This improves #32077, but is not a complete fix. For a type alias `type
NewType = AliasedType`, it will include any `impl NewType` and `impl
Trait for NewType` blocks in the documentation for `NewType`.
A complete fix would include the implementations from the aliased type
in the type alias' documentation, so that users have a complete
picture of methods that are available on the alias. However, to do this
properly would require a fix for #14072, as the alias may affect the
type parameters of the type alias, making the documentation difficult to
understand. (That is, for `type Result = std::result::Result<(), ()>` we
would ideally show documentation for `impl Result<(), ()>`, rather than
generic documentation for `impl<T, E> Result<T, E>`).
I think this improvement is worthwhile, as it exposes implementations
which are not currently documented by rustdoc. The documentation for the
implementations on the aliased type are still accessible by clicking
through to the docs for that type. (Although perhaps it's now less
obvious to the user that they should click-through to get there).
Better closure error message
Use tracked data introduced in #42196 to provide a better closure
error message by showing why a closure implements `FnOnce`.
```
error[E0525]: expected a closure that implements the `Fn` trait, but
this closure only implements `FnOnce`
--> $DIR/issue_26046.rs:4:19
|
4 | let closure = move || {
| ___________________^
5 | | vec
6 | | };
| |_____^
|
note: closure is `FnOnce` because it moves the variable `vec` out of
its environment
--> $DIR/issue_26046.rs:5:9
|
5 | vec
| ^^^
error: aborting due to previous error(s)
```
Fixes#26046
r? @nikomatsakis
cc @doomrobo
Changing error message from `contains interior mutability` to `may contain interior mutability`
Fixes#40313 . I have changed the message from `contains interior mutability` to `may contain interior mutability` for the following example
```
use std::cell::Cell;
use std::panic::catch_unwind;
fn main() {
let mut x = Cell::new(22);
catch_unwind(|| { x.set(23); });
}
```
which has been added as a ui test.
Also, the message [here](https://github.com/gaurikholkar/rust/blob/master/src/librustc_mir/transform/qualify_consts.rs#L666) and it's respective `compile-fail` test have been modified.
cc @nikomatsakis @Mark-Simulacrum @eddyb
rustc: T: 'empty always holds for all types.
Fixes#42467 by special-casing `ReEmpty` to always hold, even for parameters.
The reason this is the case is that `ReEmpty` is the result of inferring a region variable with no constraints attached to it, so there is no lifetime a type would contain which would be strictly shorter.
r? @nikomatsakis
rustc_typeck: do not overlap a borrow of TypeckTables with method lookup.
If trait selection is reached, it could potentially request a closure signature, which will have to borrow the `TypeckTables` of the current function, and so those tables *should not* be mutably borrowed.
Fixes#42463.
r? @nikomatsakis
Add conversions from File and Child* handles to Stdio
`Stdio` now implements `From<ChildStdin>`, `From<ChildStdout>`,
`From<ChildStderr>`, and `From<File>`.
The `Command::stdin`/`stdout`/`stderr` methods now take any type that
implements `Into<Stdio>`.
This makes it much easier to write shell-like command chains, piping to
one another and redirecting to and from files. Otherwise one would need
to use the unsafe and OS-specific `from_raw_fd` or `from_raw_handle`.
`Stdio` now implements `From<ChildStdin>`, `From<ChildStdout>`,
`From<ChildStderr>`, and `From<File>`.
The `Command::stdin`/`stdout`/`stderr` methods now take any type that
implements `Into<Stdio>`.
This makes it much easier to write shell-like command chains, piping to
one another and redirecting to and from files. Otherwise one would need
to use the unsafe and OS-specific `from_raw_fd` or `from_raw_handle`.
add playbot jokes to run-pass test
Some funny expressions that people pull out on IRC, that might actually be useful to test pathological parser behavior.
Always quote program name in Command::spawn on Windows
[`CreateProcess`](https://msdn.microsoft.com/en-us/library/windows/desktop/ms682425.aspx) will interpret args as part of the binary name if it
doesn't find the binary using just the unquoted name. For example if
`foo.exe` doesn't exist, `Command::new("foo").arg("bar").spawn()` will
try to launch `foo bar.exe` which is clearly not desired.
Disallow underscore suffix for string-like literals.
This patch turns string/bytestring/char/byte literals followed by an underscore, like `"Foo"_`, to an error.
`scan_optional_raw_name` will parse `_` as a valid raw name, but it will be rejected by the parser. I also considered just stopping parsing when the suffix is `_`, but in that case `"Foo"_` will be lexed as two valid tokens.
Fixes the latter half of #41723.
Show trait method signature when impl differs
When the trait's span is available, it is already being used, add a
`note` for the cases where the span isn't available:
<pre>
error[E0053]: <b>method `fmt` has an incompatible type for trait</b>
--> $DIR/trait_type.rs:17:4
|
17 | fn fmt(&self, x: &str) -> () { }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ in mutability
|
= note: expected type `<b>fn(&MyType, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error></b>`
found type `<b>fn(&MyType, &str)</b>`
error[E0050]: <b>method `fmt` has 1 parameter but the declaration in trait `std::fmt::Display::fmt` has 2</b>
--> $DIR/trait_type.rs:21:11
|
21 | fn fmt(&self) -> () { }
| ^^^^^ expected 2 parameters, found 1
|
= note: `fmt` from trait: `<b>fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error></b>`
error[E0186]: <b>method `fmt` has a `&self` declaration in the trait, but not in the impl</b>
--> $DIR/trait_type.rs:25:4
|
25 | fn fmt() -> () { }
| ^^^^^^^^^^^^^^^^^^ expected `&self` in impl
|
= note: `fmt` from trait: `<b>fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error></b>`
error[E0046]: <b>not all trait items implemented, missing: `fmt`</b>
--> $DIR/trait_type.rs:28:1
|
28 | impl std::fmt::Display for MyType4 {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `fmt` in implementation
|
= note: `fmt` from trait: `<b>fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error></b>`
</code></pre>
Fix#28011.
When the trait's span is available, it is already being used, add a
`note` for the cases where the span isn't available:
```
error[E0053]: method `fmt` has an incompatible type for trait
--> $DIR/trait_type.rs:17:4
|
17 | fn fmt(&self, x: &str) -> () { }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ in mutability
|
= note: expected type `fn(&MyType, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error>`
found type `fn(&MyType, &str)`
error[E0050]: method `fmt` has 1 parameter but the declaration in trait `std::fmt::Display::fmt` has 2
--> $DIR/trait_type.rs:21:11
|
21 | fn fmt(&self) -> () { }
| ^^^^^ expected 2 parameters, found 1
|
= note: `fmt` from trait: `fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error>`
error[E0186]: method `fmt` has a `&self` declaration in the trait, but not in the impl
--> $DIR/trait_type.rs:25:4
|
25 | fn fmt() -> () { }
| ^^^^^^^^^^^^^^^^^^ expected `&self` in impl
|
= note: `fmt` from trait: `fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error>`
error[E0046]: not all trait items implemented, missing: `fmt`
--> $DIR/trait_type.rs:28:1
|
28 | impl std::fmt::Display for MyType4 {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `fmt` in implementation
|
= note: `fmt` from trait: `fn(&Self, &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error>`
```
Change for-loop desugar to not borrow the iterator during the loop
This is enables the use of suspend points inside for-loops in movable generators. This is illegal in the current desugaring as `iter` is borrowed across the body.
Introduce 'run-pass' header to 'ui' tests in compiletest. Fix issue #36516.
<del>`ui-run` test is a combination of `ui` test and `run-pass` test. It is used to test lint output.</del>
Added support of `// run-pass` header to `ui` tests.
The compiler message of each test must match the corresponding `*.stderr` file like the traditional `ui` tests. Additionally, the compiled output must be executed successfully like the `run-pass` test.
12 `run-pass`/`run-pass-fulldeps` tests are moved to `ui`/`ui-fulldeps` plus the headers. After this move, no `run-pass`/`run-pass-fulldeps` tests should rely on the compiler's JSON message. This allows us to stop passing `--error-format json` in run-pass tests, thus fixing #36516.
Use callsite's span for macro calls on suggestion
When suggesting an appropriate mutability for a macro call, use the call
span instead of the expanded macro's span.
```
error[E0308]: mismatched types
--> $DIR/coerce-suggestions.rs:48:9
|
48 | s = format!("foo");
| ^^^^^^^^^^^^^^ expected mutable reference, found struct `std::string::String`
|
= note: expected type `&mut std::string::String`
found type `std::string::String`
= help: try with `&mut format!("foo")`
= note: this error originates in a macro outside of the current crate
```
Fix#41858.
These methods can never be called through deref so there is no point
including them. For example you can't call `into_boxed_bytes` or
`into_string` on `String`.
querify layout and move param env out of the infcx
The main goal of this PR is to move the parameter environment *out* of the inference context. This is because the inference environment will soon be changing over the course of inference --- for example, when we enter into a `for<'a> fn(...)` type, we will push a new environment with an increasing universe index, rather than skolemizing the `'a` references. Similarly, each obligation will soon be able to have a distinct parameter environment, and therefore the `Obligation` struct is extended to carry a `ParamEnv<'tcx>`. (I debated about putting it into the cause; seems plausible, but also weird.)
Along the way, I also reworked how layout works, moving the layout cache into a proper query along the lines of needs-drop and friends.
Finally, tweaks the inference context API. It seemed to be accumulating parameters at an alarming rate. The main way to e.g. make a subtype or equality relationship is to do the following:
infcx.at(cause, param_env).sub(a, b)
infcx.at(cause, param_env).eq(a, b)
In both cases, `a` is considered the "expected" type (this used to be specified by a boolean). I tried hard to preserve the existing notion of what was "expected", although in some cases I'm not convinced it was being set on purpose one way or the other. This is why in some cases you will see me do `sup(b, a)`, which is otherwise equivalent to `sub(a, b)`, but sets the "expected type" differently.
r? @eddyb
cc @arielb1
The 'run-pass' header cause a 'ui' test to execute the result. It is used
to test the lint output, at the same time ensure those lints won't cause
the source code to become compile-fail.
12 run-pass/run-pass-fulldeps tests gained the header and are moved to
ui/ui-fulldeps. After this move, no run-pass/run-pass-fulldeps tests should
rely on the compiler's JSON message. This allows us to stop passing
`--error-format json` in run-pass tests, thus fixing #36516.
