Avoid creation of a temporary probe file for newer compilers

[wilzbach]

When I chated with @RazvanN7 today, he complained about DUB creating a lot of temporary probing files in his current working directory.
A quick look at the code revealed that DUB uses this probing hack to extract information
from DMD. Since dlang/dmd#6880 (2.076.0), it's possible
to avoid the need of creating a temporary file for this hack.
Of course, it would be better to read this file from the compiler directly...

[dlang-bot]

Thanks for your pull request, @wilzbach!

[wilzbach]

Of course we could also remove the temp file after the exit of the current scope.

[MartinNowak]

Temp files get deleted at the end of the run, would be better to make that mechanism more reliable instead of increasing the complexity for that single task.

dub/source/dub/internal/utils.d

Lines 40 to 47 in 79475c0

	NativePath getTempFile(string prefix, string extension = null)
	{
	import std.uuid : randomUUID;
	auto path = getTempDir() ~ (prefix ~ "-" ~ randomUUID.toString() ~ extension);
	temporary_files ~= path;
	return path;
	}

I'd guess the main source for the remaining temp files is dub's missing CTRL+C sigint handling, in particular in combination with dub run where you want to exit the child process, but terminate the parent instead.

[wilzbach]

FYI: the new JSON API (e.g. dmd -Xi=compilerInfo -Xf=- has been released with 2.079 and we should be able to use it for new LDC + DMD compilers.

See also: https://dlang.org/changelog/2.079.0.html#json_includes