This adds a new keyword argument to the init method, `allow_fail`. When
set to True (default is False) then a failure to configure is not an
error, and output is still returned. This can be useful for cases where
we expect initialization to fail, and want to check the output.
There are two problems with having this in the try/except block. The
first is that both of the if statements will raise, and the except
statement cathces `Exception`, so it catches these two cases, prints a
message that we either don't want or already printed, then re-raises.
We don't actually want to do anything with the open()ed file, just
immediately close it.
The CalledProcessError doesn't have its return returncode checked
here, even though other code with the same type of context manager does.
In the case main->subp->subsubp, if subsubp succeed to configure but
subp subsequentially fails, subsubp is still being built but its summary
was missing.
Meson already works like that, except in do_copydir() that requires
absolute destdir. Better explicitly support that instead of leaving it
undefined and unconsistent.
Xavier Claessens
Dylan Baker
Eli Schwartz
Jussi Pakkanen
lilinzhe
Alois Wohlschlager