Implement `#[proc_macro_attribute]`
This implements `#[proc_macro_attribute]` as described in https://github.com/rust-lang/rfcs/pull/1566
The following major (hopefully non-breaking) changes are included:
* Refactor `proc_macro::TokenStream` to use `syntax::tokenstream::TokenStream`.
* `proc_macro::tokenstream::TokenStream` no longer emits newlines between items, this can be trivially restored if desired
* `proc_macro::TokenStream::from_str` does not try to parse an item anymore, moved to `impl MultiItemModifier for CustomDerive` with more informative error message
* Implement `#[proc_macro_attribute]`, which expects functions of the kind `fn(TokenStream, TokenStream) -> TokenStream`
* Reactivated `#![feature(proc_macro)]` and gated `#[proc_macro_attribute]` under it
* `#![feature(proc_macro)]` and `#![feature(custom_attribute)]` are mutually exclusive
* adding `#![feature(proc_macro)]` makes the expansion pass assume that any attributes that are not built-in, or introduced by existing syntax extensions, are proc-macro attributes
* Fix `feature_gate::find_lang_feature_issue()` to not use `unwrap()`
* This change wasn't necessary for this PR, but it helped debugging a problem where I was using the wrong feature string.
* Move "completed feature gate checking" pass to after "name resolution" pass
* This was necessary for proper feature-gating of `#[proc_macro_attribute]` invocations when the `proc_macro` feature flag isn't set.
Prototype/Litmus Test: [Implementation](https://github.com/abonander/anterofit/blob/proc_macro/service-attr/src/lib.rs#L13) -- [Usage](https://github.com/abonander/anterofit/blob/proc_macro/service-attr/examples/post_service.rs#L35)
Implement placement-in protocol for `BinaryHeap`
Related to #30172, and loosley based on #38551.
At the moment, this PR is in a pretty rough state, but I wanted to get some feedback to see if I'm going in the right direction.
I hope the Mentor label of #30172 is still applicable, even though it's a year old 😄
This commit updates the compilers for many of the artifacts that we're producing
on Travis. These compilers are all compiled by crosstool-ng as they're currently
done for the images in which we're building all our cross compiled compilers.
The purpose of this commit is that when we ship binaries the artifacts won't
require a newer glibc, but rather be as compatible as possible with Linux
distributions by working with a very old version of glibc.
This commit always allocates a new matrix entry for the i686/x86_64 builder.
This builder is dedicated to just producing artifacts and eventually we'll
expand it to building other tools like Cargo and the RLS. The other builders
testing i686 and x86_64 won't use these historical toolchains.
This commit adds a new entry to the Travis matrix which will execute emscripten
test suites. Along the way it updates a few bits of the test suite to continue
passing on emscripten, such as:
* Ignoring i128/u128 tests as they're presumably just not working (didn't
investigate as to why)
* Disabling a few process tests (not working on emscripten)
* Ignore some num tests in libstd (#39119)
* Fix some warnings when compiling
Stop warning when doc testing proc macro crates
Fixes#39064
Add the test option to the session struct that is passed
to phase_2_configure_and_expand function inside the
rustdoc test module.
This prevents the warning code from triggering when
parsing proc_macro_derive attributes, just like when
`--test` is normally invoked.
This change makes the warning disappear, but I'm not sure what else it might change. So this early PR is mainly to run the test suite, and to get feedback.
The book currently claims that the `size` and `align` fields in the
trait object vtable are not used, but this is false. These two fields
are used by the stable `mem::size_of_val` and `mem::align_of_val`
functions.
See the `ty::TyDynamic` case of the `glue::size_and_align_of_dst`
function in librustc_trans, which is used to implement both intrinsics
in the unsized case.
A few improvements to the slice docs.
* Simplify `Option::iter_mut` doc example.
* Document 'empty' corner-cases for `slice::{starts_with, ends_with}`.
* Indicate 'true' as code-like.
collections: update docs of slice get() and friends
Resubmit of #38216.
r? @GuillaumeGomez
BTW, instead of closing a PR just because it is old and the team member who offered to fix it up did not have the time to do so, why not ping them instead? (cc @alexcrichton)
fs::metadata() follows symlinks so is_symlink() will always return
false. Use symlink_metadata instead in the example in the
documentation.
See issue #39088.
PartialEq and PartialOrd between IpAddr and Ipv[46]Addr.
PartialEq was rather useful, so, I figured that I'd implement it. I added PartialOrd for good measure.
