Add filtering option to `rustc_on_unimplemented` and reword `Iterator` E0277 errors
- Add more targetting filters for arrays to `rustc_on_unimplemented` (Fix#53766)
- Detect one element array of `Range` type, which is potentially a typo:
`for _ in [0..10] {}` where iterating between `0` and `10` was intended.
(Fix#23141)
- Suggest `.bytes()` and `.chars()` for `String`.
- Suggest borrowing or `.iter()` on arrays (Fix#36391)
- Suggest using range literal when iterating on integers (Fix#34353)
- Do not suggest `.iter()` by default (Fix#50773, fix#46806)
- Add regression test (Fix#22872)
reject partial init and reinit of uninitialized data
Reject partial initialization of uninitialized structured types (i.e. structs and tuples) and also reject partial *reinitialization* of such types.
Fix#54986Fix#54499
cc #21232
E0669 refers to a constraint that cannot be coerced into a single LLVM
value, unfortunately right now this uses the Span for the entire inline
assembly statement, which is less than ideal.
This commit preserves the Span from HIR, which lets us emit the error
using the Span for the operand itself in MIR.
Signed-off-by: Levente Kurusa <lkurusa@acm.org>
Aaron Hill pointed out that unnecessary parens around a macro call
(paradigmatically, `format!`) yielded a suggestion of hideous
macro-expanded code. (The slightly unusual choice of using the
pretty-printer to compose suggestions was quite recently commented on
in the commit message for 1081bbbfc ("abolish ICE when pretty-printing
async block"), but without any grounds to condemn it as a 𝘣𝘢𝘥
choice. Hill's report provides the grounds.) `span_to_snippet` is
fallable as far as the type system is concerned (because, who knows,
macros or something), so the pretty-printing can live on in the
oft-neglected `else` branch.
Resolves#55109.
resolve: Scale back hard-coded extern prelude additions on 2015 edition
https://github.com/rust-lang/rust/pull/54404 stabilized `feature(extern_prelude)` on 2015 edition, including the hard-coded parts not passed with `--extern`.
First of all, I'd want to confirm that this is intended stabilization, rather than a part of the "extended beta" scheme that's going to be reverted before releasing stable.
(EDIT: to clarify - this is a question, I'm \*asking\* for confirmation, rather than give it.)
Second, on 2015 edition extern prelude is not so fundamentally tied to imports and is a mere convenience, so this PR scales them back to the uncontroversial subset.
The "uncontroversial subset" means that if libcore is injected it brings `core` into prelude, if libstd is injected it brings `std` and `core` into prelude.
On 2015 edition this can be implemented through the library prelude (rather than hard-coding in the compiler) right now, I'll do it in a follow-up PR.
UPDATE: The change is done for both 2015 and 2018 editions now as discussed below.
Closes https://github.com/rust-lang/rust/issues/53166
nll type annotations in multisegment path
This turned out to be sort of tricky. The problem is that if you have a path like
```
<Foo<&'static u32>>::bar
```
and it comes from an impl like `impl<T> Foo<T>` then the self-type the user gave doesn't *directly* map to the substitutions that the impl wants. To handle this, then, we have to preserve not just the "user-given substs" we used to do, but also a "user-given self-ty", which we have to apply later. This PR makes those changes.
It also removes the code from NLL relate-ops that handled canonical variables and moves to use normal inference variables instead. This simplifies a few things and gives us a bit more flexibility (for example, I predict we are going to have to start normalizing at some point, and it would be easy now).
r? @matthewjasper -- you were just touching this code, do you feel comfortable reviewing this?
Fixes#54574
This commit updates the test output for the updated NLL compare mode
that uses `-Z borrowck=migrate` rather than `-Z borrowck=mir`. The
previous commit changes `compiletest` and this commit only updates
`.nll.stderr` files.
Add missing lifetime fragment specifier to error message.
A very minor issue, `lifetime` was missing from the error list.
I left `literal` in the list, even though it is unstable. It looks like it may stabilize soon anyways.
* `ui/lifetimes/lifetime-errors/ex3-both-anon-regions-both-are-structs-4`
and `ex3-both-anon-regions-both-are-structs-3`
* `ui/lint/lint-group-style` and `lint-group-nonstandard-style`
`#[must_use]` for associated functions is supposed to actually work
In the comments of (closed, defunct) pull request #54884, @Centril [noted that](https://github.com/rust-lang/rust/pull/54884#issuecomment-427626495) must-use annotations didn't work on an associated function (what other communities might call a "static method"). Subsequent logging revealed that in this case we have a `Def::Method`, whereas the lint pass was only matching on `Def::Fn`. (One could argue that those def-names are thereby misleading—must-use for `self`-ful methods have always worked—but documenting or reworking that can be left to another day.)
r? @varkor
The #[panic_handler] attribute can be applied to non-functions
Fixes#54896.
This commit extends the existing lang items functionality to assert
that the `#[lang_item]` attribute is only found on the appropriate item
for any given lang item. That is, language items representing traits
must only ever have their corresponding attribute placed on a trait, for
example.
r? @nagisa
structured suggestion for E0223 ambiguous associated type
(routine (and when are we going to be done finding these, anyway?) but something that stuck out to me while glancing at #54970)
r? @estebank
In the comments of (closed, defunct) pull request #54884, Mazdak
"Centril" Farrokhzad noted that must-use annotations didn't work on an
associated function (what other communities might call a "static
method"). Subsequent logging revealed that in this case we have a
`Def::Method`, whereas the lint pass was only matching on
`Def::Fn`. (One could argue that those def-names are thereby
misleading—must-use for self-ful methods have always worked—but
documenting or reworking that can be left to another day.)
A very minor issue, `lifetime` was missing from the error list.
I left `literal` in the list, even though it is unstable. It looks like it may stabilize soon anyways.
[NLL] Check user types are well-formed
Also contains a change of span for AscribeUserType.
I'm not quite sure if this was what @nikomatsakis was thinking.
Closes#54620
r? @nikomatsakis
