install_scripts used to replace @BUILD_ROOT@ and @SOURCE_ROOT@ but it
was not documented and got removed in Meson 0.58.0. gnome.gtkdoc() was
relying on that behaviour, but it has always been broken in the case the
source or build directory contains spaces.
Fix this by changing get_include_args() to substitue paths directly
which will then get escaped correctly.
Add a unit test that builds GObject documentation which is where this
issue has been spotted.
Fixes: #8744
D lang compilers have an option -release (or similar) which turns off
asserts, contracts, and other runtime type checking. This patch wires
that up to the b_ndebug flag.
Fixes#7082
The GtkDoc test has been extended to also test the inclusion of
generated files.
To test this, a new python script has been included which generates
a new docbook file which is included as content file.