Provide a Github Action Matrix build verification

[laeubi]

As SWT has platformspecific code it would be good to check the compile on each of those.

I have started creating one (see https://github.com/laeubi/eclipse.platform.swt/actions/workflows/maven.yml) but running into trouble find out what are the right parameters, I used https://wiki.eclipse.org/SWT/Developer_Guide#Build_SWT but it is not very informative (or I don't understand it) in regards to expected build parameters.

While I can get those from the CI build for linux I had to guess them for mac/windows, but it seems my guess is wrong I always get:

Error: Cannot resolve project dependencies:
Error: You requested to install 'org.eclipse.equinox.p2.iu; org.eclipse.swt.tests.fragments.feature.feature.group 0.0.0' but it could not be found

The buildfile could be found here: https://github.com/laeubi/eclipse.platform.swt/pull/1/files

it creates a matrix and defines the following for each:

• { os: ubuntu-latest, native: gtk.linux.x86_64 }
• { os: windows-latest, native: win32.win32.x86_64 }
• { os: macos-latest, native: cocoa.macosx.x86_64}

what the is passed to the build as -Dnative=${{ matrix.config.native }} but it seems either the id is wrong or I need to setup something for the other environments.

[laeubi]

I also find https://www.eclipse.org/swt/swt_win_native.php but it does not mention maven and seems a bit outdated as well (JDK8?).

[laeubi]

This is done now see https://github.com/eclipse-platform/eclipse.platform.swt/actions/workflows/maven.yml