Unlike the relatively non-invasive old way of capturing stdout/stderr,
this new way is also able to capture output from C's stdlib functions
such as `printf`. This is done by redirecting stdout and stderr file
descriptors to a file, and then reading this file back.
This approach has two sizeable drawbacks:
1) Performance, obviously. Previously an installed capture made the
program run faster (as long as it was then discarded), because a call
to `std::cout` did not result in text output to the console. This new
capture method in fact forces disk IO. While it is likely that any
modern OS will keep this file in memory-cache and might never actually
issue the IO to the backing storage, it is still a possibility and
calls to the file system are not free.
2) Nonportability. While POSIX is usually assumed portable, and this
implementation relies only on a very common parts of it, it is no
longer standard C++ (or just plain C) and thus might not be available
on some obscure platforms. Different C libs might also implement the
relevant functions in a less-than-useful ways (e.g. MS's `tmpfile`
generates a temp file inside system folder, so it will not work
without elevated privileges and thus is useless).
These two drawbacks mean that, at least for now, the new capture is
opt-in. To opt-in, `CATCH_CONFIG_EXPERIMENTAL_REDIRECT` needs to be
defined in the implementation file.
Closes#1243
std::isalnum expects an int in the range of unsigned char or -1 (EOF),
otherwise it exhibits undefined behavior. Casting from char to unsigned
char avoids this.
MSVC warns about this when compiling with /analyze.
Catch2's documentation promises that listeners are called _before_
reporters, but because of the previous implementation, they were
called _after_ reporters. This commit fixes that.
Closes#1234
The fix leaves an open question: should we keep treating refs
to static array of chars as strings, or should we instead
use `strnlen` to check if it is null-terminated within the buffer
Fixes#1238
Specific platforms (e.g. TDM-GCC) can have terrible timer resolution,
and our checking code will then loop for an inordinate amount of time.
This change will make it so that the calibration gives up after 3
seconds and just uses the already measured values.
This leaves one open question, how to signal that the resolution
is terrible and benchmarking should not happen?
Fixes#1237
There are still some holes, e.g. we leave surrogate pairs be
even though they are not a part of valid UTF-8, but this might
be for the better -- WTF-8 does support surrogate pairs inside
text.
Closes#1207
DJGPP cross compiler is targeting DOS which does not support POSIX
signals. Probably for the same reason (targeting DOS) this compiler
does not support wide characters.
This allows reducing the amount of friends needed for its interface
and some extra tricks later.
The bad part is that the pointer can become invalidated via
calls to other StringRef's public methods, but c'est la vie.
To prevent bugs with stitching system headers inside Catch,
the proxy header is responsible for guarding against inclusion
on Linux, rather than the includers.
Might be related to #1197
