6 Commits

Author SHA1 Message Date
Louis Dionne
6a54dfbfe5 [libc++][NFC] Add missing license headers
Also standardize the license comment in several files where it was
different from what we normally do.
2024-07-31 12:58:09 -04:00
Mark de Wever
402eb2ef09 [libc++][format] Improves diagnostics.
Improves both the compile-time and run-time errors.
At compile-time it does a bit more work to get more specific errors.
This could be done at run-time too, but that has a performance penalty.
Since it's expected most use-cases use format* instead of vformat* the
compile-time errors are more common.

For example when using

  std::format_to("{:-c}", 42);

Before compile output would contain

  std::__throw_format_error("The format-spec should consume the input or end with a '}'");

Now it contains

  std::__throw_format_error("The format specifier does not allow the sign option");

Given a better indication the sign option is not allowed. Note the
output is still not user-friendly; C++ doesn't have good facilities to
generate nice messages from the library.

In general all messages have been reviewed and improved, using a more
consistent style and using less terms used in the standard. For example

  format-spec -> format specifier
  arg-id -> argument index

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D152624
2023-07-18 21:11:12 +02:00
Mark de Wever
a0ffeccc70 [libc++][format] Improves run-time diagnostics.
After parsing a std-format-spec it's validated, depending on the type used some
format options are not allowed. This improves the error messages in the
exceptions thrown upon failure.

Depends on D155364

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D155366
2023-07-18 21:01:52 +02:00
Mark de Wever
3f65f71833 [libc++][print] Adds FILE functions.
Drive-by fix to make sure the __retarget_buffer works correctly whan
using a hint of 1. This was discovered in one of the new tests.

Drive-by fixes __retarget_buffer when initialized with size 1.

Implements parts of
- P2093R14 Formatted output
- P2539R4  Should the output of std::print to a terminal be
           synchronized with the underlying stream?

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D150044
2023-07-18 20:07:11 +02:00
Louis Dionne
520c7fbbd0 [libc++] Mark slow tests as unsupported on GCC
Some tests in our test suite are unbelievably slow on GCC due to the
use of the always_inline attribute. See [1] for more details.

This patch introduces the GCC-ALWAYS_INLINE-FIXME lit feature to
disable tests that are plagued by that issue. At the same time, it
moves several existing tests from ad-hoc `UNSUPPORTED: gcc-12` markup
to the new GCC-ALWAYS_INLINE-FIXME feature, and marks the slowest tests
reported by the CI as `UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME`.

[1]: https://discourse.llvm.org/t/rfc-stop-supporting-extern-instantiations-with-gcc/71277/1

Differential Revision: https://reviews.llvm.org/D152736
2023-06-13 10:20:30 -07:00
Mark de Wever
5db033e204 [libc++][format] Improves fill character.
The main change is to allow a UCS scalar value as fill character.
Especially for char based formatting this increase the number of valid
characters. Originally this was to be expected ABI breaking, however the
current change does not seem to break the ABI.

Implements
- P2572 std::format() fill character allowances

Depends on D144499

Reviewed By: ldionne, tahonermann, #libc

Differential Revision: https://reviews.llvm.org/D144742
2023-05-19 17:20:50 +02:00