Workaround for a meson bug: https://github.com/mesonbuild/meson/issues/15093

diff --git i/tests/project/meson.build w/tests/project/meson.build
index f409198d..b582d83b 100644
--- i/tests/project/meson.build
+++ w/tests/project/meson.build
@@ -45,7 +45,7 @@ foreach t : tests
     endif

     test_source = props.get('source_root', meson.current_source_dir()) / name
-    kwargs = props.get('kwargs', {})
+    kwargs = props.get('kwargs_', {})
     suites = ['project', name.split('/')[0]]

     # skip objc tests on non darwin platforms
diff --git i/subprojects/meson-tests/meson.build w/subprojects/meson-tests/meson.build
index 861e57b..eb540a2 100644
--- i/subprojects/meson-tests/meson.build
+++ w/subprojects/meson-tests/meson.build
@@ -252,7 +252,7 @@ foreach t : [
     ['common/235 invalid standard overridden to valid'],
     [
         'common/236 proper args splitting',
-        {'kwargs': {'env': {'CFLAGS': '-DFOO -DBAR'}}},
+        {'kwargs_': {'env': {'CFLAGS': '-DFOO -DBAR'}}},
     ],
     ['common/237 fstrings'],
     ['common/238 dependency include_type inconsistency'],