test: Test loading provider plugins

tests/meson.build

@@ -12,11 +12,13 @@ test_env = [
 
 test_cflags = [
   '-fPIE',
-  '-DFOR_TESTING',
   '-Wno-error=deprecated-declarations',
   '-DPLUGIN_BUILDDIR="@0@"'.format(full_calls_plugin_builddir),
 ]
 
+test_cflags_with_test_define = test_cflags
+test_cflags_with_test_define +=  [ '-DFOR_TESTING' ]
+
 test_link_args = [
   '-fPIC',
 ]
@@ -44,7 +46,7 @@ foreach test : tests
   t = executable(name, test_sources,
                  calls_sources, dummy_sources, calls_enum_sources, calls_resources,
                  wl_proto_sources, wayland_sources,
-                 c_args : test_cflags,
+                 c_args : test_cflags_with_test_define,
                  link_args: test_link_args,
                  link_with : calls_vala,
                  dependencies: calls_deps,
@@ -71,5 +73,19 @@ t = executable('manager', test_sources,
                 )
 test('manager', t, env: test_env)
 
+test_sources = [ 'test-plugins.c' ]
+
+t = executable('plugins', test_sources,
+                 calls_sources, calls_enum_sources, calls_resources,
+                 wl_proto_sources, wayland_sources,
+                 c_args : test_cflags,
+                 link_args: test_link_args,
+                 link_with : calls_vala,
+                 dependencies: calls_deps,
+                 include_directories : [
+                   calls_includes
+                 ]
+                )
+test('plugins', t, env: test_env)
 
 endif