hotdoc: Fix has_extensions when several extensions are passed in

mesonbuild/modules/hotdoc.py

@@ -379,7 +379,7 @@ class HotDocModule(ExtensionModule):
 
     @noKwargs
     def has_extensions(self, state, args, kwargs):
-        res = self.hotdoc.run_hotdoc(['--has-extension'] + args) == 0
+        res = self.hotdoc.run_hotdoc(['--has-extension=%s' % extension for extension in args]) == 0
         return ModuleReturnValue(res, [res])
 
     def generate_doc(self, state, args, kwargs):

test cases/frameworks/23 hotdoc/meson.build

@@ -7,3 +7,9 @@ endif
 
 subdir('doc')
 
+assert(hotdoc.has_extensions(['gi-extension']) == true,
+  'GI extension should always be found.')
+
+assert(hotdoc.has_extensions(['gi-extension', 'no-way-you-exist-extension']) == false,
+  'A hotdoc extension called "no-way-you-exist-extension" should never be found.')
+