Review feedback

Author: MichaReiser

crates/red_knot_test/src/db.rs

@@ -28,29 +28,22 @@ impl Db {
         let rule_selection = RuleSelection::from_registry(default_lint_registry());
 
         Self {
-            system: MdtestSystem::in_memory(SystemPathBuf::from("/")),
+            system: MdtestSystem::in_memory(),
             storage: salsa::Storage::default(),
             vendored: red_knot_vendored::file_system().clone(),
             files: Files::default(),
             rule_selection: Arc::new(rule_selection),
         }
     }
 
-    pub(crate) fn reset_fs(&mut self) {
-        match &*self.system.0 {
-            MdtestSystemInner::InMemory(in_memory) => {
-                in_memory.fs().remove_all();
-            }
-            MdtestSystemInner::Os { .. } => {
-                self.system = MdtestSystem::in_memory(SystemPathBuf::from("/"));
-            }
-        }
-
+    pub(crate) fn use_os_system_with_temp_dir(&mut self, cwd: SystemPathBuf, temp_dir: TempDir) {
+        self.system.with_os(cwd, temp_dir);
         Files::sync_all(self);
     }
 
-    pub(crate) fn with_tempdir_fs(&mut self, cwd: SystemPathBuf, temp_dir: TempDir) {
-        self.system.with_os(cwd, temp_dir);
+    pub(crate) fn use_in_memory_system(&mut self) {
+        self.system.with_in_memory();
+        Files::sync_all(self);
     }
 
     pub(crate) fn create_directory_all(&self, path: &SystemPath) -> ruff_db::system::Result<()> {
@@ -122,10 +115,10 @@ enum MdtestSystemInner {
 }
 
 impl MdtestSystem {
-    fn in_memory(cwd: SystemPathBuf) -> Self {
-        Self(Arc::new(MdtestSystemInner::InMemory(InMemorySystem::new(
-            cwd,
-        ))))
+    fn in_memory() -> Self {
+        Self(Arc::new(MdtestSystemInner::InMemory(
+            InMemorySystem::default(),
+        )))
     }
 
     fn as_system(&self) -> &dyn WritableSystem {
@@ -142,6 +135,14 @@ impl MdtestSystem {
         });
     }
 
+    fn with_in_memory(&mut self) {
+        if let MdtestSystemInner::InMemory(in_memory) = &*self.0 {
+            in_memory.fs().remove_all();
+        } else {
+            self.0 = Arc::new(MdtestSystemInner::InMemory(InMemorySystem::default()));
+        }
+    }
+
     fn normalize_path<'a>(&self, path: &'a SystemPath) -> Cow<'a, SystemPath> {
         match &*self.0 {
             MdtestSystemInner::InMemory(_) => Cow::Borrowed(path),

crates/red_knot_test/src/lib.rs

@@ -57,9 +57,6 @@ pub fn run(
             Log::Filter(filter) => setup_logging_with_filter(filter),
         });
 
-        // Remove all files so that the db is in a "fresh" state.
-        db.reset_fs();
-
         if let Err(failures) = run_test(&mut db, relative_fixture_path, snapshot_path, &test) {
             any_failures = true;
             println!("\n{}\n", test.name().bold().underline());
@@ -104,16 +101,22 @@ fn run_test(
     snapshot_path: &Utf8Path,
     test: &parser::MarkdownTest,
 ) -> Result<(), Failures> {
-    if SystemKind::Os == test.configuration().system.unwrap_or_default() {
-        let dir = tempfile::TempDir::new().expect("Creating a temporary directory to succeed");
-        let root_path = dir
-            .path()
-            .canonicalize()
-            .expect("Canonicalizing to succeed");
-        let root_path = SystemPathBuf::from_path_buf(root_path)
-            .expect("Temp directory to be a valid UTF8 path");
-
-        db.with_tempdir_fs(root_path, dir);
+    // Initialize the system and remove all files and directories to reset the system to a clean state.
+    match test.configuration().system.unwrap_or_default() {
+        SystemKind::InMemory => {
+            db.use_in_memory_system();
+        }
+        SystemKind::Os => {
+            let dir = tempfile::TempDir::new().expect("Creating a temporary directory to succeed");
+            let root_path = dir
+                .path()
+                .canonicalize()
+                .expect("Canonicalizing to succeed");
+            let root_path = SystemPathBuf::from_path_buf(root_path)
+                .expect("Temp directory to be a valid UTF8 path");
+
+            db.use_os_system_with_temp_dir(root_path, dir);
+        }
     }
 
     let project_root = SystemPathBuf::from("/src");