gnome: Fix glib tool lookup consistency

It was not always using the pkg-config file.

mesonbuild/modules/gnome.py

@@ -203,6 +203,8 @@ if T.TYPE_CHECKING:
         vtail: T.Optional[str]
         depends: T.List[T.Union[BuildTarget, CustomTarget, CustomTargetIndex]]
 
+    ToolType = T.Union[Executable, ExternalProgram, OverrideProgram]
+
 
 # Differs from the CustomTarget version in that it straight defaults to True
 _BUILD_BY_DEFAULT: KwargInfo[bool] = KwargInfo(
@@ -317,6 +319,22 @@ class GnomeModule(ExtensionModule):
                      mlog.bold('https://github.com/mesonbuild/meson/issues/1387'),
                      once=True, fatal=False)
 
+    @staticmethod
+    def _find_tool(state: 'ModuleState', tool: str) -> 'ToolType':
+        tool_map = {
+            'gio-querymodules': 'gio-2.0',
+            'glib-compile-schemas': 'gio-2.0',
+            'glib-compile-resources': 'gio-2.0',
+            'gdbus-codegen': 'gio-2.0',
+            'glib-genmarshal': 'glib-2.0',
+            'glib-mkenums': 'glib-2.0',
+            'g-ir-scanner': 'gobject-introspection-1.0',
+            'g-ir-compiler': 'gobject-introspection-1.0',
+        }
+        depname = tool_map[tool]
+        varname = tool.replace('-', '_')
+        return state.find_tool(tool, depname, varname)
+
     @typed_kwargs(
         'gnome.post_install',
         KwargInfo('glib_compile_schemas', bool, default=False),
@@ -332,7 +350,7 @@ class GnomeModule(ExtensionModule):
         datadir_abs = os.path.join(state.environment.get_prefix(), state.environment.get_datadir())
         if kwargs['glib_compile_schemas'] and not self.install_glib_compile_schemas:
             self.install_glib_compile_schemas = True
-            prog = state.find_tool('glib-compile-schemas', 'gio-2.0', 'glib_compile_schemas')
+            prog = self._find_tool(state, 'glib-compile-schemas')
             schemasdir = os.path.join(datadir_abs, 'glib-2.0', 'schemas')
             script = state.backend.get_executable_serialisation([prog, schemasdir])
             script.skip_if_destdir = True
@@ -340,7 +358,7 @@ class GnomeModule(ExtensionModule):
         for d in kwargs['gio_querymodules']:
             if d not in self.install_gio_querymodules:
                 self.install_gio_querymodules.append(d)
-                prog = state.find_tool('gio-querymodules', 'gio-2.0', 'gio_querymodules')
+                prog = self._find_tool(state, 'gio-querymodules')
                 moduledir = os.path.join(state.environment.get_prefix(), d)
                 script = state.backend.get_executable_serialisation([prog, moduledir])
                 script.skip_if_destdir = True
@@ -390,8 +408,8 @@ class GnomeModule(ExtensionModule):
         self.__print_gresources_warning(state)
         glib_version = self._get_native_glib_version(state)
 
-        glib_compile_resources = state.find_program('glib-compile-resources')
-        cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]] = [glib_compile_resources, '@INPUT@']
+        glib_compile_resources = self._find_tool(state, 'glib-compile-resources')
+        cmd: T.List[T.Union['ToolType', str]] = [glib_compile_resources, '@INPUT@']
 
         source_dirs = kwargs['source_dir']
         dependencies = kwargs['dependencies']
@@ -481,7 +499,7 @@ class GnomeModule(ExtensionModule):
             raise MesonException('GResource header is installed yet export is not enabled')
 
         depfile: T.Optional[str] = None
-        target_cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]]
+        target_cmd: T.List[T.Union['ToolType', str]]
         if not mesonlib.version_compare(glib_version, gresource_dep_needed_version):
             # This will eventually go out of sync if dependencies are added
             target_cmd = cmd
@@ -780,8 +798,8 @@ class GnomeModule(ExtensionModule):
                                                             T.Union[Executable, 'ExternalProgram', 'OverrideProgram']]:
         if not self.gir_dep:
             self.gir_dep = state.dependency('gobject-introspection-1.0')
-            self.giscanner = state.find_tool('g-ir-scanner', 'gobject-introspection-1.0', 'g_ir_scanner')
-            self.gicompiler = state.find_tool('g-ir-compiler', 'gobject-introspection-1.0', 'g_ir_compiler')
+            self.giscanner = self._find_tool(state, 'g-ir-scanner')
+            self.gicompiler = self._find_tool(state, 'g-ir-compiler')
         return self.gir_dep, self.giscanner, self.gicompiler
 
     @functools.lru_cache(maxsize=None)
@@ -1230,7 +1248,7 @@ class GnomeModule(ExtensionModule):
         srcdir = os.path.join(state.build_to_src, state.subdir)
         outdir = state.subdir
 
-        cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]] = [state.find_program('glib-compile-schemas'), '--targetdir', outdir, srcdir]
+        cmd: T.List[T.Union['ToolType', str]] = [self._find_tool(state, 'glib-compile-schemas'), '--targetdir', outdir, srcdir]
         if state.subdir == '':
             targetname = 'gsettings-compile'
         else:
@@ -1602,7 +1620,7 @@ class GnomeModule(ExtensionModule):
                       kwargs: 'GdbusCodegen') -> ModuleReturnValue:
         namebase = args[0]
         xml_files: T.List[T.Union['FileOrString', build.GeneratedTypes]] = [args[1]] if args[1] else []
-        cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]] = [state.find_program('gdbus-codegen')]
+        cmd: T.List[T.Union['ToolType', str]] = [self._find_tool(state, 'gdbus-codegen')]
         cmd.extend(kwargs['extra_args'])
 
         # Autocleanup supported?
@@ -1912,8 +1930,8 @@ class GnomeModule(ExtensionModule):
 
         return ModuleReturnValue([c_file, h_file], [c_file, h_file])
 
-    @staticmethod
     def _make_mkenum_impl(
+            self,
             state: 'ModuleState',
             sources: T.Sequence[T.Union[str, mesonlib.File, CustomTarget, CustomTargetIndex, GeneratedList]],
             output: str,
@@ -1922,8 +1940,8 @@ class GnomeModule(ExtensionModule):
             install: bool = False,
             install_dir: T.Optional[T.Sequence[T.Union[str, bool]]] = None,
             depends: T.Optional[T.Sequence[T.Union[CustomTarget, CustomTargetIndex, BuildTarget]]] = None
-            ) -> CustomTarget:
-        real_cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]] = [state.find_program(['glib-mkenums', 'mkenums'])]
+            ) -> build.CustomTarget:
+        real_cmd: T.List[T.Union[str, 'ToolType']] = [self._find_tool(state, 'glib-mkenums')]
         real_cmd.extend(cmd)
         _install_dir = install_dir or state.environment.coredata.get_option(mesonlib.OptionKey('includedir'))
         assert isinstance(_install_dir, str), 'for mypy'
@@ -1968,7 +1986,7 @@ class GnomeModule(ExtensionModule):
 
         new_genmarshal = mesonlib.version_compare(self._get_native_glib_version(state), '>= 2.53.3')
 
-        cmd: T.List[T.Union[ExternalProgram, Executable, OverrideProgram, str]] = [state.find_program('glib-genmarshal')]
+        cmd: T.List[T.Union['ToolType', str]] = [self._find_tool(state, 'glib-genmarshal')]
         if kwargs['prefix']:
             cmd.extend(['--prefix', kwargs['prefix']])
         if kwargs['extra_args']: