Rename Red Knot (#17820)

crates/ty_project/src/metadata/configuration_file.rs

@@ -0,0 +1,69 @@
+use std::sync::Arc;
+
+use ruff_db::system::{System, SystemPath, SystemPathBuf};
+use thiserror::Error;
+
+use crate::metadata::value::ValueSource;
+
+use super::options::{Options, TyTomlError};
+
+/// A `ty.toml` configuration file with the options it contains.
+pub(crate) struct ConfigurationFile {
+    path: SystemPathBuf,
+    options: Options,
+}
+
+impl ConfigurationFile {
+    /// Loads the user-level configuration file if it exists.
+    ///
+    /// Returns `None` if the file does not exist or if the concept of user-level configurations
+    /// doesn't exist on `system`.
+    pub(crate) fn user(system: &dyn System) -> Result<Option<Self>, ConfigurationFileError> {
+        let Some(configuration_directory) = system.user_config_directory() else {
+            return Ok(None);
+        };
+
+        let ty_toml_path = configuration_directory.join("ty").join("ty.toml");
+
+        tracing::debug!(
+            "Searching for a user-level configuration at `{path}`",
+            path = &ty_toml_path
+        );
+
+        let Ok(ty_toml_str) = system.read_to_string(&ty_toml_path) else {
+            return Ok(None);
+        };
+
+        match Options::from_toml_str(
+            &ty_toml_str,
+            ValueSource::File(Arc::new(ty_toml_path.clone())),
+        ) {
+            Ok(options) => Ok(Some(Self {
+                path: ty_toml_path,
+                options,
+            })),
+            Err(error) => Err(ConfigurationFileError::InvalidTyToml {
+                source: Box::new(error),
+                path: ty_toml_path,
+            }),
+        }
+    }
+
+    /// Returns the path to the configuration file.
+    pub(crate) fn path(&self) -> &SystemPath {
+        &self.path
+    }
+
+    pub(crate) fn into_options(self) -> Options {
+        self.options
+    }
+}
+
+#[derive(Debug, Error)]
+pub enum ConfigurationFileError {
+    #[error("{path} is not a valid `ty.toml`: {source}")]
+    InvalidTyToml {
+        source: Box<TyTomlError>,
+        path: SystemPathBuf,
+    },
+}