I think) test that the feature gates are working.
Some tests just add the extra errors, others I fix by doing some simple error recovery. I've tried to avoid doing too much in the hope of doing something more principled later.
In general error messages are getting worse at this stage, but I think in the long run they will get better.
Previously when breaking tokens into smaller pieces, the replace_token
function have been used. It replaced current token and updated span
information, but it did not clear the list of expected tokens, neither
did it update remaining info about last token. This could lead to
incorrect error message, like one described in the issue #24780:
expected one of ... `>` ... found `>`
This is achieved by adding the scan_back method. This method looks back
through the source_text of the StringReader until it finds the target
char, returning it's offset in the source. We use this method to find
the offset of the opening single quote, and use that offset as the start
of the error.
Given this code:
```rust
fn main() {
let _ = 'abcd';
}
```
The compiler would give a message like:
```
error: character literal may only contain one codepoint: ';
let _ = 'abcd';
^~
```
With this change, the message now displays:
```
error: character literal may only contain one codepoint: 'abcd';
let _ = 'abcd';
^~~~~~~
```
Fixes#30033
Given this code:
fn main() {
let _ = 'abcd';
}
The compiler would give a message like:
error: character literal may only contain one codepoint: ';
let _ = 'abcd';
^~
With this change, the message now displays:
error: character literal may only contain one codepoint: 'abcd'
let _ = 'abcd'
^~~~~~
Fixes#30033
The motivation (other than removing boilerplate) is that this is a baby step towards a parser with error recovery.
[breaking-change] if you use any of the changed functions, you'll need to remove a try! or panictry!
The current help message is too much about "normal" macros to be used
as general message. Keep it for normal macros, and add custom help and
error messages for macro definitions.
nodes in statement position.
Extended #[cfg] folder to allow removal of statements, and
of expressions in optional positions like expression lists and trailing
block expressions.
Extended lint checker to recognize lint levels on expressions and
locals.
If you try to put something that's bigger than a char into a char
literal, you get an error:
fn main() {
let c = 'ஶ்ரீ';
}
error: unterminated character constant:
This is a very compiler-centric message. Yes, it's technically
'unterminated', but that's not what you, the user did wrong.
Instead, this commit changes it to
error: character literal may only contain one codepoint
As this actually tells you what went wrong.
Fixes#28851
This commit generalises parsing of associative operators from left-associative
only (with some ugly hacks to support right-associative assignment) to properly
left/right-associative operators.
Parsing still is not general enough to handle non-associative,
non-highest-precedence prefix or non-highest-precedence postfix operators (e.g.
`..` range syntax), though. That should be fixed in the future.
Lastly, this commit adds support for parsing right-associative `<-` (left arrow)
operator with precedence higher than assignment as the operator for placement-in
feature.
Previously, if you copied a signature from a trait definition such as:
```
fn foo<'a>(&'a Bar) -> bool {}
```
and moved it into an `impl`, there would be an error message:
"unexpected token `'a`"
Adding to the error message that a pattern is expected should help
users to find the actual problem with using a lifetime here.
This pull request implements the functionality for [RFC 873](https://github.com/rust-lang/rfcs/blob/master/text/0873-type-macros.md). This is currently just an update of @freebroccolo's branch from January, the corresponding commits are linked in each commit message.
@nikomatsakis and I had talked about updating the macro language to support a lifetime fragment specifier, and it is possible to do that work on this branch as well. If so we can (collectively) talk about it next week during the pre-RustCamp work week.
