Vala: fixes to gresource handling (#12418)

* Vala: depend on gresources

Valac uses gresource at compile time to look up .ui files

* Automatically pass `--gresourcesdir` to valac

* gnome.compile_resources: clean up duplicate paths better

* Add a test for improved gresouce handling

7 files changed, 70 insertions, 3 deletions

diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 0e1413f..3143dff 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -1691,11 +1691,21 @@ class NinjaBackend(backends.Backend):
                 # Install GIR to default location if requested by user
                 if len(target.install_dir) > 3 and target.install_dir[3] is True:
                     target.install_dir[3] = os.path.join(self.environment.get_datadir(), 'gir-1.0')
-        # Detect gresources and add --gresources arguments for each
+        # Detect gresources and add --gresources/--gresourcesdir arguments for each
+        gres_dirs = []
         for gensrc in other_src[1].values():
             if isinstance(gensrc, modules.GResourceTarget):
                 gres_xml, = self.get_custom_target_sources(gensrc)
                 args += ['--gresources=' + gres_xml]
+                for source_dir in gensrc.source_dirs:
+                    gres_dirs += [os.path.join(self.get_target_dir(gensrc), source_dir)]
+                # Ensure that resources are built before vala sources
+                # This is required since vala code using [GtkTemplate] effectively depends on .ui files
+                # GResourceHeaderTarget is not suitable due to lacking depfile
+                gres_c, = gensrc.get_outputs()
+                extra_dep_files += [os.path.join(self.get_target_dir(gensrc), gres_c)]
+        for gres_dir in OrderedSet(gres_dirs):
+            args += [f'--gresourcesdir={gres_dir}']
         dependency_vapis = self.determine_dep_vapis(target)
         extra_dep_files += dependency_vapis
         extra_dep_files.extend(self.get_target_depend_files(target))
diff --git a/mesonbuild/modules/__init__.py b/mesonbuild/modules/__init__.py
index 90a7f09..17b3631 100644
--- a/mesonbuild/modules/__init__.py
+++ b/mesonbuild/modules/__init__.py
@@ -254,7 +254,7 @@ class ModuleReturnValue:
         self.new_objects: T.List[T.Union['TYPE_var', 'mesonlib.ExecutableSerialisation']] = new_objects
 
 class GResourceTarget(build.CustomTarget):
-    pass
+    source_dirs: T.List[str] = []
 
 class GResourceHeaderTarget(build.CustomTarget):
     pass
diff --git a/mesonbuild/modules/gnome.py b/mesonbuild/modules/gnome.py
index 32df2a6..9d6c132 100644
--- a/mesonbuild/modules/gnome.py
+++ b/mesonbuild/modules/gnome.py
@@ -448,7 +448,10 @@ class GnomeModule(ExtensionModule):
         # Always include current directory, but after paths set by user
         source_dirs.append(os.path.join(state.build_to_src, state.subdir))
 
-        for source_dir in OrderedSet(source_dirs):
+        # Clean up duplicate directories
+        source_dirs = list(OrderedSet(os.path.normpath(dir) for dir in source_dirs))
+
+        for source_dir in source_dirs:
             cmd += ['--sourcedir', source_dir]
 
         if kwargs['c_name']:
@@ -507,6 +510,7 @@ class GnomeModule(ExtensionModule):
             install_dir=[kwargs['install_dir']] if kwargs['install_dir'] else [],
             install_tag=['runtime'],
         )
+        target_c.source_dirs = source_dirs
 
         if gresource: # Only one target for .gresource files
             return ModuleReturnValue(target_c, [target_c])
diff --git a/test cases/vala/28 generated ui file/TestBox.ui.in b/test cases/vala/28 generated ui file/TestBox.ui.in
new file mode 100644
index 0000000..bf5c831
--- /dev/null
+++ b/test cases/vala/28 generated ui file/TestBox.ui.in
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <requires lib="gtk" version="3.0"/>
+  <template class="TestBox" parent="GtkBox">
+  </template>
+</interface>
diff --git a/test cases/vala/28 generated ui file/meson.build b/test cases/vala/28 generated ui file/meson.build
new file mode 100644
index 0000000..fbf9840
--- /dev/null
+++ b/test cases/vala/28 generated ui file/meson.build
@@ -0,0 +1,34 @@
+project('demo', 'c', 'vala')
+
+gnome = import('gnome', required: false)
+
+if not gnome.found()
+  error('MESON_SKIP_TEST: gnome module not supported')
+endif
+
+deps = [
+  dependency('glib-2.0', version : '>=2.50'),
+  dependency('gobject-2.0'),
+  dependency('gtk+-3.0'),
+]
+
+ui_tgt = custom_target(
+  input: 'TestBox.ui.in',
+  output:  'TestBox.ui',
+  command: [find_program('cat')],
+  feed: true,
+  capture: true,
+)
+
+resources = gnome.compile_resources('test-resources',
+  'test.gresource.xml',
+  c_name: 'test_res',
+  dependencies: ui_tgt,
+)
+
+executable(
+  'demo',
+  'test.vala',
+  resources,
+  dependencies: deps,
+)
diff --git a/test cases/vala/28 generated ui file/test.gresource.xml b/test cases/vala/28 generated ui file/test.gresource.xml
new file mode 100644
index 0000000..382b951
--- /dev/null
+++ b/test cases/vala/28 generated ui file/test.gresource.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<gresources>
+  <gresource prefix="/com/mesonbuild/test">
+    <file>TestBox.ui</file>
+  </gresource>
+</gresources>
diff --git a/test cases/vala/28 generated ui file/test.vala b/test cases/vala/28 generated ui file/test.vala
new file mode 100644
index 0000000..36f565b
--- /dev/null
+++ b/test cases/vala/28 generated ui file/test.vala
@@ -0,0 +1,7 @@
+[GtkTemplate (ui = "/com/mesonbuild/test/TestBox.ui")]
+class TestBox: Gtk.Box {
+}
+
+int main() {
+    return 0;
+}