In the case the main project set a subproject for a dependency another
subprojects uses, that other subproject should rather use the first
subproject rather that using native dependency.
For example in gst-all we set all GStreamer modules as subprojects
and, gst-plugins-base is set after gstreamer core, and
we want gst-plugins-base to always use GStreamer core from the subproject
and not the possibly avalaible native one.
And remove the InternalDependencyHolder class.
In some cases we need to know the type of dependency we are
dealing with. For example in GStreamer if the dependency
is not an internal one, then we need to get some env var
from pkg-config to know where to find some plugins necessary
to run some tests.
It is extremely common to need to know within a given dependency if
a given header, symbol, member, function, etc exists that cannot be
determined from the version number alone.
Without passing dependency objects to the various compiler/linker
checks and with many libraries headers/libraries being located in
their own subdirs of the standard prefix, the check for the library
would not find the header/function/symbol/etc.
This commit allows passing dependency objects to the compiler checks so
that the test program can be compiled/linked/run with the necessary
compilation and/or linking flags for that library.
Also add new tests for the platform-specific and compiler-specific
versioning scheme.
A rough summary is:
1. A bug in how run_tests.py:validate_install checked for files has been
fixed. Earlier it wasn't checking the install directory properly.
2. Shared libraries are no longer installed in common tests, and the
library name/path testing is now done in platform-specific tests.
3. Executables are now always called something?exe in the
installed_files.txt file, and the suffix automatically corrected
depending on the platform.
4. If a test installs a file called 'no-installed-files', the installed
files for that test are not validated. This is required to implement
compiler-specific tests for library names/paths such as MSVC vs MinGW
5. The platform-specific file renaming in run_tests.py has been mostly
removed since it is broken for shared libraries and isn't needed for
static libraries.
6. run_tests.py now reports all missing and extra files. The logic for
finding these has been reworked.