* In noop_fold_expr, call new_span in these cases:
- ExprMethodCall's identifier
- ExprField's identifier
- ExprTupField's integer
Calling new_span for ExprMethodCall's identifier is necessary to print
an acceptable diagnostic for write!(&2, ""). We see this error:
<std macros>:2:20: 2:66 error: type `&mut _` does not implement any method in scope named `write_fmt`
<std macros>:2 ( & mut * $ dst ) . write_fmt ( format_args ! ( $ ( $ arg ) * ) ) )
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
With this change, we also see a macro expansion backtrace leading to
the write!(&2, "") call site.
* After fully expanding a macro, we replace the expansion expression's
span with the original span. Call fld.new_span to add a backtrace to
this span. (Note that I'm call new_span after bt.pop(), so the macro
just expanded isn't on the backtrace.)
The motivating example for this change is println!("{}"). The format
string literal is concat!($fmt, "arg") and is inside the libstd macro.
We need to see the backtrace to find the println! call site.
* Add a backtrace to the format_args! format expression span.
Addresses #23459
Example showing sample inputs, old message, new message:
https://gist.github.com/nikomatsakis/11126784ac678b7eb6ba
Also adds infrastructure for reporting suggestions \"in situ\" and does some (minor) cleanups to `CodeMap`.
r? @brson
Statement macros are now treated somewhat like item macros, in that a statement macro can now expand into a series of statements, rather than just a single statement.
This allows statement macros to be nested inside other kinds of macros and expand properly, where previously the expansion would only work when no nesting was present.
See:
- `src/test/run-pass/macro-stmt_macro_in_expr_macro.rs`
- `src/test/run-pass/macro-nested_stmt_macro.rs`
This changes the interface of the MacResult trait. make_stmt has become make_stmts and now returns a vector, rather than a single item. Plugin writers who were implementing MacResult will have breakage, as well as anyone using MacEager::stmt.
See:
- `src/libsyntax/ext/base.rs`
This also causes a minor difference in behavior to the diagnostics produced by certain malformed macros.
See:
- `src/test/compile-fail/macro-incomplete-parse.rs`
Implements pop() on SmallVector, and uses it to expand the final semicolon
in a statement macro expansion more efficiently.
Corrects the placement of the call to fld.cx.bt_pop(). It must run
unconditionally to reverse the corresponding push.
Statement macros are now treated somewhat like item macros, in that a
statement macro can now expand into a series of statements, rather than
just a single statement.
This allows statement macros to be nested inside other kinds of macros and
expand properly, where previously the expansion would only work when no
nesting was present.
See: src/test/run-pass/macro-stmt_macro_in_expr_macro.rs
src/test/run-pass/macro-nested_stmt_macro.rs
This changes the interface of the MacResult trait. make_stmt has become
make_stmts and now returns a vector, rather than a single item. Plugin
writers who were implementing MacResult will have breakage, as well as
anyone using MacEager::stmt.
See: src/libsyntax/ext/base.rs
This also causes a minor difference in behavior to the diagnostics
produced by certain malformed macros.
See: src/test/compile-fail/macro-incomplete-parse.rs
- Functions in parser.rs return PResult<> rather than panicing
- Other functions in libsyntax call panic! explicitly for now if they rely on panicing behaviour.
- 'panictry!' macro added as scaffolding while converting panicing functions.
(This does the same as 'unwrap()' but is easier to grep for and turn into try!())
- Leaves panicing wrappers for the following functions so that the
quote_* macros behave the same:
- parse_expr, parse_item, parse_pat, parse_arm, parse_ty, parse_stmt
local only if matches `FUNDAMENTAL(LocalType)`, where `FUNDAMENTAL`
includes `&T` and types marked as fundamental (which includes `Box`).
Also apply these tests to negative reasoning.
This is a deprecated attribute that is slated for removal, and it also affects
all implementors of the trait. This commit removes the attribute and fixes up
implementors accordingly. The primary implementation which was lost was the
ability to compare `&[T]` and `Vec<T>` (in that order).
This change also modifies the `assert_eq!` macro to not consider both directions
of equality, only the one given in the left/right forms to the macro. This
modification is motivated due to the fact that `&[T] == Vec<T>` no longer
compiles, causing hundreds of errors in unit tests in the standard library (and
likely throughout the community as well).
Closes#19470
[breaking-change]
* Marks `#[stable]` the contents of the `std::convert` module.
* Added methods `PathBuf::as_path`, `OsString::as_os_str`,
`String::as_str`, `Vec::{as_slice, as_mut_slice}`.
* Deprecates `OsStr::from_str` in favor of a new, stable, and more
general `OsStr::new`.
* Adds unstable methods `OsString::from_bytes` and `OsStr::{to_bytes,
to_cstring}` for ergonomic FFI usage.
[breaking-change]
r? @alexcrichton
