Fix configuration inheritance for configurations specified in the LSP settings (#13285)

crates/ruff_server/src/session/index/ruff_settings.rs

@@ -340,7 +340,7 @@ impl<'a> ConfigurationTransformer for EditorConfigurationTransformer<'a> {
 
         // Merge in the editor-specified configuration file, if it exists.
         let editor_configuration = if let Some(config_file_path) = configuration {
-            match open_configuration_file(&config_file_path, project_root) {
+            match open_configuration_file(&config_file_path) {
                 Ok(config_from_file) => editor_configuration.combine(config_from_file),
                 Err(err) => {
                     tracing::error!("Unable to find editor-specified configuration file: {err}");
@@ -363,11 +363,18 @@ impl<'a> ConfigurationTransformer for EditorConfigurationTransformer<'a> {
     }
 }
 
-fn open_configuration_file(
-    config_path: &Path,
-    project_root: &Path,
-) -> crate::Result<Configuration> {
-    let options = ruff_workspace::pyproject::load_options(config_path)?;
-
-    Configuration::from_options(options, Some(config_path), project_root)
+fn open_configuration_file(config_path: &Path) -> crate::Result<Configuration> {
+    ruff_workspace::resolver::resolve_configuration(
+        config_path,
+        Relativity::Parent,
+        &IdentityTransformer,
+    )
+}
+
+struct IdentityTransformer;
+
+impl ConfigurationTransformer for IdentityTransformer {
+    fn transform(&self, config: Configuration) -> Configuration {
+        config
+    }
 }

crates/ruff_workspace/src/pyproject.rs

@@ -140,7 +140,7 @@ pub fn find_user_settings_toml() -> Option<PathBuf> {
 }
 
 /// Load `Options` from a `pyproject.toml` or `ruff.toml` file.
-pub fn load_options<P: AsRef<Path>>(path: P) -> Result<Options> {
+pub(super) fn load_options<P: AsRef<Path>>(path: P) -> Result<Options> {
     if path.as_ref().ends_with("pyproject.toml") {
         let pyproject = parse_pyproject_toml(&path)?;
         let mut ruff = pyproject

crates/ruff_workspace/src/resolver.rs

@@ -263,7 +263,7 @@ pub trait ConfigurationTransformer {
 // configuration file extends another in the same path, we'll re-parse the same
 // file at least twice (possibly more than twice, since we'll also parse it when
 // resolving the "default" configuration).
-fn resolve_configuration(
+pub fn resolve_configuration(
     pyproject: &Path,
     relativity: Relativity,
     transformer: &dyn ConfigurationTransformer,