Suggest call fn ctor passed as arg to fn with type param bounds
_Reviewer note: the relevant changes are in the second commit, the first is simple and mechanical, but verbose._
When forgetting to call a fn in an argument position to an fn that has a generic bound:
```rust
async fn foo() {}
fn bar(f: impl Future<Output=()>) {}
fn main() {
bar(foo); // <- should be `bar(foo());`
}
```
suggest calling it:
```
error[E0277]: the trait bound `fn() -> impl std::future::Future {foo}: std::future::Future` is not satisfied
--> $DIR/async-fn-ctor-passed-as-arg-where-it-should-have-been-called.rs:9:5
|
LL | fn bar(f: impl Future<Output=()>) {}
| --------------------------------- required by `bar`
...
LL | bar(foo);
| ^^^ the trait `std::future::Future` is not implemented for `fn() -> impl std::future::Future {foo}`
|
= help: it looks like you forgot to use parentheses to call the function: `foo()`
```
Fix#63100. Follow up to #63833 and #63337.
Rollup of 5 pull requests
Successful merges:
- #63410 (Update BufWriter example to include call to flush())
- #64029 (Account for rounding errors when deciding the diagnostic boundaries)
- #64032 (rustdoc use -Ccodegen-units=1 by default for test compile)
- #64039 (Update sync condvar doc style)
- #64042 (Fix word repetition in str documentation)
Failed merges:
r? @ghost
An initial refactoring before working on #61809.
This moves the whole block into a method so that it can be reused in the
annotate-snippet output. It's already used in the new emitter, but
there's no UI tests with suggestions included in this PR.
A first look at some UI tests with suggestions showed that there's some
more work to do in [annotate-snippet-rs][annotate-snippet-rs] before the
new output is closer to the current one.
rustdoc use -Ccodegen-units=1 by default for test compile
as the test is small we do not want split up in multiple codegen units
and also as there is multiple test running at the same time this
will reduce the number of concurrent threads
tested the test time with `./x.py test src/libcore --doc`
for my 16 core 32 thread cpu i get about 6% faster execution
and my 2 core 4 thread cpu I get about 10% faster execution
cc #63638
r? @Mark-Simulacrum
Update BufWriter example to include call to flush()
I was playing with a writing a Huffman encoder/decoder and was getting weird corruptions and truncations. I finally realized it was was because `BufWriter` was swallowing write errors 😬. I've found Rust to generally be explicit and err on the safe side, so I definitely found this unintuitive and not "rustic".
https://twitter.com/johnterickson/status/1159514988123312128
use the code generation parameter -Clinker (same parameter as rustc)
to control what linker to use for building the rustdoc test executables.
closes: #63816
LLDB's expression parser can't unambiguously resolve local variables in
some cases, as described in #47938. Work around this by using names that
don't shadow direct submodules of `core`.
rustdoc: warn on empty doc test
Closes#60319.
A doc test that only contains whitespace should result in a warning.
This PR adds detection of empty doc tests to `check-code-block-syntax`, as having an invalid doc test is mutually exclusive with an empty doc test.
