Add tests to cover these cases:
* run as regular CMake module, in NORMAL_MODE (expected to fail);
* run as CMake script in SCRIPT_MODE (expected to exit with given code);
* run as CMake script that `include()`-s another script with EXIT subcommand;
* run as CMake script which EVAL-uates EXIT subcommand via
`cmake_language(EVAL CODE "<cmake code>")`.
Fixes: #23162
The new sub-command writes a string representation of the
current log level to the output variable given to the
sub-command.
Given that the log-level might be set either via the --log-level
command line option or via the CMAKE_MESSAGE_LOG_LEVEL
cache / regular variables, the priority for each of the log level
sources is as follows, with the first one being the highest:
1) --log-level
2) CMAKE_MESSAGE_LOG_LEVEL regular variable
3) CMAKE_MESSAGE_LOG_LEVEL cache variable
4) default log level (STATUS)
Fixes: #23572
Tools using the json-v1 format might want to trace stack frames across
different `CMakeLists.txt` files, in order to, for example, provide
stacktraces that span from the top-level `CMakeLists.txt` in a
project. One would think that `frame` lets you do that, but it
doesn't, because it tells you the depth of the stack within the
current `CMakeLists.txt`, so it gets reset across calls to
`add_subdirectory`.
The solution involves adding a field with a "global frame". This value
gets incremented on calls to `add_subdirectory`, which makes it easier
for tools to reconstruct "global stacktraces".
I considered changing the current "frame" value, but I didn't because
it would be a breaking change. I cannot think of any use-case where
"frame" is more useful to "global-frame", but maybe I'm missing
something.
Brad King