Commit Graph

581 Commits

Author SHA1 Message Date
Nicholas Nethercote
c6fedd4f10 Make MatcherPos not derive Clone.
It's only used in one place, and there we clone and then make a bunch of
modifications. It's clearer if we duplicate more explicitly, and there's
a symmetry now between `sequence()` and `empty_sequence()`.
2022-03-31 14:40:43 +11:00
Nicholas Nethercote
f68a0449ed Remove MatcherPos::stack.
`parse_tt` needs a way to get from within submatchers make to the
enclosing submatchers. Currently it has two distinct mechanisms for
this:
- `Delimited` submatchers use `MatcherPos::stack` to record stuff about
  the parent (and further back ancestors).
- `Sequence` submatchers use `MatcherPosSequence::parent` to point to
  the parent matcher position.

Having two mechanisms is really confusing, and it took me a long time to
understand all this.

This commit eliminates `MatcherPos::stack`, and changes `Delimited`
submatchers to use the same mechanism as sequence submatchers. That
mechanism is also changed a bit: instead of storing the entire parent
`MatcherPos`, we now only store the necessary parts from the parent
`MatcherPos`.

Overall this is a small performance win, with the positives outweighing
the negatives, but it's mostly for clarity.
2022-03-31 14:39:00 +11:00
Dylan DPC
1b7d6dbd30
Rollup merge of - nyurik:compiler-spell-comments, r=compiler-errors
Spellchecking compiler comments

This PR cleans up the rest of the spelling mistakes in the compiler comments. This PR does not change any literal or code spelling issues.
2022-03-31 04:57:28 +02:00
Nicholas Nethercote
048bd67d51 Clarify idx handling in sequences.
By adding comments, and improving an assertion. I finally fully
understand this part!
2022-03-31 11:48:36 +11:00
Nicholas Nethercote
2e423c7fd0 Remove MatcherPos::match_lo.
It's redundant w.r.t. other fields.
2022-03-31 11:48:35 +11:00
Nicholas Nethercote
21699c41af Simplify exit of Delimited submatchers.
Currently, we detect an exit from a `Delimited` submatcher when `idx`
exceeds the bounds of the current submatcher *and* there is a `stack`
entry.

This commit changes it to something simpler: just look for a
`CloseDelim` token.
2022-03-31 11:48:34 +11:00
Yuri Astrakhan
5160f8f843 Spellchecking compiler comments
This PR cleans up the rest of the spelling mistakes in the compiler comments. This PR does not change any literal or code spelling issues.
2022-03-30 15:14:15 -04:00
bors
c5cf08d37b Auto merge of - nnethercote:yet-more-parse_tt-improvements, r=petrochenkov
Yet more `parse_tt` improvements

Including lots of comment improvements, and an overhaul of how `matches` work that gives big speedups.

r? `@petrochenkov`
2022-03-30 19:08:01 +00:00
Yuri Astrakhan
7e8201ae0a Spellchecking some comments
This PR attempts to clean up some minor spelling mistakes in comments
2022-03-30 01:39:38 -04:00
Nicholas Nethercote
6b0a16ab1a Pre-allocate an empty Lrc<NamedMatchVec>.
This avoids some allocations.
2022-03-30 10:54:57 +11:00
Nicholas Nethercote
524d21bd54 Overhaul how matches are recorded.
Currently, matches within a sequence are recorded in a new empty
`matches` vector. Then when the sequence finishes the matches are merged
into the `matches` vector of the parent.

This commit changes things so that a sequence mp inherits the matches
made so far. This means that additional matches from the sequence don't
need to be merged into the parent. `push_match` becomes more
complicated, and the current sequence depth needs to be tracked. But
it's a sizeable performance win because it avoids one or more
`push_match` calls on every iteration of a sequence.

The commit also removes `match_hi`, which is no longer necessary.
2022-03-30 10:54:37 +11:00
Nicholas Nethercote
a1b140cdb7 Improve comments and rename many things for consistency.
In particular:
- Replace use of "item" with "matcher position/"mp".
- Replace use of "repetition" with "sequence".
- Replace `ms` with `matcher`.
2022-03-30 10:50:17 +11:00
Nicholas Nethercote
ac3d8ce1c6 Clarify comments about doc comments in macros. 2022-03-30 10:42:47 +11:00
Nicholas Nethercote
2b60cc081b Simplify and rename count_names. 2022-03-30 10:42:34 +11:00
Nicholas Nethercote
df6ead557d Add a useful assertion. 2022-03-29 08:00:26 +11:00
Dylan DPC
1c8b7412d4
Rollup merge of - nnethercote:allow-doc-comments-in-macros, r=petrochenkov
Ignore doc comments in a declarative macro matcher.

Fixes . Reverts to the old behaviour before  introduced a
regression.

r? `@petrochenkov`
2022-03-28 16:08:11 +02:00
Dylan DPC
ae037a86f9
Rollup merge of - nnethercote:rm-NtTT, r=petrochenkov
Remove `Nonterminal::NtTT`.

It's only needed for macro expansion, not as a general element in the
AST. This commit removes it, adds `NtOrTt` for the parser and macro
expansion cases, and renames the variants in `NamedMatch` to better
match the new type.

r? `@petrochenkov`
2022-03-28 16:08:07 +02:00
Nicholas Nethercote
9967594346 Ignore doc comments in a declarative macro matcher.
Fixes . Reverts to the old behaviour before  introduced a
regression.
2022-03-28 10:45:24 +11:00
Nicholas Nethercote
364b908d57 Remove Nonterminal::NtTT.
It's only needed for macro expansion, not as a general element in the
AST. This commit removes it, adds `NtOrTt` for the parser and macro
expansion cases, and renames the variants in `NamedMatch` to better
match the new type.
2022-03-28 10:03:02 +11:00
Dylan DPC
979c8e885e
Rollup merge of - Badel2:resolve-path, r=Dylan-DPC
Move resolve_path to rustc_builtin_macros and make it private

Fixing a FIXME introduced by `@jyn514` in 
2022-03-27 05:36:09 +02:00
David Tolnay
f383134acc
Use str and char's Debug impl to format literals 2022-03-26 13:15:48 -07:00
Badel2
ea26d72710 Move resolve_path to rustc_builtin_macros and make it private 2022-03-26 16:47:13 +01:00
Vadim Petrochenkov
baa3ad4dc8 proc-macro: Stop wrapping ident matchers into groups 2022-03-26 12:38:46 +03:00
bors
c74925438c Auto merge of - cjgillot:once-diag, r=estebank
Remove `Session::one_time_diagnostic`

This is untracked mutable state, which modified the behaviour of queries.
It was used for 2 things: some full-blown errors, but mostly for lint declaration notes ("the lint level is defined here" notes).

It is replaced by the diagnostic deduplication infra which already exists in the diagnostic emitter.
A new diagnostic level `OnceNote` is introduced specifically for lint notes, to deduplicate subdiagnostics.

As a drive-by, diagnostic emission takes a `&mut` to allow dropping the `SubDiagnostic`s.
2022-03-26 00:54:54 +00:00
Nicholas Nethercote
fdec26ddad Shrink MatcherPosRepetition.
Currently it copies a `KleeneOp` and a `Token` out of a
`SequenceRepetition`. It's better to store a reference to the
`SequenceRepetition`, which is now possible due to  having changed
the lifetimes.
2022-03-25 12:35:56 +11:00
Nicholas Nethercote
cad5f1e774 Shrink NamedMatchVec to one inline element.
This counters the `NamedMatchVec` size increase from the previous
commit, leaving `NamedMatchVec` smaller than before.
2022-03-25 12:35:56 +11:00
Nicholas Nethercote
6817442ec7 Split NamedMatch::MatchNonterminal in two.
The `Lrc` is only relevant within `transcribe()`. There, the `Lrc` is
helpful for the non-`NtTT` cases, because the entire nonterminal is
cloned. But for the `NtTT` cases the inner token tree is cloned (a full
clone) and so the `Lrc` is of no help.

This commit splits the `NtTT` and non-`NtTT` cases, avoiding the useless
`Lrc` in the former case, for the following effect on macro-heavy
crates.
- It reduces the total number of allocations a lot.
- It increases the size of some of the remaining allocations.
- It doesn't affect *peak* memory usage, because the larger allocations
  are short-lived.

This overall gives a speed win.
2022-03-25 12:35:52 +11:00
Nicholas Nethercote
904e70a7b0 Add a size assertion for NamedMatchVec. 2022-03-23 13:54:34 +11:00
bors
a4a5e79814 Auto merge of - nnethercote:TtParser, r=petrochenkov
Introduce `TtParser`

These commits make a number of changes to declarative macro expansion, resulting in code that is shorter, simpler, and faster.

Best reviewed one commit at a time.

r? `@petrochenkov`
2022-03-22 21:46:57 +00:00
Nicholas Nethercote
31df680789 Eliminate TokenTreeOrTokenTreeSlice.
As its name suggests, `TokenTreeOrTokenTreeSlice` is either a single
`TokenTree` or a slice of them. It has methods `len` and `get_tt` that
let it be treated much like an ordinary slice. The reason it isn't an
ordinary slice is that for `TokenTree::Delimited` the open and close
delimiters are represented implicitly, and when they are needed they are
constructed on the fly with `Delimited::{open,close}_tt`, rather than
being present in memory.

This commit changes `Delimited` so the open and close delimiters are
represented explicitly. As a result, `TokenTreeOrTokenTreeSlice` is no
longer needed and `MatcherPos` and `MatcherTtFrame` can just use an
ordinary slice. `TokenTree::{len,get_tt}` are also removed, because they
were only needed to support `TokenTreeOrTokenTreeSlice`.

The change makes the code shorter and a little bit faster on benchmarks
that use macro expansion heavily, partly because `MatcherPos` is a lot
smaller (less data to `memcpy`) and partly because ordinary slice
operations are faster than `TokenTreeOrTokenTreeSlice::{len,get_tt}`.
2022-03-23 07:13:31 +11:00
Caio
74e7313e0e Fix generated tokens hygiene 2022-03-21 19:45:55 -03:00
Nicholas Nethercote
754dc8e66f Move items into TtParser as Vecs.
By putting them in `TtParser`, we can reuse them for every rule in a
macro. With that done, they can be `SmallVec` instead of `Vec`, and this
is a performance win because these vectors are hot and `SmallVec`
operations are a bit slower due to always needing an "inline or heap?"
check.
2022-03-21 10:09:24 +11:00
Nicholas Nethercote
cedb787f6e Remove MatcherPosHandle.
This type was a small performance win for `html5ever`, which uses a
macro with hundreds of very simple rules that don't contain any
metavariables. But this type is complicated (extra lifetimes) and
perf-neutral for macros that do have metavariables.

This commit removes `MatcherPosHandle`, simplifying things a lot. This
increases the allocation rate for `html5ever` and similar cases a bit,
but makes things easier for follow-up changes that will improve
performance more than what we lost here.
2022-03-21 10:08:29 +11:00
Camille GILLOT
056951d628 Take &mut Diagnostic in emit_diagnostic.
Taking a Diagnostic by move would break the usual pattern
`diag.label(..).emit()`.
2022-03-20 20:36:08 +01:00
Nicholas Nethercote
10644e0789 Remove an impossible code path.
Doc comments cannot appear in a matcher.
2022-03-19 09:44:47 +11:00
Nicholas Nethercote
39810a85da Add TtParser::macro_name.
Instead of passing it into `parse_tt`.
2022-03-19 09:44:44 +11:00
Nicholas Nethercote
354bd1071c Rename bb_items_ambiguity_error as ambiguity_error.
Because it involves `next_items` as well as `bb_items`.
2022-03-19 08:04:06 +11:00
Nicholas Nethercote
d21b4f30c1 Introduce TtParser.
It currently has no state, just the three methods `parse_tt`,
`parse_tt_inner`, and `bb_items_ambiguity_error`.

This commit is large but trivial, and mostly consists of changes to the
indentation of those methods. Subsequent commits will do more.
2022-03-19 07:47:22 +11:00
bors
a8adf7685a Auto merge of - nnethercote:parse_tt-more-refactoring, r=petrochenkov
Still more refactoring of `parse_tt`

r? `@petrochenkov`
2022-03-18 12:34:05 +00:00
Nicholas Nethercote
440a685575 Rename TtSeq as TtSlice.
It's a better name because (a) it holds a slice, and (b) "sequence" has
other meanings in this file.
2022-03-18 17:47:08 +11:00
Nicholas Nethercote
f43028d06f Tweak a bunch of comments.
I've been staring at these enough lately that they're annoying me, let's
make them better.
2022-03-18 17:22:34 +11:00
Nicholas Nethercote
14875a5564 Reorder cases in parse_tt_inner.
I find the new order easier to read: within a matcher; past the end of a
repetition; at end of input. It also reduces the indentation level by
one for
2022-03-18 14:21:13 +11:00
Nicholas Nethercote
83044714a1 Only modify eof_items if token == Eof.
Because that's the condition under which `eof_items` is used.
2022-03-18 14:11:01 +11:00
Nicholas Nethercote
8bd1bcad58 Factor out some code into MatcherPos::repetition.
Also move `create_matches` within `impl MatcherPos`, because it's only
used within that impl block.
2022-03-18 14:09:02 +11:00
Nicholas Nethercote
5bbbee5ba7 Add two useful assertions. 2022-03-18 13:57:11 +11:00
mark
bb8d4307eb rustc_error: make ErrorReported impossible to construct
There are a few places were we have to construct it, though, and a few
places that are more invasive to change. To do this, we create a
constructor with a long obvious name.
2022-03-16 10:35:24 -05:00
bors
95561b336c Auto merge of - pnkfelix:inject-use-suggestion-sites, r=ekuber
More robust fallback for `use` suggestion

Our old way to suggest where to add `use`s would first look for pre-existing `use`s in the relevant crate/module, and if there are *no* uses, it would fallback on trying to use another item as the basis for the suggestion.

But this was fragile, as illustrated in issue 

This PR instead identifies span of the first token after any inner attributes, and uses *that* as the fallback for the `use` suggestion.

Fix 
2022-03-15 03:56:33 +00:00
Caio
5d333c155e Fix remaining meta-variable expression TODOs 2022-03-14 08:29:20 -03:00
Matthias Krüger
8c87132103
Rollup merge of - c410-f3r:meta-take-2, r=petrochenkov
[2/2] Implement macro meta-variable expression

Final part of https://github.com/rust-lang/rust/pull/93545#issuecomment-1050963295

r? `@petrochenkov`
2022-03-12 09:35:45 +01:00
Caio
d0eca08bc4 Implement macro meta-variable expression 2022-03-11 17:48:51 -03:00
Nicholas Nethercote
95d13fa37d Move a parse_tt error case into a separate function. 2022-03-11 14:10:21 +11:00
Nicholas Nethercote
235a87fbd3 Make next_items a SmallVec.
For consistency, and to make the code slightly nicer.
2022-03-11 14:10:21 +11:00
Nicholas Nethercote
c13ca42d67 Move eof_items handling entirely within inner_parse_loop.
Also rename `inner_parse_loop` as `parse_tt_inner`, because it's no
longer just a loop.
2022-03-11 14:10:21 +11:00
Nicholas Nethercote
9f0798b2eb Add a useful assertion. 2022-03-11 14:10:21 +11:00
Nicholas Nethercote
4d4baf7c9a Disallow TokenTree::{MetaVar,MetaVarExpr} in matchers.
They should only appear in transcribers.
2022-03-11 14:10:19 +11:00
Nicholas Nethercote
09c3e82050 Refactor the second half of parse_tt.
The current structure makes it hard to tell that there are just four
distinct code paths, depending on how many items there are in `bb_items`
and `next_items`. This commit introduces a `match` that clarifies
things.
2022-03-11 13:56:54 +11:00
Caio
8073a88f35 Implement macro meta-variable expressions 2022-03-09 16:46:23 -03:00
bors
65f6d33b77 Auto merge of - cjgillot:ensure-stability, r=lcnr
Ensure stability directives are checked in all cases

Split off  

Stability and deprecation were not checked in all cases, for instance if a type error happened.
This PR moves the check earlier in the pipeline to ensure the errors are emitted in all cases.

r? `@lcnr`
2022-03-04 05:49:14 +00:00
Felix S. Klock II
b82795244e Associate multiple with a crate too. 2022-03-03 18:45:25 -05:00
Felix S. Klock II
e9035f7bef refactor: prepare to associate multiple spans with a module. 2022-03-03 14:38:50 -05:00
Matthias Krüger
939c1585a4
Rollup merge of - cuishuang:master, r=oli-obk
all: fix some typos

Signed-off-by: cuishuang <imcusg@gmail.com>
2022-03-03 20:01:48 +01:00
Matthias Krüger
26cbf9158d
Rollup merge of - Urgau:stmt-node-id-ice, r=petrochenkov
Fix invalid lint_node_id being put on a removed stmt

This pull-request remove a invalid `assign_id!` being put on an stmt node.

The problem is that this node is being removed away by a cfg making it unreachable when triggering a buffered lint.
The comment in the other match arm already tell to not assign a id because it could have a `#[cfg()]` so this is just respecting the comment.

Fixes https://github.com/rust-lang/rust/issues/94523
r? ```````@petrochenkov```````
2022-03-03 20:01:48 +01:00
Matthias Krüger
16c6594f34
Rollup merge of - nnethercote:parse_tt-cleanups, r=petrochenkov
`parse_tt` cleanups

I've been looking closely at this code, and saw some opportunities to improve its readability.

r? ```````@petrochenkov```````
2022-03-03 20:01:45 +01:00
Camille GILLOT
fbcf7d415b Move the set of features to the features query. 2022-03-03 18:08:30 +01:00
cuishuang
00fffdddd2 all: fix some typos
Signed-off-by: cuishuang <imcusg@gmail.com>
2022-03-03 19:47:23 +08:00
Loïc BRANSTETT
516488484e Fix invalid lint_node_id being put on a removed stmt 2022-03-03 11:52:09 +01:00
Nicholas Nethercote
97eb1b4669 Change initial_matcher_pos() into MatcherPos::new(). 2022-03-03 21:47:02 +11:00
Nicholas Nethercote
e5f3fd6250 Use a better return type for inner_parse_loop.
Because `inner_parse_loop` has only one way to not succeed, not three.
2022-03-03 21:46:59 +11:00
Nicholas Nethercote
643ba50004 Introduce MatcherPosRepetition.
There are three `Option` fields in `MatcherPos` that are only used in
tandem. This commit combines them, making the code slightly easier to
read. (It also makes clear that the `sep` field arguably should have
been `Option<Option<Token>>`!)
2022-03-03 21:45:52 +11:00
Nicholas Nethercote
b9fabc3f9c Add a static size assertion for MatcherPos. 2022-03-03 21:45:45 +11:00
Nicholas Nethercote
11c565f14b Improve if/else formatting in macro_parser.rs.
To avoid the strange style where comments force `else` onto its own
line.

The commit also removes several else-after-return constructs, which can
be hard to read.
2022-03-03 21:45:42 +11:00
Matthias Krüger
88aa75ba8e
Rollup merge of - mark-i-m:macro-comments, r=petrochenkov
Add some examples to comments in mbe code

I found these things non-obvious when re-familiarizing myself with the code.

r? `@petrochenkov`
2022-03-03 11:02:56 +01:00
mark
88b99224c1 add some examples to comments in mbe code 2022-03-02 21:33:43 -06:00
Dylan DPC
493ed7a6af
Rollup merge of - Urgau:check-cfg-allowness, r=petrochenkov
Improve allowness of the unexpected_cfgs lint

This pull-request improve the allowness (`#[allow(...)]`) of the `unexpected_cfgs` lint.

Before this PR only crate level `#![allow(unexpected_cfgs)]` worked, now with this PR it also work when put around `cfg!` or if it is in a upper level. Making it work ~for the attributes `cfg`, `cfg_attr`, ...~ for the same level is awkward as the current code is design to give "Some parent node that is close to this macro call" (cf. https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/base/struct.ExpansionData.html) meaning that allow on the same line as an attribute won't work. I'm note even sure if this would be possible.

Found while working on https://github.com/rust-lang/rust/pull/94298.
r? ````````@petrochenkov````````
2022-03-03 01:09:12 +01:00
mark
e489a94dee rename ErrorReported -> ErrorGuaranteed 2022-03-02 09:45:25 -06:00
Loïc BRANSTETT
765205b9b8 Improve allowness of the unexpected_cfgs lint 2022-03-01 14:29:12 +01:00
Esteban Kuber
f42b4f595e Tweak diagnostics
* Recover from invalid `'label: ` before block.
* Make suggestion to enclose statements in a block multipart.
* Point at `match`, `while`, `loop` and `unsafe` keywords when failing
  to parse their expression.
* Do not suggest `{ ; }`.
* Do not suggest `|` when very unlikely to be what was wanted (in `let`
  statements).
2022-02-28 18:22:45 +00:00
Mark Rousskov
22c3a71de1 Switch bootstrap cfgs 2022-02-25 08:00:52 -05:00
Matthias Krüger
6ec5b056b0
Rollup merge of - yanganto:ignore-message, r=Mark-Simulacrum
Provide ignore message in the result of test

Provide ignore the message in the result of the test.

This PR does not need RFC, because it is about the presentation of the report of `cargo test`.

However, the following document listed here helps you to know about PR.

- [RFC](https://github.com/rust-lang/rfcs/pull/3217)
- [Rendered](https://github.com/yanganto/rfcs/blob/ignore-test-message/text/0000-ignore-test-message.md)
- [Previous discussion on IRLO](https://internals.rust-lang.org/t/pre-rfc-provide-ignore-message-when-the-test-ignored/15904)

If there is something improper, please let me know.
Thanks.
2022-02-25 07:30:47 +01:00
Antonio Yang
bb3b5574cd Include ignore message in libtest output
As an example:

    #[test]
    #[ignore = "not yet implemented"]
    fn test_ignored() {
        ...
    }

Will now render as:

    running 2 tests
    test tests::test_ignored ... ignored, not yet implemented

    test result: ok. 1 passed; 0 failed; 1 ignored; 0 measured; 0 filtered out; finished in 0.00s
2022-02-24 17:36:36 -05:00
Eduard-Mihai Burtescu
b7e95dee65 rustc_errors: let DiagnosticBuilder::emit return a "guarantee of emission". 2022-02-23 06:38:52 +00:00
Eduard-Mihai Burtescu
0b9d70cf6d rustc_errors: take self by value in DiagnosticBuilder::cancel. 2022-02-23 06:08:06 +00:00
Eduard-Mihai Burtescu
02ff9e0aef Replace &mut DiagnosticBuilder, in signatures, with &mut Diagnostic. 2022-02-23 05:38:19 +00:00
Matthias Krüger
f2d6770f77
Rollup merge of - est31:let_else, r=cjgillot
Adopt let else in more places

Continuation of , , , , , .

I have extended my clippy lint to also recognize tuple passing and match statements. The diff caused by fixing it is way above 1 thousand lines. Thus, I split it up into multiple pull requests to make reviewing easier. This is the biggest of these PRs and handles the changes outside of rustdoc, rustc_typeck, rustc_const_eval, rustc_trait_selection, which were handled in PRs , , , .
2022-02-20 00:37:34 +01:00
est31
2ef8af6619 Adopt let else in more places 2022-02-19 17:27:43 +01:00
Matthias Krüger
b80057d08d compiler: clippy::complexity fixes
useless_format
map_flatten
useless_conversion
needless_bool
filter_next
clone_on_copy
needless_option_as_deref
2022-02-03 23:16:03 +01:00
lcnr
a1a30f7548 add a rustc::query_stability lint 2022-02-01 10:15:59 +01:00
Eric Huss
0610d4fa66
Rollup merge of - pietroalbini:pa-bootstrap-update, r=Mark-Simulacrum
Bootstrap compiler update

r? ``@Mark-Simulacrum``
2022-01-30 08:37:46 -08:00
Pietro Albini
5b3462c556
update cfg(bootstrap)s 2022-01-28 15:01:07 +01:00
Vadim Petrochenkov
67cccaff48 expand: Pass everything by reference to pre-expansion lint callback 2022-01-23 19:31:32 +08:00
Vadim Petrochenkov
05cd75504b rustc_lint: Stop creating a fake ast::Crate for running early lints
Add a trait generalizing over the crate root and freshly loaded modules instead
This also makes node IDs used for pre-expansion linting more precise
2022-01-23 19:31:32 +08:00
Vadim Petrochenkov
51b2338611 rustc_lint: Reuse the set of registered tools from resolver 2022-01-23 18:51:51 +08:00
bors
fd20513f52 Auto merge of - petrochenkov:ltrattr2, r=Aaron1011
expand: Pick `cfg`s and `cfg_attrs` one by one, like other attributes

This is a rebase of https://github.com/rust-lang/rust/pull/83354, but without any language-changing parts ~(except for https://github.com/rust-lang/rust/pull/84110)~, i.e. the attribute expansion order is the same.

This is a pre-requisite for any other changes making cfg attributes closer to regular macro attributes
- Possibly changing their expansion order (https://github.com/rust-lang/rust/issues/83331)
- Keeping macro backtraces for cfg attributes, or otherwise making them visible after expansion without keeping them in place literally (https://github.com/rust-lang/rust/pull/84110).

Two exceptions to the "one by one" behavior are:
- cfgs eagerly expanded by `derive` and `cfg_eval`, they are still expanded in a batch, that's by design.
- cfgs at the crate root, they are currently expanded not during the main expansion pass, but before that, during `#![feature]` collection. I'll try to disentangle that logic later in a separate PR.

r? `@Aaron1011`
2022-01-17 02:06:54 +00:00
bors
2e2c86eba2 Auto merge of - rukai:replace_vec_into_iter_with_array_into_iter, r=Mark-Simulacrum
Replace usages of vec![].into_iter with [].into_iter

`[].into_iter` is idiomatic over `vec![].into_iter` because its simpler and faster (unless the vec is optimized away in which case it would be the same)

So we should change all the implementation, documentation and tests to use it.

I skipped:
* `src/tools` - Those are copied in from upstream
* `src/test/ui` - Hard to tell if `vec![].into_iter` was used intentionally or not here and not much benefit to changing it.
*  any case where `vec![].into_iter` was used because we specifically needed a `Vec::IntoIter<T>`
*  any case where it looked like we were intentionally using `vec![].into_iter` to test it.
2022-01-11 14:23:24 +00:00
Vadim Petrochenkov
e87ce7ad74 expand: Pick cfgs and cfg_attrs one by one, like other attributes 2022-01-10 18:11:44 +08:00
Lucas Kent
08829853d3 eplace usages of vec![].into_iter with [].into_iter 2022-01-09 14:09:25 +11:00
Vadim Petrochenkov
4523466770 expand: Import more AST enums 2022-01-07 14:54:16 +08:00
Vadim Petrochenkov
800ba8f8e8 expand: Refactor InvocationCollector visitor for better code reuse 2022-01-07 14:41:22 +08:00
Vadim Petrochenkov
4fd23350cd expand: Remove some unnecessary self mutability 2022-01-07 13:50:03 +08:00
Vadim Petrochenkov
dc7e771155 expand: Rename some AstFragments to match AST structures 2022-01-07 13:50:03 +08:00
Vadim Petrochenkov
55595c5616 ast: Always keep a NodeId in ast::Crate
This makes it more uniform with other expanded nodes
2022-01-05 17:09:37 +08:00
Matthias Krüger
b9f7197ab3
Rollup merge of - petrochenkov:cratexp2, r=Aaron1011
ast: Avoid aborts on fatal errors thrown from mutable AST visitor

Set the node to some dummy value and rethrow the error instead.

When using the old aborting `visit_clobber` in `InvocationCollector::visit_crate` the next tests abort due to fatal errors:
```
ui\modules\path-invalid-form.rs
ui\modules\path-macro.rs
ui\modules\path-no-file-name.rs
ui\parser\issues\issue-5806.rs
ui\parser\mod_file_with_path_attr.rs
```

Follow up to https://github.com/rust-lang/rust/pull/91313.
2021-12-30 13:12:33 +01:00
bors
a41a6925ba Auto merge of - nnethercote:rm-SymbolStr, r=oli-obk
Remove `SymbolStr`

This was originally proposed in https://github.com/rust-lang/rust/pull/74554#discussion_r466203544. As well as removing the icky `SymbolStr` type, it allows the removal of a lot of `&` and `*` occurrences.

Best reviewed one commit at a time.

r? `@oli-obk`
2021-12-19 09:31:37 +00:00
Matthias Krüger
d258e92900
Rollup merge of - jhpratt:stabilize-destructuring_assignment, r=jackh726,pnkfelix
Stabilize `destructuring_assignment`

Closes 

- [Stabilization report](https://github.com/rust-lang/rust/issues/71126#issuecomment-941148058)
- [Completed FCP](https://github.com/rust-lang/rust/issues/71126#issuecomment-954914819)

`@rustbot` label +F-destructuring-assignment +T-lang
Also needs +relnotes but I don't have permission to add that tag.
2021-12-15 08:36:19 +01:00
Nicholas Nethercote
b1c934ebb8 Remove unnecessary sigils around Ident::as_str() calls. 2021-12-15 17:32:42 +11:00
Nicholas Nethercote
056d48a2c9 Remove unnecessary sigils around Symbol::as_str() calls. 2021-12-15 17:32:14 +11:00
Jacob Pratt
d95f749f14
Stabilize destructuring_assignment 2021-12-14 22:38:51 -05:00
Nicholas Nethercote
8cddcd39ba Remove SymbolStr.
By changing `as_str()` to take `&self` instead of `self`, we can just
return `&str`. We're still lying about lifetimes, but it's a smaller lie
than before, where `SymbolStr` contained a (fake) `&'static str`!
2021-12-15 13:30:26 +11:00
PFPoitras
304ede6bcc Stabilize iter::zip. 2021-12-14 18:50:31 -04:00
est31
15de4cbc4b Remove redundant [..]s 2021-12-09 00:01:29 +01:00
bjorn3
9b6c510905 Future compatibility warning on cfg_attr on crate_type and crate_name 2021-12-07 11:47:21 -05:00
Mara Bos
1acb44f03c Use IntoIterator for array impl everywhere. 2021-12-04 19:40:33 +01:00
Vadim Petrochenkov
bdb851f567 ast: Avoid aborts on fatal errors thrown from mutable AST visitor
Set the node to some dummy value and rethwor the error instead.
2021-12-04 18:51:16 +08:00
Matthias Krüger
2b64476b9c
Rollup merge of - ecstatic-morse:pat-param-spec-suggest, r=estebank
Suggest the `pat_param` specifier before `|` on 2021 edition

Ran into this today after writing some Rust for the first time in a while.

r? `@estebank`
2021-12-04 02:26:23 +01:00
Matthias Krüger
d96ce3ea8e
Rollup merge of - Mark-Simulacrum:bump-stage0, r=pietroalbini
Bump stage0 compiler

r? `@pietroalbini` (or anyone else)
2021-12-02 15:52:03 +01:00
Mark Rousskov
971c549ca3 re-format with new rustfmt 2021-11-30 13:08:41 -05:00
Mark Rousskov
b221c877e8 Apply cfg-bootstrap switch 2021-11-30 10:51:42 -05:00
Dylan MacKenzie
f6b499da16 Suggest the pat_param specifier before | on 2021 edition
We have a migration warning but no lint for users who have enabled the
new edition.
2021-11-29 22:20:34 -08:00
Vadim Petrochenkov
141c6cc78e expand: Turn ast::Crate into a first class expansion target
And stop creating a fake `mod` item for the crate root when expanding a crate.
2021-11-28 15:48:55 +08:00
Josh Triplett
8c9bfaa5f3 Stabilize format_args_capture
Works as expected, and there are widespread reports of success with it,
as well as interest in it.
2021-11-15 10:14:29 +01:00
Nika Layzell
3e4d3d2a29 proc_macro: Add an expand_expr method to TokenStream
This feature is aimed at giving proc macros access to powers similar to
those used by builtin macros such as `format_args!` or `concat!`. These
macros are able to accept macros in place of string literal parameters,
such as the format string, as they perform recursive macro expansion
while being expanded.

This can be especially useful in many cases thanks to helper macros like
`concat!`, `stringify!` and `include_str!` which are often used to
construct string literals at compile-time in user code.

For now, this method only allows expanding macros which produce
literals, although more expresisons will be supported before the method
is stabilized.
2021-11-12 15:41:40 -05:00
Joshua Nelson
0ac13bd430 Don't abort compilation after giving a lint error
The only reason to use `abort_if_errors` is when the program is so broken that either:
1. later passes get confused and ICE
2. any diagnostics from later passes would be noise

This is never the case for lints, because the compiler has to be able to deal with `allow`-ed lints.
So it can continue to lint and compile even if there are lint errors.
2021-11-08 01:22:28 +00:00
Mark Rousskov
3215eeb99f
Revert "Add rustc lint, warning when iterating over hashmaps" 2021-10-28 11:01:42 -04:00
Matthias Krüger
87822b27ee
Rollup merge of - lcnr:query-stable-lint, r=estebank
Add rustc lint, warning when iterating over hashmaps

r? rust-lang/wg-incr-comp
2021-10-24 15:48:42 +02:00
Yuki Okushi
cbebdd8e67
Rollup merge of - petrochenkov:visitok2, r=jackh726
rustc_ast: Turn `MutVisitor::token_visiting_enabled` into a constant

It's a visitor property rather than something that needs to be determined at runtime
2021-10-22 19:42:48 +09:00
bors
1af55d19c7 Auto merge of - est31:let_else, r=michaelwoerister
Adopt let_else across the compiler

This performs a substitution of code following the pattern:

```
let <id> = if let <pat> = ... { identity } else { ... : ! };
```

To simplify it to:

```
let <pat> = ... { identity } else { ... : ! };
```

By adopting the `let_else` feature (cc ).

The PR also updates the syn crate because the currently used version of the crate doesn't support `let_else` syntax yet.

Note: Generally I'm the person who *removes* usages of unstable features from the compiler, not adds more usages of them, but in this instance I think it hopefully helps the feature get stabilized sooner and in a better state. I have written a [comment](https://github.com/rust-lang/rust/issues/87335#issuecomment-944846205) on the tracking issue about my experience and what I feel could be improved before stabilization of `let_else`.
2021-10-19 14:41:39 +00:00
Vadim Petrochenkov
d2470e74e1 rustc_ast: Turn MutVisitor::token_visiting_enabled into a constant
It's a visitor property rather than something that needs to be determined at runtime
2021-10-18 00:23:24 +03:00
Vadim Petrochenkov
a6808335d4 rustc_span: Ident::invalid -> Ident::empty
The equivalent for `Symbol`s was renamed some time ago (`kw::Invalid` -> `kw::Empty`), and it makes sense to do the same thing for `Ident`s.
2021-10-17 23:20:30 +03:00
Yuki Okushi
b8173c59c6
Rollup merge of - matthiaskrgr:clpcompl, r=oli-obk
clippy::complexity fixes
2021-10-17 07:52:20 +09:00
Matthias Krüger
c645d3f3b9 clippy::complexity changes 2021-10-16 18:11:16 +02:00
est31
1418df5888 Adopt let_else across the compiler
This performs a substitution of code following the pattern:

let <id> = if let <pat> = ... { identity } else { ... : ! };

To simplify it to:

let <pat> = ... { identity } else { ... : ! };

By adopting the let_else feature.
2021-10-16 07:18:05 +02:00
lcnr
00e5abe9b6 allow potential_query_instability everywhere 2021-10-15 10:58:18 +02:00
Cameron Steffen
1333ae67f4 Remove trailing semicolon from macro call span 2021-10-15 02:24:48 -05:00
Cameron Steffen
c75a734a43 Remove redundant matching 2021-10-15 02:24:48 -05:00
Ross MacArthur
d2613fb7a5
Improve help for recursion limit errors 2021-09-28 22:17:13 +02:00
Eric Huss
75f058dbfd Check for macros in built-in attributes that don't support them. 2021-09-25 09:03:15 -07:00
bjorn3
9886c233d8 Remove Symbol::len
It is used exactly once and can be replaced with the equally fast
.as_str().len()
2021-09-22 13:37:09 +02:00
Mark Rousskov
c746be2219 Migrate to 2021 2021-09-20 22:21:42 -04:00
Yuki Okushi
1c3fce01df
Rollup merge of - Aaron1011:trailing-macro-semi, r=petrochenkov
Fix linting when trailing macro expands to a trailing semi

When a macro is used in the trailing expression position of a block
(e.g. `fn foo() { my_macro!() }`), we currently parse it as an
expression, rather than a statement. As a result, we ended up
using the `NodeId` of the containing statement as our `lint_node_id`,
even though we don't normally do this for macro calls.

If such a macro expands to an expression with a `#[cfg]` attribute,
then the trailing statement can get removed entirely. This lead to
an ICE, since we were usng the `NodeId` of the expression to emit
a lint.

Ths commit makes us skip updating `lint_node_id` when handling
a macro in trailing expression position. This will cause us to
lint at the closest parent of the macro call.
2021-09-19 17:31:31 +09:00
Aaron Hill
bd4c9676c7
Fix linting when trailing macro expands to a trailing semi
When a macro is used in the trailing expression position of a block
(e.g. `fn foo() { my_macro!() }`), we currently parse it as an
expression, rather than a statement. As a result, we ended up
using the `NodeId` of the containing statement as our `lint_node_id`,
even though we don't normally do this for macro calls.

If such a macro expands to an expression with a `#[cfg]` attribute,
then the trailing statement can get removed entirely. This lead to
an ICE, since we were usng the `NodeId` of the expression to emit
a lint.

Ths commit makes us skip updating `lint_node_id` when handling
a macro in trailing expression position. This will cause us to
lint at the closest parent of the macro call.
2021-09-15 19:36:28 -05:00
Michael Howell
ef44452a83 chore(rustc_expand): fix typo in comment 2021-09-15 09:13:18 -07:00
bors
547d9374d2 Auto merge of - cjgillot:resolve-span, r=michaelwoerister,petrochenkov
Encode spans relative to the enclosing item

The aim of this PR is to avoid recomputing queries when code is moved without modification.

MCP at https://github.com/rust-lang/compiler-team/issues/443

This is achieved by :
1. storing the HIR owner LocalDefId information inside the span;
2. encoding and decoding spans relative to the enclosing item in the incremental on-disk cache;
3. marking a dependency to the `source_span(LocalDefId)` query when we translate a span from the short (`Span`) representation to its explicit (`SpanData`) representation.

Since all client code uses `Span`, step 3 ensures that all manipulations
of span byte positions actually create the dependency edge between
the caller and the `source_span(LocalDefId)`.
This query return the actual absolute span of the parent item.
As a consequence, any source code motion that changes the absolute byte position of a node will either:
- modify the distance to the parent's beginning, so change the relative span's hash;
- dirty `source_span`, and trigger the incremental recomputation of all code that
  depends on the span's absolute byte position.

With this scheme, I believe the dependency tracking to be accurate.

For the moment, the spans are marked during lowering.
I'd rather do this during def-collection,
but the AST MutVisitor is not practical enough just yet.
The only difference is that we attach macro-expanded spans
to their expansion point instead of the macro itself.
2021-09-11 23:35:28 +00:00
Camille GILLOT
2e37ed87fc Record call_site parent for macros. 2021-09-10 20:19:25 +02:00
Camille GILLOT
00485e0c0e Keep a parent LocalDefId in SpanData. 2021-09-10 20:17:33 +02:00
Manish Goregaokar
358a018292
Rollup merge of - ibraheemdev:i-86865, r=cjgillot
Emit suggestion when passing byte literal to format macro

Closes 
2021-09-10 08:23:15 -07:00
Manish Goregaokar
000dbd27f1
Rollup merge of - m-ou-se:proc-macro-span-shrink, r=dtolnay
Add proc_macro::Span::{before, after}.

This adds `proc_macro::Span::before()` and `proc_macro::Span::after()` to get a zero width span at the start or end of the span.

These are equivalent to rustc's `Span::shrink_to_lo()` and `Span::shrink_to_hi()` but with a less cryptic name. They are useful when generating diagnostlics like "missing \<thing\> after \<thing\>".

E.g.

```rust
syn::Error::new(ident.span().after(), "missing `:` after field name").into_compile_error()
```
2021-09-10 08:23:14 -07:00
Mark Rousskov
b4e7649d6d Bump stage0 compiler to 1.56 2021-09-08 20:51:05 -04:00
bors
b4e8596e3e Auto merge of - estebank:type-ascription-can-die-in-a-fire, r=wesleywiser
Detect bare blocks with type ascription that were meant to be a `struct` literal

Address part of .

Potential improvement: silence the other knock down errors in `issue-34255-1.rs`.
2021-09-04 01:40:36 +00:00
bors
577a76f003 Auto merge of - cjgillot:lower-global, r=petrochenkov
Move global analyses from lowering to resolution

Split off https://github.com/rust-lang/rust/pull/87234

r? `@petrochenkov`
2021-09-03 14:47:13 +00:00
Esteban Kuber
12ce6e9c60 Detect bare blocks with type ascription that were meant to be a struct literal
Address part of .

Potential improvement: silence the other knock down errors in
`issue-34255-1.rs`.
2021-09-03 14:43:04 +00:00
bors
fbdff7fae9 Auto merge of - petrochenkov:stmtid, r=Aaron1011
expand: Treat more macro calls as statement macro calls

This PR implements the suggestion from https://github.com/rust-lang/rust/pull/87981#issuecomment-906641052 and treats fn-like macro calls inside `StmtKind::Item` and `StmtKind::Semi` as statement macro calls, which is consistent with treatment of attribute invocations in the same positions and with token-based macro expansion model in general.

This also allows to remove a special case in `NodeId` assignment (previously tried in ), and to use statement `NodeId`s for linting (`assign_id!`).

r? `@Aaron1011`
2021-09-03 06:10:27 +00:00
bors
97f2698484 Auto merge of - michaelwoerister:remapped-diagnostics, r=estebank
Path remapping: Make behavior of diagnostics output dependent on presence of --remap-path-prefix.

This PR fixes a regression () with `--remap-path-prefix` where the flag stopped causing diagnostic messages to be remapped as well. The regression was introduced in https://github.com/rust-lang/rust/pull/83813 where we erroneously assumed that remapping of diagnostic messages was not desired anymore (because  partially undid that functionality with nobody objecting).

The issue is fixed by making `--remap-path-prefix` remap diagnostic messages again, including for paths that have been remapped in upstream crates (e.g. the standard library). This means that "sysroot-localization" (implemented in ) is also disabled if `rustc` is invoked with `--remap-path-prefix`. The assumption is that once someone starts explicitly remapping paths they also don't want paths to their local Rust installation in their build output.

In the future we might want to give more fine-grained control over this behavior via compiler flags (see https://github.com/rust-lang/rfcs/pull/3127 for a related RFC). For now this PR is intended as a regression fix.

This PR is an alternative to https://github.com/rust-lang/rust/pull/88191, which makes diagnostic messages be remapped unconditionally. That approach, however, would effectively revert .

Fixes https://github.com/rust-lang/rust/issues/87745.

cc `@cbeuw`
r? `@ghost`
2021-09-03 00:23:10 +00:00
Vadim Petrochenkov
9940758416 expand: Treat more macro calls as statement macro calls 2021-09-02 14:14:38 +03:00
Camille GILLOT
f8efe5d822 Compute proc_macros in resolutions. 2021-09-01 20:13:16 +02:00
ibraheemdev
f56034ec3e emit suggestion byte literal is passed to format! 2021-08-31 17:29:42 -04:00
Cameron Steffen
89d2600d01 Add let-else to AST 2021-08-30 20:17:45 -05:00
bors
ae0b03bc6b Auto merge of - klensy:pprust-cow, r=nagisa
Cow'ify some pprust methods

Reduce number of potential needless de/allocations by using `Cow<'static, str>` instead of explicit `String` type.
2021-08-29 17:46:29 +00:00
Michael Woerister
af1b65cb18 Path remapping: Make behavior of diagnostics output dependent on presence of --remap-path-prefix. 2021-08-27 11:50:44 +02:00
Léo Lanteri Thauvin
2b0c8fff8a Various pattern cleanups 2021-08-25 20:24:39 +02:00
Léo Lanteri Thauvin
fde1b76b4b Use if-let guards in the codebase 2021-08-25 20:24:35 +02:00
klensy
c565339c37 Convert some functions to return Cow<'static,str> instead of String to reduce potential reallocations 2021-08-25 00:24:44 +03:00
Aaron Hill
17aef21b30
Remove NonMacroAttr.mark_used 2021-08-21 13:27:29 -05:00
Aaron Hill
af46699f81
Remove Session.used_attrs and move logic to CheckAttrVisitor
Instead of updating global state to mark attributes as used,
we now explicitly emit a warning when an attribute is used in
an unsupported position. As a side effect, we are to emit more
detailed warning messages (instead of just a generic "unused" message).

`Session.check_name` is removed, since its only purpose was to mark
the attribute as used. All of the callers are modified to use
`Attribute.has_name`

Additionally, `AttributeType::AssumedUsed` is removed - an 'assumed
used' attribute is implemented by simply not performing any checks
in `CheckAttrVisitor` for a particular attribute.

We no longer emit unused attribute warnings for the `#[rustc_dummy]`
attribute - it's an internal attribute used for tests, so it doesn't
mark sense to treat it as 'unused'.

With this commit, a large source of global untracked state is removed.
2021-08-21 13:27:27 -05:00
Caio
6aa9937a76 Introduce hir::ExprKind::Let - Take 2 2021-08-15 16:18:26 -03:00
Aaron Hill
cfc3fee952
Revert "Rollup merge of - Aaron1011:stmt-ast-id, r=petrochenkov"
Fixes 

This change interacts badly with `noop_flat_map_stmt`,
which synthesizes multiple statements with the same `NodeId`.

I'm working on a better fix that will still allow us to
remove this special case. For now, let's revert the change
to fix the ICE.

This reverts commit a4262cc984, reversing
changes made to 8ee962f88e.
2021-08-12 08:24:22 -05:00
Aaron Hill
a35d7f2bb3
Remove special case for statement NodeId assignment
We now let `noop_flat_map_stmt` assign `NodeId`s (via `visit_id`),
just as we do for other AST nodes.
2021-08-06 09:30:47 -05:00
David Tolnay
3744dc8687
Remove space after negative sign in Literal to_string 2021-08-03 10:40:52 -07:00
bors
e91405b9d5 Auto merge of - dtolnay:negative, r=Aaron1011
Support negative numbers in Literal::from_str

proc_macro::Literal has allowed negative numbers in a single literal token ever since Rust 1.29, using https://doc.rust-lang.org/stable/proc_macro/struct.Literal.html#method.isize_unsuffixed and similar constructors.

```rust
let lit = proc_macro::Literal::isize_unsuffixed(-10);
```

However, the suite of constructors on Literal is not sufficient for all use cases, for example arbitrary precision floats, or custom suffixes in FFI macros.

```rust
let lit = proc_macro::Literal::f64_unsuffixed(0.101001000100001000001000000100000001); // :(
let lit = proc_macro::Literal::i???_suffixed(10ulong); // :(
```

For those, macros construct the literal using from_str instead, which preserves arbitrary precision, custom suffixes, base, and digit grouping.

```rust
let lit = "0.101001000100001000001000000100000001".parse::<Literal>().unwrap();
let lit = "10ulong".parse::<Literal>().unwrap();
let lit = "0b1000_0100_0010_0001".parse::<Literal>().unwrap();
```

However, until this PR it was not possible to construct a literal token that is **both** negative **and** preserving of arbitrary precision etc.

This PR fixes `Literal::from_str` to recognize negative integer and float literals.
2021-08-03 04:50:28 +00:00
bors
b53a93db2d Auto merge of - lf-:authors, r=Mark-Simulacrum
rfc3052 followup: Remove authors field from Cargo manifests

Since RFC 3052 soft deprecated the authors field, hiding it from
crates.io, docs.rs, and making Cargo not add it by default, and it is
not generally up to date/useful information for contributors, we may as well
remove it from crates in this repo.
2021-08-02 05:49:17 +00:00
bors
aadd6189ad Auto merge of - matthiaskrgr:clippyy_v2, r=nagisa
more clippy::complexity fixes

(also a couple of clippy::perf fixes)
2021-08-01 09:15:15 +00:00
Jade
3cf820e17d rfc3052: Remove authors field from Cargo manifests
Since RFC 3052 soft deprecated the authors field anyway, hiding it from
crates.io, docs.rs, and making Cargo not add it by default, and it is
not generally up to date/useful information, we should remove it from
crates in this repo.
2021-07-29 14:56:05 -07:00
Aaron Hill
cf167c9c9c
Only emit lint for local macros 2021-07-27 14:18:46 -05:00
Matthias Krüger
d709e6efef clippy::single_char_pattern 2021-07-25 12:25:26 +02:00
bors
71a6c7c803 Auto merge of - Aaron1011:note-semi-trailing-macro, r=petrochenkov
Display an extra note for trailing semicolon lint with trailing macro

Currently, we parse macros at the end of a block
(e.g. `fn foo() { my_macro!() }`) as expressions, rather than
statements. This means that a macro invoked in this position
cannot expand to items or semicolon-terminated expressions.

In the future, we might want to start parsing these kinds of macros
as statements. This would make expansion more 'token-based'
(i.e. macro expansion behaves (almost) as if you just textually
replaced the macro invocation with its output). However,
this is a breaking change (see PR ), so it will require
further discussion.

Since the current behavior will not be changing any time soon,
we need to address the interaction with the
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` lint. Since we are parsing
the result of macro expansion as an expression, we will emit a lint
if there's a trailing semicolon in the macro output. However, this
results in a somewhat confusing message for users, since it visually
looks like there should be no problem with having a semicolon
at the end of a block
(e.g. `fn foo() { my_macro!() }` => `fn foo() { produced_expr; }`)

To help reduce confusion, this commit adds a note explaining
that the macro is being interpreted as an expression. Additionally,
we suggest adding a semicolon after the macro *invocation* - this
will cause us to parse the macro call as a statement. We do *not*
use a structured suggestion for this, since the user may actually
want to remove the semicolon from the macro definition (allowing
the block to evaluate to the expression produced by the macro).
2021-07-25 04:34:58 +00:00
Manish Goregaokar
c673d3fed0
Rollup merge of - Aaron1011:expand-known-attrs, r=wesleywiser
Rename `known_attrs` to `expanded_inert_attrs` and move to rustc_expand

There's no need for this to be (untracked) global state.
2021-07-24 09:51:59 -07:00
Aaron Hill
0df5ac8269
Display an extra note for trailing semicolon lint with trailing macro
Currently, we parse macros at the end of a block
(e.g. `fn foo() { my_macro!() }`) as expressions, rather than
statements. This means that a macro invoked in this position
cannot expand to items or semicolon-terminated expressions.

In the future, we might want to start parsing these kinds of macros
as statements. This would make expansion more 'token-based'
(i.e. macro expansion behaves (almost) as if you just textually
replaced the macro invocation with its output). However,
this is a breaking change (see PR ), so it will require
further discussion.

Since the current behavior will not be changing any time soon,
we need to address the interaction with the
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` lint. Since we are parsing
the result of macro expansion as an expression, we will emit a lint
if there's a trailing semicolon in the macro output. However, this
results in a somewhat confusing message for users, since it visually
looks like there should be no problem with having a semicolon
at the end of a block
(e.g. `fn foo() { my_macro!() }` => `fn foo() { produced_expr; }`)

To help reduce confusion, this commit adds a note explaining
that the macro is being interpreted as an expression. Additionally,
we suggest adding a semicolon after the macro *invocation* - this
will cause us to parse the macro call as a statement. We do *not*
use a structured suggestion for this, since the user may actually
want to remove the semicolon from the macro definition (allowing
the block to evaluate to the expression produced by the macro).
2021-07-24 11:46:44 -05:00
Aaron Hill
a2ae191295
Rename known_attrs to expanded_inert_attrs and move to rustc_expand
There's no need for this to be (untracked) global state.
2021-07-23 17:03:07 -05:00
Aaron Hill
070df9e676
Warn on inert attributes used on bang macro invocation
These attributes are currently discarded.
This may change in the future (see ), but for now,
placing inert attributes on a macro invocation does nothing,
so we should warn users about it.

Technically, it's possible for there to be attribute macro
on the same macro invocation (or at a higher scope), which
inspects the inert attribute. For example:

```rust
#[look_for_inline_attr]
#[inline]
my_macro!()

#[look_for_nested_inline]
mod foo { #[inline] my_macro!() }
```

However, this would be a very strange thing to do.
Anyone running into this can manually suppress the warning.
2021-07-19 17:49:28 -05:00
David Tolnay
55ff45a5c2
Support negative numbers in Literal::from_str 2021-07-18 14:08:34 -07:00
Aaron Hill
7ca089c6d2
Only use assign_id! for ast nodes that support attributes 2021-07-17 23:03:58 -05:00
Aaron Hill
d6e3c11101
Add additional missing lint handling logic 2021-07-17 23:03:58 -05:00
Aaron Hill
ddd544856e
Compute a better lint_node_id during expansion
When we need to emit a lint at a macro invocation, we currently use the
`NodeId` of its parent definition (e.g. the enclosing function). This
means that any `#[allow]` / `#[deny]` attributes placed 'closer' to the
macro (e.g. on an enclosing block or statement) will have no effect.

This commit computes a better `lint_node_id` in `InvocationCollector`.
When we visit/flat_map an AST node, we assign it a `NodeId` (earlier
than we normally would), and store than `NodeId` in current
`ExpansionData`. When we collect a macro invocation, the current
`lint_node_id` gets cloned along with our `ExpansionData`, allowing it
to be used if we need to emit a lint later on.

This improves the handling of `#[allow]` / `#[deny]` for
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` and some `asm!`-related lints.
The 'legacy derive helpers' lint retains its current behavior
(I've inlined the now-removed `lint_node_id` function), since
there isn't an `ExpansionData` readily available.
2021-07-17 23:03:56 -05:00
Camille GILLOT
078dd37f88 Use LocalExpnId where possible. 2021-07-17 19:41:02 +02:00
Guillaume Gomez
4d141f5e4c
Rollup merge of - petrochenkov:builderhelp, r=oli-obk
expand: Support helper attributes for built-in derive macros

This is needed for https://github.com/rust-lang/rust/pull/86735 (derive macro `Default` should have a helper attribute `default`).

With this PR we can specify helper attributes for built-in derives using syntax `#[rustc_builtin_macro(MacroName, attributes(attr1, attr2, ...))]` which mirrors equivalent syntax for proc macros `#[proc_macro_derive(MacroName, attributes(attr1, attr2, ...))]`.
Otherwise expansion infra was already ready for this.
The attribute parsing code is shared between proc macro derives and built-in macros (`fn parse_macro_name_and_helper_attrs`).
2021-07-14 19:53:35 +02:00
bors
ee5ed4a88d Auto merge of - JohnTitor:rollup-8ltidsq, r=JohnTitor
Rollup of 6 pull requests

Successful merges:

 -  (Search result colors)
 -  (Make BTreeSet::split_off name elements like other set methods do)
 -  (Unignore some pretty printing tests)
 -  (Upgrade `cc` crate to 1.0.69)
 -  (Suggest a path separator if a stray colon is found in a match arm)
 -  (Add GUI test for "go to first" feature)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-07-14 12:49:45 +00:00
Fabian Wolff
2362450425 Suggest a path separator if a stray colon is found in a match arm
Co-authored-by: Esteban Kuber <estebank@users.noreply.github.com>
2021-07-14 01:15:59 +02:00
Camille GILLOT
616ce3c5c0 Cache expansion hash. 2021-07-13 23:10:56 +02:00
Vadim Petrochenkov
6c9ea1e8a9 expand: Support helper attributes for built-in derive macros 2021-07-13 21:59:22 +03:00
Vadim Petrochenkov
ece6f68186 rustc_expand: Simplify span quoting in proc macro server
- The `Rustc::expn_id` field kept redundant information
- `SyntaxContext` is no longer thrown away before `save_proc_macro_span` because it's thrown away during metadata encoding anyway
2021-07-11 00:39:37 +03:00
Vadim Petrochenkov
de897f5205 rustc_expand: Remove redundant field from proc macro expander structures
This information is already available from `ExpnData`
2021-07-10 23:22:27 +03:00
Vadim Petrochenkov
28f4dba438 rustc_span: Revert addition of proc_macro field to ExpnKind::Macro
The flag has a vague meaning and is used for a single diagnostic change that is low benefit and appears only under `-Z macro_backtrace`.
2021-07-10 23:03:35 +03:00
Guillaume Gomez
a2654fb64c Rework SESSION_GLOBALS API to prevent overwriting it 2021-07-08 16:16:28 +02:00
Ryan Levick
1d49658f5c Change or_patterns_back_compat lint to rust_2021_incompatible_or_patterns 2021-07-06 20:11:45 +02:00
Camille GILLOT
3162c37b59 Store macro parent module in ExpnData. 2021-07-06 08:07:06 +02:00
Bernhard Schuster
67e6a81315 add track_path::path fn for proc-macro usage
Ref 
2021-07-02 07:13:19 +02:00
Mara Bos
06db210459 Don't lint :pat when re-parsing a macro from another crate. 2021-06-24 22:04:55 +00:00
Yuki Okushi
8b9e138ecd
Rollup merge of - petrochenkov:derefact, r=Aaron1011
expand: Move some more derive logic to rustc_builtin_macros

And cleanup some `unwrap`s in `cfg_eval`.

Refactorings extracted from https://github.com/rust-lang/rust/pull/83354 and https://github.com/rust-lang/rust/pull/86057.
r? ``@Aaron1011``
2021-06-21 09:42:19 +09:00
Deadbeef
37d0d2705d
Do not set depth to 0 in fully_expand_fragment 2021-06-21 02:05:37 +08:00
Vadim Petrochenkov
3f0729f378 expand: Move some more derive logic to rustc_builtin_macros 2021-06-20 18:48:42 +03:00
Yuki Okushi
4f8e0ebcc5
Use AttrVec for Arm, FieldDef, and Variant 2021-06-17 08:04:54 +09:00
LeSeulArtichaut
e3ca81fd5a Use the now available implementation of IntoIterator for arrays 2021-06-14 23:40:09 +02:00
Ryan Levick
6936349233 Add support for using qualified paths with structs in expression and pattern
position.
2021-06-10 13:18:41 +02:00
Mara Bos
d5aec64c12 Add proc_macro::Span::{before, after}. 2021-06-09 12:43:59 +00:00
Aaron Hill
822f800ad7
Include macro name in 'local ambiguity' error
Currently, we only point at the span of the macro argument. When the
macro call is itself generated by another macro, this can make it
difficult or impossible to determine which macro is responsible for
producing the error.
2021-06-07 20:17:48 -05:00
Joshua Nelson
15fec1fb80 Remove doc(include) 2021-06-04 08:05:54 -04:00
Yuki Okushi
36f1ed6de2
Rollup merge of - bjorn3:less_feature_gates, r=jyn514
Remove unused feature gates

The first commit removes a usage of a feature gate, but I don't expect it to be controversial as the feature gate was only used to workaround a limitation of rust in the past. (closures never being `Clone`)

The second commit uses `#[allow_internal_unstable]` to avoid leaking the `trusted_step` feature gate usage from inside the index newtype macro. It didn't work for the `min_specialization` feature gate though.

The third commit removes (almost) all feature gates from the compiler that weren't used anyway.
2021-06-04 13:42:54 +09:00
bjorn3
312f964478 Remove unused feature gates 2021-05-31 13:55:43 +02:00
Aaron Hill
d874ecc84f
Use correct edition when parsing :pat matchers
As described in issue , we currently do not properly decode
`SyntaxContext::root()` and `ExpnId::root()` from foreign crates. As a
result, when we decode a span from a foreign crate with
`SyntaxContext::root()`, we end up up considering it to have the edition
of the *current* crate, instead of the foreign crate where it was
originally created.

A full fix for this issue will be a fairly significant undertaking.
Fortunately, it's possible to implement a partial fix, which gives us
the correct edition-dependent behavior for `:pat` matchers when the
macro is loaded from another crate. Since we have the edition of the
macro's defining crate available, we can 'recover' from seeing a
`SyntaxContext::root()` and use the edition of the macro's defining
crate.

Any solution to issue  must reproduce the behavior of this
targeted fix - properly preserving a foreign `SyntaxContext::root()`
means (among other things) preserving its edition, which by definition
is the edition of the foreign crate itself. Therefore, this fix moves us
closer to the correct overall solution, and does not expose any new
incorrect behavior to macros.
2021-05-29 13:09:14 -05:00
Pietro Albini
9e22b844dd remove cfg(bootstrap) 2021-05-24 11:07:48 -04:00
David Tolnay
34585cb678
impl FromStr for proc_macro::Literal 2021-05-19 11:38:24 -07:00
bors
e1ff91f439 Auto merge of - cbeuw:remap-std, r=michaelwoerister
Fix `--remap-path-prefix` not correctly remapping `rust-src` component paths and unify handling of path mapping with virtualized paths

This PR fixes  ("Binaries end up containing path to the rust-src component despite `--remap-path-prefix`") by preventing real local filesystem paths from reaching compilation output if the path is supposed to be remapped.

`RealFileName::Named` introduced in  is now renamed as `LocalPath`, because this variant wraps a (most likely) valid local filesystem path.

`RealFileName::Devirtualized` is renamed as `Remapped` to be used for remapped path from a real path via `--remap-path-prefix` argument, as well as real path inferred from a virtualized (during compiler bootstrapping) `/rustc/...` path. The `local_path` field is now an `Option<PathBuf>`, as it will be set to `None` before serialisation, so it never reaches any build output. Attempting to serialise a non-`None` `local_path` will cause an assertion faliure.

When a path is remapped, a `RealFileName::Remapped` variant is created. The original path is preserved in `local_path` field and the remapped path is saved in `virtual_name` field. Previously, the `local_path` is directly modified which goes against its purpose of "suitable for reading from the file system on the local host".

`rustc_span::SourceFile`'s fields `unmapped_path` (introduced by ) and `name_was_remapped` (introduced by  when `--remap-path-prefix` feature originally added) are removed, as these two pieces of information can be inferred from the `name` field: if it's anything other than a `FileName::Real(_)`, or if it is a `FileName::Real(RealFileName::LocalPath(_))`, then clearly `name_was_remapped` would've been false and `unmapped_path` would've been `None`. If it is a `FileName::Real(RealFileName::Remapped{local_path, virtual_name})`, then `name_was_remapped` would've been true and `unmapped_path` would've been `Some(local_path)`.

cc `@eddyb` who implemented `/rustc/...` path devirtualisation
2021-05-12 11:05:56 +00:00
Aaron Hill
f916b0474a
Implement span quoting for proc-macros
This PR implements span quoting, allowing proc-macros to produce spans
pointing *into their own crate*. This is used by the unstable
`proc_macro::quote!` macro, allowing us to get error messages like this:

```
error[E0412]: cannot find type `MissingType` in this scope
  --> $DIR/auxiliary/span-from-proc-macro.rs:37:20
   |
LL | pub fn error_from_attribute(_args: TokenStream, _input: TokenStream) -> TokenStream {
   | ----------------------------------------------------------------------------------- in this expansion of procedural macro `#[error_from_attribute]`
...
LL |             field: MissingType
   |                    ^^^^^^^^^^^ not found in this scope
   |
  ::: $DIR/span-from-proc-macro.rs:8:1
   |
LL | #[error_from_attribute]
   | ----------------------- in this macro invocation
```

Here, `MissingType` occurs inside the implementation of the proc-macro
`#[error_from_attribute]`. Previosuly, this would always result in a
span pointing at `#[error_from_attribute]`

This will make many proc-macro-related error message much more useful -
when a proc-macro generates code containing an error, users will get an
error message pointing directly at that code (within the macro
definition), instead of always getting a span pointing at the macro
invocation site.

This is implemented as follows:
* When a proc-macro crate is being *compiled*, it causes the `quote!`
  macro to get run. This saves all of the sapns in the input to `quote!`
  into the metadata of *the proc-macro-crate* (which we are currently
  compiling). The `quote!` macro then expands to a call to
  `proc_macro::Span::recover_proc_macro_span(id)`, where `id` is an
opaque identifier for the span in the crate metadata.
* When the same proc-macro crate is *run* (e.g. it is loaded from disk
  and invoked by some consumer crate), the call to
`proc_macro::Span::recover_proc_macro_span` causes us to load the span
from the proc-macro crate's metadata. The proc-macro then produces a
`TokenStream` containing a `Span` pointing into the proc-macro crate
itself.

The recursive nature of 'quote!' can be difficult to understand at
first. The file `src/test/ui/proc-macro/quote-debug.stdout` shows
the output of the `quote!` macro, which should make this eaier to
understand.

This PR also supports custom quoting spans in custom quote macros (e.g.
the `quote` crate). All span quoting goes through the
`proc_macro::quote_span` method, which can be called by a custom quote
macro to perform span quoting. An example of this usage is provided in
`src/test/ui/proc-macro/auxiliary/custom-quote.rs`

Custom quoting currently has a few limitations:

In order to quote a span, we need to generate a call to
`proc_macro::Span::recover_proc_macro_span`. However, proc-macros
support renaming the `proc_macro` crate, so we can't simply hardcode
this path. Previously, the `quote_span` method used the path
`crate::Span` - however, this only works when it is called by the
builtin `quote!` macro in the same crate. To support being called from
arbitrary crates, we need access to the name of the `proc_macro` crate
to generate a path. This PR adds an additional argument to `quote_span`
to specify the name of the `proc_macro` crate. Howver, this feels kind
of hacky, and we may want to change this before stabilizing anything
quote-related.

Additionally, using `quote_span` currently requires enabling the
`proc_macro_internals` feature. The builtin `quote!` macro
has an `#[allow_internal_unstable]` attribute, but this won't work for
custom quote implementations. This will likely require some additional
tricks to apply `allow_internal_unstable` to the span of
`proc_macro::Span::recover_proc_macro_span`.
2021-05-12 00:51:31 -04:00
Dylan DPC
0c8c21d224
Rollup merge of - jyn514:doc-cfg, r=petrochenkov
Unify rustc and rustdoc parsing of `cfg()`

This extracts a new `parse_cfg` function that's used between both.

- Treat `#[doc(cfg(x), cfg(y))]` the same as `#[doc(cfg(x)]
  #[doc(cfg(y))]`. Previously it would be completely ignored.
- Treat `#[doc(inline, cfg(x))]` the same as `#[doc(inline)]
  #[doc(cfg(x))]`. Previously, the cfg would be ignored.
- Pass the cfg predicate through to rustc_expand to be validated

Technically this is a breaking change, but doc_cfg is still nightly so I don't think it matters.

Fixes https://github.com/rust-lang/rust/issues/84437.

r? `````````@petrochenkov`````````
2021-05-07 16:19:19 +02:00
Deadbeef
4617b03316
E0583: Include secondary path in error message 2021-05-06 09:40:05 +08:00
Andy Wang
5417b45c26
Use local and remapped paths where appropriate 2021-05-05 15:31:28 +01:00
Andy Wang
9e0426d784
Make local_path in RealFileName::Remapped Option to be removed in exported metadata 2021-05-05 15:10:57 +01:00
Andy Wang
6720a37042
Rename RealFileName::Named to LocalPath and Devirtualized to Remapped 2021-05-05 15:10:50 +01:00
Joshua Nelson
6eb4735acc Unify rustc and rustdoc parsing of cfg()
This extracts a new `parse_cfg` function that's used between both.

- Treat `#[doc(cfg(x), cfg(y))]` the same as `#[doc(cfg(x)]
  #[doc(cfg(y))]`. Previously it would be completely ignored.
- Treat `#[doc(inline, cfg(x))]` the same as `#[doc(inline)]
  #[doc(cfg(x))]`. Previously, the cfg would be ignored.
- Pass the cfg predicate through to rustc_expand to be validated

Co-authored-by: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
2021-05-03 12:49:43 -04:00
hi-rustin
461f52071d use full path for E0761 2021-05-03 18:57:48 +08:00
hi-rustin
f758eb664e use double quotes for E0761 2021-05-03 16:02:54 +08:00
bors
bcd696d722 Auto merge of - crlf0710:impl_main_by_path, r=petrochenkov
Implement RFC 1260 with feature_name `imported_main`.

This is the second extraction part of  plus additional adjustments.
This (mostly) implements RFC 1260.

However there's still one test case failure in the extern crate case. Maybe `LocalDefId` doesn't work here? I'm not sure.

cc https://github.com/rust-lang/rust/issues/28937
r? `@petrochenkov`
2021-04-30 06:59:37 +00:00
Charles Lew
d261df4a72 Implement RFC 1260 with feature_name imported_main. 2021-04-29 08:35:08 +08:00
bors
ca075d268d Auto merge of - mark-i-m:stabilize-pat2015, r=nikomatsakis
Stabilize `:pat_param` and remove `:pat2021`

Blocked on 

cc `@rust-lang/lang` 

If I understand `@nikomatsakis` in  https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/or.20patterns/near/231133873, another FCP is not needed.

r? `@nikomatsakis`
2021-04-28 20:35:17 +00:00
mark
2a9db919ff remove pat2021 2021-04-27 21:15:59 -05:00
klensy
f43ee8ebf6 fix few typos 2021-04-19 15:57:08 +03:00
mark
0566ccc72f rename pat2015 to pat_param 2021-04-15 13:52:09 -05:00
mark
ebc4acee91 stabilize :pat2015, leave :pat2021 gated 2021-04-15 13:52:09 -05:00
Aaron Hill
a93c4f05de
Implement token-based handling of attributes during expansion
This PR modifies the macro expansion infrastructure to handle attributes
in a fully token-based manner. As a result:

* Derives macros no longer lose spans when their input is modified
  by eager cfg-expansion. This is accomplished by performing eager
  cfg-expansion on the token stream that we pass to the derive
  proc-macro
* Inner attributes now preserve spans in all cases, including when we
  have multiple inner attributes in a row.

This is accomplished through the following changes:

* New structs `AttrAnnotatedTokenStream` and `AttrAnnotatedTokenTree` are introduced.
  These are very similar to a normal `TokenTree`, but they also track
  the position of attributes and attribute targets within the stream.
  They are built when we collect tokens during parsing.
  An `AttrAnnotatedTokenStream` is converted to a regular `TokenStream` when
  we invoke a macro.
* Token capturing and `LazyTokenStream` are modified to work with
  `AttrAnnotatedTokenStream`. A new `ReplaceRange` type is introduced, which
  is created during the parsing of a nested AST node to make the 'outer'
  AST node aware of the attributes and attribute target stored deeper in the token stream.
* When we need to perform eager cfg-expansion (either due to `#[derive]` or `#[cfg_eval]`),
we tokenize and reparse our target, capturing additional information about the locations of
`#[cfg]` and `#[cfg_attr]` attributes at any depth within the target.
This is a performance optimization, allowing us to perform less work
in the typical case where captured tokens never have eager cfg-expansion run.
2021-04-11 01:31:36 -04:00
Aaron Hill
21e6cc19fe
Expand derive invocations in left-to-right order
While derives were being collected in left-to-order order, the
corresponding `Invocation`s were being pushed in the wrong order.
2021-04-10 17:29:20 -04:00
Dylan DPC
4d5bb1ca22
Rollup merge of - JohnTitor:unused-doc-comments-on-macros, r=varkor
Trigger `unused_doc_comments` on macros at once

Fixes 
2021-04-07 13:07:12 +02:00
Yuki Okushi
67ffbedada
Rollup merge of - petrochenkov:emptyexpr, r=davidtwco
expand: Do not ICE when a legacy AST-based macro attribute produces and empty expression

Fixes https://github.com/rust-lang/rust/issues/80251

The reported error is the same as for `let _ = #[cfg(FALSE)] EXPR;`
2021-04-06 06:24:12 +09:00
Vadim Petrochenkov
fbf1bec482 resolve/expand: Cache intermediate results of #[derive] expansion 2021-04-04 17:51:41 +03:00
Yuki Okushi
81f00c98a6 Trigger unused_doc_comments on macros at once 2021-04-04 05:06:51 +09:00
Vadim Petrochenkov
cd22425990 expand: Do not ICE when a legacy AST-based macro attribute produces and empty expression 2021-04-03 19:42:09 +03:00
hi-rustin
aa987c2f57 address comments 2021-04-02 08:08:02 +08:00
hi-rustin
2c66e15468 add OR_PATTERNS_BACK_COMPAT lint
test: add more cases

test: add comments

refine msg
2021-04-01 23:14:14 +08:00
Joshua Nelson
441dc3640a Remove (lots of) dead code
Found with https://github.com/est31/warnalyzer.

Dubious changes:
- Is anyone else using rustc_apfloat? I feel weird completely deleting
  x87 support.
- Maybe some of the dead code in rustc_data_structures, in case someone
  wants to use it in the future?
- Don't change rustc_serialize

  I plan to scrap most of the json module in the near future (see
  https://github.com/rust-lang/compiler-team/issues/418) and fixing the
  tests needed more work than I expected.

TODO: check if any of the comments on the deleted code should be kept.
2021-03-27 22:16:33 -04:00
Dylan DPC
b2e254318d
Rollup merge of - cuviper:iter-zip, r=m-ou-se
Add function core::iter::zip

This makes it a little easier to `zip` iterators:

```rust
for (x, y) in zip(xs, ys) {}
// vs.
for (x, y) in xs.into_iter().zip(ys) {}
```

You can `zip(&mut xs, &ys)` for the conventional `iter_mut()` and
`iter()`, respectively. This can also support arbitrary nesting, where
it's easier to see the item layout than with arbitrary `zip` chains:

```rust
for ((x, y), z) in zip(zip(xs, ys), zs) {}
for (x, (y, z)) in zip(xs, zip(ys, zs)) {}
// vs.
for ((x, y), z) in xs.into_iter().zip(ys).zip(xz) {}
for (x, (y, z)) in xs.into_iter().zip((ys.into_iter().zip(xz)) {}
```

It may also format more nicely, especially when the first iterator is a
longer chain of methods -- for example:

```rust
    iter::zip(
        trait_ref.substs.types().skip(1),
        impl_trait_ref.substs.types().skip(1),
    )
    // vs.
    trait_ref
        .substs
        .types()
        .skip(1)
        .zip(impl_trait_ref.substs.types().skip(1))
```

This replaces the tuple-pair `IntoIterator` in .
There is prior art for the utility of this in [`itertools::zip`].

[`itertools::zip`]: https://docs.rs/itertools/0.10.0/itertools/fn.zip.html
2021-03-27 20:37:07 +01:00
Josh Stone
72ebebe474 Use iter::zip in compiler/ 2021-03-26 09:32:31 -07:00
Aaron Hill
fe60f19f7e
Ban custom inner attributes in expressions and statements 2021-03-25 18:05:30 -04:00
Yuki Okushi
50d048f142
Rollup merge of - mark-i-m:rename-pat2018, r=joshtriplett
rename :pat2018 -> :pat2015

as requested by T-lang on zulip: https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/or.20patterns/near/231133873

No functional changes here... just renaming.

r? `@nikomatsakis`
2021-03-23 10:15:43 +09:00
bors
5d04957a4b Auto merge of - mark-i-m:stabilize-or-pattern, r=nikomatsakis
Stabilize or_patterns (RFC 2535, 2530, 2175)

closes 

This PR stabilizes the or_patterns feature in Rust 1.53.

This is blocked on the following (in order):
- [x] The crater run in https://github.com/rust-lang/rust/pull/78935#issuecomment-731564021
- [x] The resolution of the unresolved questions and a second crater run (https://github.com/rust-lang/rust/pull/78935#issuecomment-735412705)
    - It looks like we will need to pursue some sort of edition-based transition for `:pat`.
- [x] Nomination and discussion by T-lang
- [x] Implement new behavior for `:pat` based on consensus (https://github.com/rust-lang/rust/pull/80100).
- [ ] An FCP on stabilization

EDIT: Stabilization report is in https://github.com/rust-lang/rust/pull/79278#issuecomment-772815177
2021-03-22 19:48:27 +00:00
mark
8c4b3dbb50 rename :pat2018 -> :pat215 2021-03-22 12:40:23 -05:00
mark
db5629adcb stabilize or_patterns 2021-03-19 19:45:32 -05:00
Aaron Hill
f6a35d7df2
Extend proc_macro_back_compat lint to js-sys
With this PR, we now lint for all cases where we perform some kind of
proc-macro back-compat hack.

The `js-sys` had an internal fix made to properly handle
`None`-delimited groups, so we need to manually check the version in the
filename. As a result, we no longer apply the back-compat hack to cases
where the version number is missing file the file path. This should not
affect any users of the `crates.io` crate.
2021-03-19 14:40:20 -04:00
Aaron Hill
390d1ef6d0
Extend proc_macro_back_compat lint to actix-web
Unlike the other cases of this lint, there's no simple way to detect if
an old version of the relevant crate (`syn`) is in use. The `actix-web`
crate only depends on `pin-project` v1.0.0, so checking the version of
`actix-web` does not guarantee that a new enough version of
`pin-project` (and therefore `syn`) is in use.

Instead, we rely on the fact that virtually all of the regressed crates
are pinned to a pre-1.0 version of `pin-project`. When this is the case,
bumping the `actix-web` dependency will pull in the *latest* version of
`pin-project`, which has an explicit dependency on a newer v dependency
on a newer version of `syn`.

The lint message tells users to update `actix-web`, since that's what
they're most likely to have control over. We could potentially tell them
to run `cargo update -p syn`, but I think it's more straightforward to
suggest an explicit change to the `Cargo.toml`

The `actori-web` fork had its last commit over a year ago, and appears
to just be a renamed fork of `actix-web`. Therefore, I've removed the
`actori-web` check entirely - any crates that actually get broken can
simply update `syn` themselves.
2021-03-18 12:09:14 -04:00
Dylan DPC
7cd7dee315
Rollup merge of - Aaron1011:lint-procedural-masquerade, r=petrochenkov
Extend `proc_macro_back_compat` lint to `procedural-masquerade`

We now lint on *any* use of `procedural-masquerade` crate. While this
crate still exists, its main reverse dependency (`cssparser`) no longer
depends on it. Any crates still depending off should stop doing so, as
it only exists to support very old Rust versions.

If a crate actually needs to support old versions of rustc via
`procedural-masquerade`, then they'll just need to accept the warning
until we remove it entirely (at the same time as the back-compat hack).
The latest version of `procedural-masquerade` does work with the
latest rustc, but trying to check for the version seems like more
trouble than it's worth.

While working on this, I realized that the `proc-macro-hack` check was
never actually doing anything. The corresponding enum variant in
`proc-macro-hack` is named `Value` or `Nested` - it has never been
called `Input`. Due to a strange Crater issue, the Crater run that
tested adding this did *not* end up testing it - some of the crates that
would have failed did not actually have their tests checked, making it
seem as though the `proc-macro-hack` check was working.

The Crater issue is being discussed at
https://rust-lang.zulipchat.com/#narrow/stream/242791-t-infra/topic/Nearly.20identical.20Crater.20runs.20processed.20a.20crate.20differently/near/230406661

Despite the `proc-macro-hack` check not actually doing anything, we
haven't gotten any reports from users about their build being broken.
I went ahead and removed it entirely, since it's clear that no one is
being affected by the `proc-macro-hack` regression in practice.
2021-03-18 00:28:10 +01:00
Vadim Petrochenkov
d1522b39dd ast: Reduce size of ExprKind by boxing fields of ExprKind::Struct 2021-03-16 11:41:24 +03:00
Vadim Petrochenkov
b25d3ba781 ast/hir: Rename field-related structures
StructField -> FieldDef ("field definition")
Field -> ExprField ("expression field", not "field expression")
FieldPat -> PatField ("pattern field", not "field pattern")

Also rename visiting and other methods working on them.
2021-03-16 11:41:24 +03:00
Aaron Hill
d6a7c1d47f
Extend proc_macro_back_compat lint to procedural-masquerade
We now lint on *any* use of `procedural-masquerade` crate. While this
crate still exists, its main reverse dependency (`cssparser`) no longer
depends on it. Any crates still depending off should stop doing so, as
it only exists to support very old Rust versions.

If a crate actually needs to support old versions of rustc via
`procedural-masquerade`, then they'll just need to accept the warning
until we remove it entirely (at the same time as the back-compat hack).
The latest version of `procedural-masquerade` does not work with the
latest rustc, but trying to check for the version seems like more
trouble than it's worth.

While working on this, I realized that the `proc-macro-hack` check was
never actually doing anything. The corresponding enum variant in
`proc-macro-hack` is named `Value` or `Nested` - it has never been
called `Input`. Due to a strange Crater issue, the Crater run that
tested adding this did *not* end up testing it - some of the crates that
would have failed did not actually have their tests checked, making it
seem as though the `proc-macro-hack` check was working.

The Crater issue is being discussed at
https://rust-lang.zulipchat.com/#narrow/stream/242791-t-infra/topic/Nearly.20identical.20Crater.20runs.20processed.20a.20crate.20differently/near/230406661

Despite the `proc-macro-hack` check not actually doing anything, we
haven't gotten any reports from users about their build being broken.
I went ahead and removed it entirely, since it's clear that no one is
being affected by the `proc-macro-hack` regression in practice.
2021-03-15 16:00:49 -04:00