mformat: try to detect meson.format in parent directories

mesonbuild/mformat.py

@@ -975,9 +975,12 @@ def run(options: argparse.Namespace) -> int:
 
     sources: T.List[Path] = options.sources.copy() or [Path(build_filename)]
     if not options.configuration:
-        default_config_path = sources[0].parent / 'meson.format'
-        if default_config_path.exists():
-            options.configuration = default_config_path
+        current_path = Path.cwd()
+        for parent in [current_path] + list(current_path.parents):
+            target = parent / 'meson.format'
+            if target.exists() and target.is_file():
+                options.configuration = target
+
     formatter = Formatter(options.configuration, options.editor_config, options.recursive)
 
     while sources:

test cases/format/4 config/meson.build

@@ -4,6 +4,7 @@
 project('default format')
 
 meson_cmd = find_program('meson')
+meson_format = files('meson.format')
 meson_files = {
   'self' : files('meson.build'),
   'comments' : files('crazy_comments.meson'),
@@ -14,6 +15,6 @@ foreach name, f : meson_files
   test(
     name,
     meson_cmd,
-    args : [ 'format', '--check-only', f ],
+    args : [ 'format', '--check-only', f, '--configuration', meson_format ],
   )
 endforeach