doc: Run gtkdoc-check with unit tests

This has the side effect of always rebuilding the doc at each build when
gtk_doc option is enabled (not by default). Most importantly, this will
enable doc check on our CI.

.gitlab-ci.yml

@@ -53,6 +53,7 @@ fedora-x86_64:
             -Ddtrace=true
             -Dfam=true
             -Dinstalled_tests=true
+            -Dgtk_doc=true
             _build
     - ninja -C _build
     - mkdir -p _coverage

docs/reference/gio/meson.build

@@ -209,7 +209,8 @@ if get_option('gtk_doc')
       '--extra-dir=' + join_paths('gio', '..', 'glib', 'html'),
       '--extra-dir=' + join_paths('gio', '..', 'gobject', 'html'),
     ],
-    install: true
+    install: true,
+    check: true,
   )
 endif
 

docs/reference/glib/meson.build

@@ -88,7 +88,8 @@ if get_option('gtk_doc')
                fixxref_args: [
                  '--html-dir=' + docpath,
                ],
-               install: true)
+               install: true,
+               check: true)
 endif
 
 if get_option('man')

docs/reference/gobject/meson.build

@@ -50,7 +50,8 @@ if get_option('gtk_doc')
       '--html-dir=' + docpath,
       '--extra-dir=' + join_paths('gobject', '..', 'glib', 'html'),
     ],
-    install: true
+    install: true,
+    check: true,
   )
 endif