Ever plagued by #43081 the compiler can return surprising spans in situations
related to procedural macros. This is exhibited by #47983 where whenever a
procedural macro is invoked in a nested item context it would fail to have
correct span information.
While #43230 provided a "hack" to cache the token stream used for each item in
the compiler it's not a full-blown solution. This commit continues to extend
this "hack" a bit more to work for nested items.
Previously in the parser the `parse_item` method would collect the tokens for an
item into a cache on the item itself. It turned out, however, that nested items
were parsed through the `parse_item_` method, so they didn't receive similar
treatment. To remedy this situation the hook for collecting tokens was moved
into `parse_item_` instead of `parse_item`.
Afterwards the token collection scheme was updated to support nested collection
of tokens. This is implemented by tracking `TokenStream` tokens instead of
`TokenTree` to allow for collecting items into streams at intermediate layers
and having them interleaved in the upper layers.
All in all, this...
Closes#47983
The existing elided-lifetimes-in-paths lint (introduced in Nov. 2017's
accd997b5 / #46254) lacked stuctured suggestions and—much more
alarmingly—produced false positives on associated functions (like
`Ref::clone`) and on anonymous '_ lifetimes (!!—yes, the very
anonymous lifetimes that we meant to suggest "instead"). That this
went apparently unnoticed for so long maybe tells you something about
how many people actually bother to flip on allow-by-default lints.
After many hours of good old-fashioned American elbow grease—and a
little help from expert reviewers—it turns out that getting the right
answer is a lot easier if we fire the lint while lowering the Higher
Intermediate Representation.
The lint is promoted to the idioms-2018 group.
Also, in the matter of test filenames, "elided" only has one 'l' (see,
e.g., https://en.wiktionary.org/wiki/elide).
Resolves#52041.
[NLL] Small move error reporting improvements
* Use a MirBorrowckContext when reporting errors to be more uniform with other error reporting
* Add a special message for the case of trying to move from capture variables in `Fn` and `FnMut` closures.
part of #51028
Improve suggestion for missing fmt str in println
Avoid using `concat!(fmt, "\n")` to improve the diagnostics being
emitted when the first `println!()` argument isn't a formatting string
literal.
Fix#52347.
LLVM isn't able to remove the alloca for the unaligned block in the SIMD tail in some cases, so doing this helps SRoA work in cases where it currently doesn't. Found in the `replace_with` RFC discussion.
This is a sequel to November 2017's #46103 / 1a9dc2e9. It had been
reported (more than once—at least #19140, #44083, and #44565) that the
"never used" language was confusing for enum variants that were "used"
as match patterns, so the wording was changed to say never
"constructed" specifically for enum variants. More recently, the same
issue was raised for structs (#52325). It seems consistent to say
"constructed" here, too, for the same reasons.
We considered using more specific word "called" for unused functions
and methods (while we declined to do this in #46103, the rationale
given in the commit message doesn't actually make sense), but it turns
out that Cargo's test suite expects the "never used" message, and
maybe we don't care enough even to make a Cargo PR over such a petty
and subjective wording change.
This resolves#52325.
Turn implied_outlives_bounds into a query
Right now all this does is remove the error reporting in `implied_outlives_bounds`, which seems to work. Farming out full tests to Travis.
For #51649. That issue is deferred so not sure what's next.
r? @nikomatsakis
When inserting a node N into the tree of impls, we sometimes find than
an existing node C should be replaced with N. We used to overwrite C
in place with the new def-id N -- but since the lists of def-ids are
separated by simplified type, that could lead to N being inserted in
the wrong place. This meant we might miss conflicts. We are now not
trying to be so smart -- we remove C and then add N later.
[NLL] Mutability errors
cc #51028
cc #51170
cc #46559Closes#46629
* Better explain why the place is immutable ("immutable item" is gone)
* Distinguish &T and *const T
* Use better spans when a mutable borrow is for a closure capture
r? @pnkfelix
resolve: Some renaming, refactoring and comments
Commits are self-descriptive.
The only functional change is 34bf2f572e that tightens shadowing rules for macro paths (makes the second and third cases in `test/ui/imports/glob-shadowing.rs` an error).
proc_macro: Preserve spans of attributes on functions
This commit updates the tokenization of items which are subsequently passed to
`proc_macro` to ensure that span information is preserved on attributes as much
as possible. Previously this area of the code suffered from #43081 where we
haven't actually implemented converting an attribute to to a token tree yet, but
a local fix was possible here.
Closes#47941
rustc: Fix two custom attributes with custom derive
This commit fixes an issue where multiple custom attributes could not be fed
into a custom derive in some situations with the `use_extern_macros` feature
enabled. The problem was that the macro expander didn't consider that it was
making progress when we were deducing that attributes should be lumped in with
custom derive invocations.
The fix applied here was to track in the expander if our attribute is changing
(getting stashed away elsewhere and replaced with a new invocation). If it is
swapped then it's considered progress, otherwise behavior should remain the
same.
Closes#52525
