Fix syntax error in the compiler
Currently `rustc` accepts the following code: `fn f<'a>() where 'a {}`. This should be a syntax error, shouldn't it?
Not sure if my changes actually compile, waiting for the LLVM to build.
Don't spin expanding stmt macros.
If we can't make progress when parsing a macro expansion as a statement then we should just bail.
This alleviates the symptoms shown in e.g. #37113 and #37234 but it doesn't fix the problem that parsing invalid enum bodies (and others) leaves the parser in a crappy state.
I'm not sold on this strategy (checking `tokens_consumed`), so if anyone has a better idea, I'm all ears!
The new handling fixed a latent bug in the parser error handling where
it would only abort after the second error (when configured to stop
after the first error). This is because the check for `error_count != 0`
was occuring before the increment. Since the increment is tied to the
`emit()` call now this no longer occurs.
Most of the Rust community agrees that the vec! macro is clearer when
called using square brackets [] instead of regular brackets (). Most of
these ocurrences are from before macros allowed using different types of
brackets.
There is one left unchanged in a pretty-print test, as the pretty
printer still wants it to have regular brackets.
Recover out of an enum or struct's braced block.
If we encounter a syntax error inside of a braced block, then we should
fail by consuming the rest of the block if possible.
This implements such recovery for enums and structs.
Fixes#37113.
If we can't make progress when parsing a macro expansion as a statement
then we should just bail.
This alleviates the symptoms shown in e.g. #37113 but it doesn't fix the
problem that parsing invalid enum bodies (and others) leaves the parser
in a crappy state.
If we encounter a syntax error inside of a braced block, then we should
fail by consuming the rest of the block if possible.
This implements such recovery for enums and structs.
Fixes#37113.
Specific error message for missplaced doc comments
Identify when documetation comments have been missplaced in the following places:
* After a struct element:
```rust
// file.rs:
struct X {
a: u8 /** document a */,
}
```
```bash
$ rustc file.rs
file.rs:2:11: 2:28 error: found documentation comment that doesn't
document anything
file.rs:2 a: u8 /** document a */,
^~~~~~~~~~~~~~~~~
file.rs:2:11: 2:28 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
* As the last line of a struct:
```rust
// file.rs:
struct X {
a: u8,
/// incorrect documentation
}
```
```bash
$ rustc file.rs
file.rs:3:5: 3:27 error: found a documentation comment that doesn't
document anything
file.rs:3 /// incorrect documentation
^~~~~~~~~~~~~~~~~~~~~~
file.rs:3:5: 3:27 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
* As the last line of a `fn`:
```rust
// file.rs:
fn main() {
let x = 1;
/// incorrect documentation
}
```
```bash
$ rustc file.rs
file.rs:3:5: 3:27 error: found a documentation comment that doesn't
document anything
file.rs:3 /// incorrect documentation
^~~~~~~~~~~~~~~~~~~~~~
file.rs:3:5: 3:27 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
Fix#27429, #30322
Identify when documetation comments have been missplaced in the
following places:
* After a struct element:
```rust
// file.rs:
struct X {
a: u8 /** document a */,
}
```
```bash
$ rustc file.rs
file.rs:2:11: 2:28 error: found documentation comment that doesn't
document anything
file.rs:2 a: u8 /** document a */,
^~~~~~~~~~~~~~~~~
file.rs:2:11: 2:28 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
* As the last line of a struct:
```rust
// file.rs:
struct X {
a: u8,
/// incorrect documentation
}
```
```bash
$ rustc file.rs
file.rs:3:5: 3:27 error: found a documentation comment that doesn't
document anything
file.rs:3 /// incorrect documentation
^~~~~~~~~~~~~~~~~~~~~~
file.rs:3:5: 3:27 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
* As the last line of a `fn`:
```rust
// file.rs:
fn main() {
let x = 1;
/// incorrect documentation
}
```
```bash
$ rustc file.rs
file.rs:3:5: 3:27 error: found a documentation comment that doesn't
document anything
file.rs:3 /// incorrect documentation
^~~~~~~~~~~~~~~~~~~~~~
file.rs:3:5: 3:27 help: doc comments must come before what they document,
maybe a comment was intended with `//`?
```
Fix#27429, #30322
Fix spans and expected token lists, fix#33413 + other cosmetic improvements
Add test for #33413
Convert between `Arg` and `ExplicitSelf` precisely
Simplify pretty-printing for methods
parser: do not try to continue with `unsafe` on foreign fns
The changed line makes it look like `unsafe` is allowed, but the first statement of `parse_item_foreign_fn` is:
```
self.expect_keyword(keywords::Fn)?;
```
So we get the strange "expected one of `fn`, `pub`, `static`, or `unsafe`, found `unsafe`".
Fixes: #27361
parser: fix suppression of syntax errors in range RHS
Invalid expressions on the RHS were just swallowed without generating an error. The new version more closely mirrors the code for parsing `..x` in the `parse_prefix_range_expr` method below, where no cancel is done either.
Fixes#33262.
The changed line makes it look like `unsafe` is allowed, but the
first statement of `parse_item_foreign_fn` is:
`self.expect_keyword(keywords::Fn)?;`
So we get the strange "expected one of `fn`, `pub`, `static`, or
`unsafe`, found `unsafe`".
Fixes: #27361
Invalid expressions on the RHS were just swallowed without generating
an error. The new code more closely mirrors the code for parsing
`..x` in the `parse_prefix_range_expr` method, where no cancel is done
either.
Fixes#33262.
syntax: Merge PathParsingMode::NoTypesAllowed and PathParsingMode::ImportPrefix
syntax: Rename PathParsingMode and its variants to better express their purpose
syntax: Remove obsolete error message about 'self lifetime
syntax: Remove ALLOW_MODULE_PATHS workaround
syntax/resolve: Adjust some error messages
resolve: Compare unhygienic (not renamed) names with keywords::Invalid, invalid identifiers may appear to be valid after renaming
This uncovered a lot of bugs in compiletest and also some shortcomings
of our existing JSON output. We had to add information to the JSON
output, such as suggested text and macro backtraces. We also had to fix
various bugs in the existing tests.
Joint work with jntrnr.
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.
