syntax_ext: format: fix ICE with bad named arguments
Fixes#35082 by guarding against a new case of malformed invocation not previously covered.
r? @alexcrichton
This commit removed the restriction of only allowing one type per argument.
This is achieved by adding mappings between macro arguments and format
placeholders, then taking the mapping into consideration when emitting
the Arguments expression.
syntax_ext: format: fix implicit positional arguments
syntax_ext: format: don't panic if no args given for implicit positional args
Check the list lengths before use.
Fixes regression of `compile-fail/macro-backtrace-println.rs`.
syntax_ext: format: also map CountIsParam indices to expanded args
syntax_ext: format: fix ICE in case of malformed format args
Converts named argument references into indices, right after
verification as suggested by @alexcrichton. This drastically simplifies
the whole process!
format: beautifully get rid of ArgumentNext and CountIsNextParam
Now that CountIsNextParam and ArgumentNext are resolved during parse,
the need for handling them outside of libfmt_macros is obviated.
Note: *one* instance of implicit reference handling still remains, and
that's for implementing `all_args_simple`. It's trivial enough though,
so in this case it may be tolerable.
Fixes the formatting for inline assembly clobbers used in the book.
As this causes llvm to silently ignore the clobber an error is also
added to catch cases in which the wrong formatting was used.
Additionally a test case is added to confirm that this error works.
This is a spiritual succesor to #34268/8531d581, in which we replaced a
number of matches of None to the unit value with `if let` conditionals
where it was judged that this made for clearer/simpler code (as would be
recommended by Manishearth/rust-clippy's `single_match` lint). The same
rationale applies to matches of None to the empty block.
To allow these braced macro invocation, this PR removes the optional expression from `ast::Block` and instead uses a `StmtKind::Expr` at the end of the statement list.
Currently, braced macro invocations in blocks can expand into statements (and items) except when they are last in a block, in which case they can only expand into expressions.
For example,
```rust
macro_rules! make_stmt {
() => { let x = 0; }
}
fn f() {
make_stmt! {} //< This is OK...
let x = 0; //< ... unless this line is commented out.
}
```
Fixes#34418.
syntax-[breaking-change] cc #31645
(Only breaking because ast::TokenTree is now tokenstream::TokenTree.)
This pull request refactors TokenTrees into their own file as src/libsyntax/tokenstream.rs, moving them out of src/libsyntax/ast.rs, in order to prepare for an accompanying TokenStream implementation (per RFC 1566).
Allow `concat_idents!` in type positions as well as in expression positions
This allows the `concat_idents!` macro in type positions as well as in expression positions.
r? @nrc
syntax_ext: format: nest_level's are no more
Just noticed this while working on #33642 and here's a quick fix, shouldn't touch anything else. It's some historic code indeed...
Jeffrey Seyfried