Detect missing `if let` or `let-else`
During `let` binding parse error and encountering a block, detect if there is a likely missing `if` or `else`:
```
error: expected one of `.`, `;`, `?`, `else`, or an operator, found `{`
--> $DIR/missing-if-let-or-let-else.rs:14:25
|
LL | let Some(x) = foo() {
| ^ expected one of `.`, `;`, `?`, `else`, or an operator
|
help: you might have meant to use `if let`
|
LL | if let Some(x) = foo() {
| ++
help: alternatively, you might have meant to use `let else`
|
LL | let Some(x) = foo() else {
| ++++
```
Fixrust-lang/rust#107806.
During `let` binding parse error and encountering a block, detect if there is a likely missing `if` or `else`:
```
error: expected one of `.`, `;`, `?`, `else`, or an operator, found `{`
--> $DIR/missing-if-let-or-let-else.rs:14:25
|
LL | let Some(x) = foo() {
| ^ expected one of `.`, `;`, `?`, `else`, or an operator
|
help: you might have meant to use `if let`
|
LL | if let Some(x) = foo() {
| ++
help: alternatively, you might have meant to use `let else`
|
LL | let Some(x) = foo() else {
| ++++
```
This commit does the following.
- Changes it from `Lrc<Box<dyn ToAttrTokenStream>>` to
`Lrc<LazyAttrTokenStreamInner>`.
- Reworks `LazyAttrTokenStreamImpl` as `LazyAttrTokenStreamInner`, which
is a two-variant enum.
- Removes the `ToAttrTokenStream` trait and the two impls of it.
The recursion limit must be increased in some crates otherwise rustdoc
aborts.
Specifically: `TokenCursor`, `TokenTreeCursor`,
`LazyAttrTokenStreamImpl`, `FlatToken`, `make_attr_token_stream`,
`ParserRange`, `NodeRange`. `ParserReplacement`, and `NodeReplacement`.
These are all related to token streams, rather than actual parsing.
This will facilitate the simplifications in the next commit.
Make #![feature(let_chains)] bootstrap conditional in compiler/
Let chains have been stabilized recently in #132833, so we can remove the gating from our uses in the compiler (as the compiler uses edition 2024).
Revert <https://github.com/rust-lang/rust/pull/138084> to buy time to
consider options that avoids breaking downstream usages of cargo on
distributed `rustc-src` artifacts, where such cargo invocations fail due
to inability to inherit `lints` from workspace root manifest's
`workspace.lints` (this is only valid for the source rust-lang/rust
workspace, but not really the distributed `rustc-src` artifacts).
This breakage was reported in
<https://github.com/rust-lang/rust/issues/138304>.
This reverts commit 48caf81484, reversing
changes made to c6662879b2.
```
error: couldn't read `$DIR/not-utf8-bin-file.rs`: stream did not contain valid UTF-8
--> $DIR/not-utf8-2.rs:6:5
|
LL | include!("not-utf8-bin-file.rs");
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
note: `[193]` is not valid utf-8
--> $DIR/not-utf8-bin-file.rs:2:14
|
LL | let _ = "�|�␂!5�cc␕␂��";
| ^
= note: this error originates in the macro `include` (in Nightly builds, run with -Z macro-backtrace for more info)
```
When we attempt to load a Rust source code file, if there is a OS file failure we try reading the file as bytes. If that succeeds we try to turn it into UTF-8. If *that* fails, we provide additional context about *where* the file has the first invalid UTF-8 character.
Fix#76869.
We already do this for a number of crates, e.g. `rustc_middle`,
`rustc_span`, `rustc_metadata`, `rustc_span`, `rustc_errors`.
For the ones we don't, in many cases the attributes are a mess.
- There is no consistency about order of attribute kinds (e.g.
`allow`/`deny`/`feature`).
- Within attribute kind groups (e.g. the `feature` attributes),
sometimes the order is alphabetical, and sometimes there is no
particular order.
- Sometimes the attributes of a particular kind aren't even grouped
all together, e.g. there might be a `feature`, then an `allow`, then
another `feature`.
This commit extends the existing sorting to all compiler crates,
increasing consistency. If any new attribute line is added there is now
only one place it can go -- no need for arbitrary decisions.
Exceptions:
- `rustc_log`, `rustc_next_trait_solver` and `rustc_type_ir_macros`,
because they have no crate attributes.
- `rustc_codegen_gcc`, because it's quasi-external to rustc (e.g. it's
ignored in `rustfmt.toml`).
Currently we have an awkward mix of fallible and infallible functions:
```
new_parser_from_source_str
maybe_new_parser_from_source_str
new_parser_from_file
(maybe_new_parser_from_file) // missing
(new_parser_from_source_file) // missing
maybe_new_parser_from_source_file
source_str_to_stream
maybe_source_file_to_stream
```
We could add the two missing functions, but instead this commit removes
of all the infallible ones and renames the fallible ones leaving us with
these which are all fallible:
```
new_parser_from_source_str
new_parser_from_file
new_parser_from_source_file
source_str_to_stream
source_file_to_stream
```
This requires making `unwrap_or_emit_fatal` public so callers of
formerly infallible functions can still work.
This does make some of the call sites slightly more verbose, but I think
it's worth it for the simpler API. Also, there are two `catch_unwind`
calls and one `catch_fatal_errors` call in this diff that become
removable thanks this change. (I will do that in a follow-up PR.)
The first one is out-of-date -- there are no longer functions expr,
item, stmt. And I don't know what a "HOF" is.
The second one doesn't really tell you anything.
- Convert it from a macro to a function, which is nicer.
- Rename it as `unwrap_or_emit_fatal`, which is clearer.
- Fix the comment. In particular, `panictry!` no longer exists.
- Remove the unnecessary `use` declaration.
It has a single call site.
This also means `CFG_ATTR_{GRAMMAR_HELP,NOTE_REF}` can be moved into
`parse_cfg_attr`, now that it's the only function that uses them.
And the commit removes the line break in the URL.
Lexing converts source text into a token stream. Parsing converts a
token stream into AST fragments. This commit renames several lexing
operations that have "parse" in the name. I think these names have been
subtly confusing me for years.
This is just a `s/parse/lex/` on function names, with one exception:
`parse_stream_from_source_str` becomes `source_str_to_stream`, to make
it consistent with the existing `source_file_to_stream`. The commit also
moves that function's location in the file to be just above
`source_file_to_stream`.
The commit also cleans up a few comments along the way.
I tried debugging a parser-related issue but found it annoying to not be
able to easily peek into the Parser's token stream.
Add a convenience fn that offers an opinionated view into the parser,
but one that is useful for answering basic questions about parser state.
Existing names for values of this type are `sess`, `parse_sess`,
`parse_session`, and `ps`. `sess` is particularly annoying because
that's also used for `Session` values, which are often co-located, and
it can be difficult to know which type a value named `sess` refers to.
(That annoyance is the main motivation for this change.) `psess` is nice
and short, which is good for a name used this much.
The commit also renames some `parse_sess_created` values as
`psess_created`.
