Simplify checked_duration_since
This follows the same design as we updated to in #56490. Internally, all the system specific time implementations are checked, no panics. Then the panicking publicly exported API can just call the checked version of itself and make do with a single panic (`expect`) at the top.
Since the internal sys implementations are now checked, this gets rid of the extra `if self >= &earlier` check in `checked_duration_since`. Except likely making the generated machine code simpler, it also reduces the algorithm from "Check panic condition -> call possibly panicking method" to just "call non panicking method".
Added two test cases:
* Edge case: Make sure `checked_duration_since` on two equal `Instant`s produce a zero duration, not a `None`.
* Most common/intended usage: Make sure `later.checked_duration_since(earlier)`, returns an expected value.
Demo `FromIterator` short-circuiting
while looking at a FIXME in `FromIterator for Option` and `FromIterator for Result`, I realized that the current documentation does not have example code showing exactly what is meant by "no further elements are taken."
The code snippets provided here are meant to correct that.
Update build instructions in README.md
Add additional instructions when `sudo ./x.py install` fails to
complete the build.
This resolves issues #40108 and #49269.
r? @steveklabnik
Provide suggestion when using field access instead of path
When trying to access an associated constant as if it were a field of
an instance, provide a suggestion for the correct syntax.
Fix#57316.
SGX target: fix std unit tests
This fixes some tests and some code in the SGX sys implementation to make the `std` unit test suite pass.
#59009 must be merged first.
filter suggestions from extern prelude
Fixes#59027.
Modifies the candidate gathering code to call `filter_fn` on extern crates, which causes them to be filtered out when looking for a type.
make asm diagnostic instruction optional
`DiagnosticInfoInlineAsm::getInstruction` may return a null pointer, so
the instruction shouldn't be blindly unwrapped.
Reopening from #55193. I was unable to trigger the assertion on Windows after rebasing.
Fixes#23458.
Fixes#55216.
When moving out of a for loop head, suggest borrowing it
When encountering code like the following, suggest borrowing the for loop
head to avoid moving it into the for loop pattern:
```
fn main() {
let a = vec![1, 2, 3];
for i in &a {
for j in a {
println!("{} * {} = {}", i, j, i * j);
}
}
}
```
Fix#25534.
When encountering code like the following, suggest borrowing the for loop
head to avoid moving it into the for loop pattern:
```
fn main() {
let a = vec![1, 2, 3];
for i in &a {
for j in a {
println!("{} * {} = {}", i, j, i * j);
}
}
}
```
Rollup of 7 pull requests
Successful merges:
- #59213 (Track changes to robots.txt)
- #59239 (Remove inline assembly from hint::spin_loop)
- #59251 (Use a valid name for graphviz graphs)
- #59296 (Do not encode gensymed imports in metadata)
- #59328 (Implement specialized nth_back() for Box and Windows.)
- #59355 (Fix ICE with const generic param in struct)
- #59377 (Correct minimum system LLVM version in tests)
This commit removes `CtorOf` from `Node::Ctor` as the parent of the
constructor can be determined by looking at the node's parent in the few
places where knowing this is necessary.
Correct minimum system LLVM version in tests
Since commit 9452a8dfa3, the new debug info format is only generated
for LLVM 8 and newer versions. However, the tests still assume that LLVM
7 will use the new debug info format. Fix the tests (and a comment in
the code) to match the actual version check.
(WIP) Small fixes in chalkification
Small fixes around region constraints and builtin impls. There are still some type inference errors, for example the following code errors out:
```rust
fn main() {
let mut x: Vec<i32> = Vec::new();
// ^^^^^^^^ cannot infer type for `std::vec::Vec<_>`
}
```
but explicitly specifying `Vec::<i32>::new` works.
With these few fixes, the following code now passes type-checking:
```rust
fn main() {
let mut x: Vec<i32> = Vec::<i32>::new();
x.push(5);
println!("{:?}", x);
}
```
I also fixed the implied bounds bug as discussed on Zulip and in https://github.com/rust-lang-nursery/chalk/pull/206
cc @tmandry
r? @nikomatsakis
Implement specialized nth_back() for Box and Windows.
Hi there, this is my first pull request to rust :-)
I started implementing some specializations for DoubleEndedIterator::nth_back() and these are the first two. The problem has been discussed in #54054 and nth_back() is tracked in #56995.
I'm stuck with the next implementation so I though I do a PR for the ones I'm confident with to get some feedback.
Do not encode gensymed imports in metadata
(Unless they are underscore `_` imports which are re-gensymed on crate loading, see https://github.com/rust-lang/rust/pull/56392.)
We cannot encode gensymed imports properly in metadata and if we encode them improperly, we can get erroneous name conflicts downstream.
Gensymed imports are produced by the compiler, so we control their set, and can be sure that none of them needs being encoded for use from other crates.
A workaround that fixes https://github.com/rust-lang/rust/issues/59243.
Use a valid name for graphviz graphs
Hiridification has broken graphviz output because `HirId` has a more complex display implemetation than `NodeId`. Since the id was just used to generate a distinct identifier, we just pull out the various constituent indexed.
This commit makes two changes - separating the `NodeId` that identifies
an enum variant from the `NodeId` that identifies the variant's
constructor; and no longer creating a `NodeId` for `Struct`-style enum
variants and structs.
Separation of the variant id and variant constructor id will allow the
rest of RFC 2008 to be implemented by lowering the visibility of the
variant's constructor without lowering the visbility of the variant
itself.
No longer creating a `NodeId` for `Struct`-style enum variants and
structs mostly simplifies logic as previously this `NodeId` wasn't used.
There were various cases where the `NodeId` wouldn't be used unless
there was an unit or tuple struct or enum variant but not all uses of
this `NodeId` had that condition, by removing this `NodeId`, this must
be explicitly dealt with. This change mostly applied cleanly, but there
were one or two cases in name resolution and one case in type check
where the existing logic required a id for `Struct`-style enum variants
and structs.
