[ty] Add --config-file CLI arg (#18083)

crates/ruff_benchmark/benches/ty.rs

@@ -78,7 +78,7 @@ fn setup_tomllib_case() -> Case {
 
     let src_root = SystemPath::new("/src");
     let mut metadata = ProjectMetadata::discover(src_root, &system).unwrap();
-    metadata.apply_cli_options(Options {
+    metadata.apply_options(Options {
         environment: Some(EnvironmentOptions {
             python_version: Some(RangedValue::cli(PythonVersion::PY312)),
             ..EnvironmentOptions::default()
@@ -224,7 +224,7 @@ fn setup_micro_case(code: &str) -> Case {
 
     let src_root = SystemPath::new("/src");
     let mut metadata = ProjectMetadata::discover(src_root, &system).unwrap();
-    metadata.apply_cli_options(Options {
+    metadata.apply_options(Options {
         environment: Some(EnvironmentOptions {
             python_version: Some(RangedValue::cli(PythonVersion::PY312)),
             ..EnvironmentOptions::default()

crates/ty/Cargo.toml

@@ -22,7 +22,7 @@ ty_server = { workspace = true }
 
 anyhow = { workspace = true }
 argfile = { workspace = true }
-clap = { workspace = true, features = ["wrap_help", "string"] }
+clap = { workspace = true, features = ["wrap_help", "string", "env"] }
 clap_complete_command = { workspace = true }
 colored = { workspace = true }
 countme = { workspace = true, features = ["enable"] }

crates/ty/docs/cli.md

@@ -47,7 +47,9 @@ ty check [OPTIONS] [PATH]...
 overriding a specific configuration option.</p>
 <p>Overrides of individual settings using this option always take precedence
 over all configuration files.</p>
-</dd><dt id="ty-check--error"><a href="#ty-check--error"><code>--error</code></a> <i>rule</i></dt><dd><p>Treat the given rule as having severity 'error'. Can be specified multiple times.</p>
+</dd><dt id="ty-check--config-file"><a href="#ty-check--config-file"><code>--config-file</code></a> <i>path</i></dt><dd><p>The path to a <code>ty.toml</code> file to use for configuration.</p>
+<p>While ty configuration can be included in a <code>pyproject.toml</code> file, it is not allowed in this context.</p>
+<p>May also be set with the <code>TY_CONFIG_FILE</code> environment variable.</p></dd><dt id="ty-check--error"><a href="#ty-check--error"><code>--error</code></a> <i>rule</i></dt><dd><p>Treat the given rule as having severity 'error'. Can be specified multiple times.</p>
 </dd><dt id="ty-check--error-on-warning"><a href="#ty-check--error-on-warning"><code>--error-on-warning</code></a></dt><dd><p>Use exit code 1 if there are any warning-level diagnostics</p>
 </dd><dt id="ty-check--exit-zero"><a href="#ty-check--exit-zero"><code>--exit-zero</code></a></dt><dd><p>Always use exit code 0, even when there are error-level diagnostics</p>
 </dd><dt id="ty-check--extra-search-path"><a href="#ty-check--extra-search-path"><code>--extra-search-path</code></a> <i>path</i></dt><dd><p>Additional path to use as a module-resolution source (can be passed multiple times)</p>

crates/ty/src/args.rs

@@ -107,6 +107,12 @@ pub(crate) struct CheckCommand {
     #[clap(flatten)]
     pub(crate) config: ConfigsArg,
 
+    /// The path to a `ty.toml` file to use for configuration.
+    ///
+    /// While ty configuration can be included in a `pyproject.toml` file, it is not allowed in this context.
+    #[arg(long, env = "TY_CONFIG_FILE", value_name = "PATH")]
+    pub(crate) config_file: Option<SystemPathBuf>,
+
     /// The format to use for printing diagnostic messages.
     #[arg(long)]
     pub(crate) output_format: Option<OutputFormat>,

crates/ty/src/lib.rs

@@ -23,7 +23,7 @@ use ruff_db::diagnostic::{Diagnostic, DisplayDiagnosticConfig, Severity};
 use ruff_db::max_parallelism;
 use ruff_db::system::{OsSystem, SystemPath, SystemPathBuf};
 use salsa::plumbing::ZalsaDatabase;
-use ty_project::metadata::options::Options;
+use ty_project::metadata::options::ProjectOptionsOverrides;
 use ty_project::watch::ProjectWatcher;
 use ty_project::{Db, DummyReporter, Reporter, watch};
 use ty_project::{ProjectDatabase, ProjectMetadata};
@@ -102,13 +102,21 @@ fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
         .map(|path| SystemPath::absolute(path, &cwd))
         .collect();
 
-    let system = OsSystem::new(cwd);
+    let system = OsSystem::new(&cwd);
     let watch = args.watch;
     let exit_zero = args.exit_zero;
+    let config_file = args
+        .config_file
+        .as_ref()
+        .map(|path| SystemPath::absolute(path, &cwd));
 
-    let cli_options = args.into_options();
+    let mut project_metadata = match &config_file {
-    let mut project_metadata = ProjectMetadata::discover(&project_path, &system)?;
+        Some(config_file) => ProjectMetadata::from_config_file(config_file.clone(), &system)?,
-    project_metadata.apply_cli_options(cli_options.clone());
+        None => ProjectMetadata::discover(&project_path, &system)?,
+    };
+
+    let options = args.into_options();
+    project_metadata.apply_options(options.clone());
     project_metadata.apply_configuration_files(&system)?;
 
     let mut db = ProjectDatabase::new(project_metadata, system)?;
@@ -117,7 +125,8 @@ fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
         db.project().set_included_paths(&mut db, check_paths);
     }
 
-    let (main_loop, main_loop_cancellation_token) = MainLoop::new(cli_options);
+    let project_options_overrides = ProjectOptionsOverrides::new(config_file, options);
+    let (main_loop, main_loop_cancellation_token) = MainLoop::new(project_options_overrides);
 
     // Listen to Ctrl+C and abort the watch mode.
     let main_loop_cancellation_token = Mutex::new(Some(main_loop_cancellation_token));
@@ -178,11 +187,13 @@ struct MainLoop {
     /// The file system watcher, if running in watch mode.
     watcher: Option<ProjectWatcher>,
 
-    cli_options: Options,
+    project_options_overrides: ProjectOptionsOverrides,
 }
 
 impl MainLoop {
-    fn new(cli_options: Options) -> (Self, MainLoopCancellationToken) {
+    fn new(
+        project_options_overrides: ProjectOptionsOverrides,
+    ) -> (Self, MainLoopCancellationToken) {
         let (sender, receiver) = crossbeam_channel::bounded(10);
 
         (
@@ -190,7 +201,7 @@ impl MainLoop {
                 sender: sender.clone(),
                 receiver,
                 watcher: None,
-                cli_options,
+                project_options_overrides,
             },
             MainLoopCancellationToken { sender },
         )
@@ -340,7 +351,7 @@ impl MainLoop {
                 MainLoopMessage::ApplyChanges(changes) => {
                     revision += 1;
                     // Automatically cancels any pending queries and waits for them to complete.
-                    db.apply_changes(changes, Some(&self.cli_options));
+                    db.apply_changes(changes, Some(&self.project_options_overrides));
                     if let Some(watcher) = self.watcher.as_mut() {
                         watcher.update(db);
                     }

crates/ty/tests/cli.rs

@@ -1700,6 +1700,63 @@ fn check_conda_prefix_var_to_resolve_path() -> anyhow::Result<()> {
     ----- stderr -----
     WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
     ");
+
+    Ok(())
+}
+
+#[test]
+fn config_file_override() -> anyhow::Result<()> {
+    // Set `error-on-warning` to true in the configuration file
+    // Explicitly set `--warn unresolved-reference` to ensure the rule warns instead of errors
+    let case = TestCase::with_files(vec![
+        ("test.py", r"print(x)  # [unresolved-reference]"),
+        (
+            "ty-override.toml",
+            r#"
+            [terminal]
+            error-on-warning = true
+            "#,
+        ),
+    ])?;
+
+    // Ensure flag works via CLI arg
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--config-file").arg("ty-override.toml"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Ensure the flag works via an environment variable
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").env("TY_CONFIG_FILE", "ty-override.toml"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
     Ok(())
 }
 

crates/ty/tests/file_watching.rs

@@ -10,7 +10,7 @@ use ruff_db::system::{
 };
 use ruff_db::{Db as _, Upcast};
 use ruff_python_ast::PythonVersion;
-use ty_project::metadata::options::{EnvironmentOptions, Options};
+use ty_project::metadata::options::{EnvironmentOptions, Options, ProjectOptionsOverrides};
 use ty_project::metadata::pyproject::{PyProject, Tool};
 use ty_project::metadata::value::{RangedValue, RelativePathBuf};
 use ty_project::watch::{ChangeEvent, ProjectWatcher, directory_watcher};
@@ -164,8 +164,12 @@ impl TestCase {
         Ok(all_events)
     }
 
-    fn apply_changes(&mut self, changes: Vec<ChangeEvent>) {
+    fn apply_changes(
-        self.db.apply_changes(changes, None);
+        &mut self,
+        changes: Vec<ChangeEvent>,
+        project_options_overrides: Option<&ProjectOptionsOverrides>,
+    ) {
+        self.db.apply_changes(changes, project_options_overrides);
     }
 
     fn update_options(&mut self, options: Options) -> anyhow::Result<()> {
@@ -180,7 +184,7 @@ impl TestCase {
         .context("Failed to write configuration")?;
 
         let changes = self.take_watch_changes(event_for_file("pyproject.toml"));
-        self.apply_changes(changes);
+        self.apply_changes(changes, None);
 
         if let Some(watcher) = &mut self.watcher {
             watcher.update(&self.db);
@@ -476,7 +480,7 @@ fn new_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     let foo = case.system_file(&foo_path).expect("foo.py to exist.");
 
@@ -499,7 +503,7 @@ fn new_ignored_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(case.system_file(&foo_path).is_ok());
     case.assert_indexed_project_files([bar_file]);
@@ -535,7 +539,7 @@ fn new_non_project_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("black.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(case.system_file(&black_path).is_ok());
 
@@ -576,7 +580,7 @@ fn new_files_with_explicit_included_paths() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("test2.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     let sub_a_file = case.system_file(&sub_a_path).expect("sub/a.py to exist");
 
@@ -621,7 +625,7 @@ fn new_file_in_included_out_of_project_directory() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("script2.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     let src_a_file = case.system_file(&src_a).unwrap();
     let outside_b_file = case.system_file(&outside_b_path).unwrap();
@@ -648,7 +652,7 @@ fn changed_file() -> anyhow::Result<()> {
 
     assert!(!changes.is_empty());
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 2')");
     case.assert_indexed_project_files([foo]);
@@ -671,7 +675,7 @@ fn deleted_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(!foo.exists(case.db()));
     case.assert_indexed_project_files([]);
@@ -703,7 +707,7 @@ fn move_file_to_trash() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(!foo.exists(case.db()));
     case.assert_indexed_project_files([]);
@@ -730,7 +734,7 @@ fn move_file_to_project() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     let foo_in_project = case.system_file(&foo_in_project)?;
 
@@ -755,7 +759,7 @@ fn rename_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("bar.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(!foo.exists(case.db()));
 
@@ -796,7 +800,7 @@ fn directory_moved_to_project() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("sub"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     let init_file = case
         .system_file(sub_new_path.join("__init__.py"))
@@ -853,7 +857,7 @@ fn directory_moved_to_trash() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("sub"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     // `import sub.a` should no longer resolve
     assert!(
@@ -916,7 +920,7 @@ fn directory_renamed() -> anyhow::Result<()> {
     // Linux and windows only emit an event for the newly created root directory, but not for every new component.
     let changes = case.stop_watch(event_for_file("sub"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     // `import sub.a` should no longer resolve
     assert!(
@@ -989,7 +993,7 @@ fn directory_deleted() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("sub"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     // `import sub.a` should no longer resolve
     assert!(
@@ -1035,7 +1039,7 @@ fn search_path() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("a.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(resolve_module(case.db().upcast(), &ModuleName::new_static("a").unwrap()).is_some());
     case.assert_indexed_project_files([case.system_file(case.project_path("bar.py")).unwrap()]);
@@ -1066,7 +1070,7 @@ fn add_search_path() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("a.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(resolve_module(case.db().upcast(), &ModuleName::new_static("a").unwrap()).is_some());
 
@@ -1213,7 +1217,7 @@ fn changed_versions_file() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("VERSIONS"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert!(resolve_module(case.db(), &ModuleName::new("os").unwrap()).is_some());
 
@@ -1267,7 +1271,7 @@ fn hard_links_in_project() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("foo.py"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 2')");
 
@@ -1338,7 +1342,7 @@ fn hard_links_to_target_outside_project() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(ChangeEvent::is_changed);
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 2')");
 
@@ -1377,7 +1381,7 @@ mod unix {
 
         let changes = case.stop_watch(event_for_file("foo.py"));
 
-        case.apply_changes(changes);
+        case.apply_changes(changes, None);
 
         assert_eq!(
             foo.permissions(case.db()),
@@ -1460,7 +1464,7 @@ mod unix {
 
         let changes = case.take_watch_changes(event_for_file("baz.py"));
 
-        case.apply_changes(changes);
+        case.apply_changes(changes, None);
 
         assert_eq!(
             source_text(case.db(), baz_file).as_str(),
@@ -1473,7 +1477,7 @@ mod unix {
 
         let changes = case.stop_watch(event_for_file("baz.py"));
 
-        case.apply_changes(changes);
+        case.apply_changes(changes, None);
 
         assert_eq!(
             source_text(case.db(), baz_file).as_str(),
@@ -1544,7 +1548,7 @@ mod unix {
 
         let changes = case.stop_watch(event_for_file("baz.py"));
 
-        case.apply_changes(changes);
+        case.apply_changes(changes, None);
 
         // The file watcher is guaranteed to emit one event for the changed file, but it isn't specified
         // if the event is emitted for the "original" or linked path because both paths are watched.
@@ -1658,7 +1662,7 @@ mod unix {
 
         let changes = case.stop_watch(event_for_file("baz.py"));
 
-        case.apply_changes(changes);
+        case.apply_changes(changes, None);
 
         assert_eq!(
             source_text(case.db(), baz_original_file).as_str(),
@@ -1715,7 +1719,7 @@ fn nested_projects_delete_root() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(ChangeEvent::is_deleted);
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     // It should now pick up the outer project.
     assert_eq!(case.db().project().root(case.db()), case.root_path());
@@ -1781,7 +1785,73 @@ fn changes_to_user_configuration() -> anyhow::Result<()> {
 
     let changes = case.stop_watch(event_for_file("ty.toml"));
 
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
+
+    let diagnostics = case.db().check_file(foo);
+
+    assert!(
+        diagnostics.len() == 1,
+        "Expected exactly one diagnostic but got: {diagnostics:#?}"
+    );
+
+    Ok(())
+}
+
+#[test]
+fn changes_to_config_file_override() -> anyhow::Result<()> {
+    let mut case = setup(|context: &mut SetupContext| {
+        std::fs::write(
+            context.join_project_path("pyproject.toml").as_std_path(),
+            r#"
+            [project]
+            name = "test"
+            "#,
+        )?;
+
+        std::fs::write(
+            context.join_project_path("foo.py").as_std_path(),
+            "a = 10 / 0",
+        )?;
+
+        std::fs::write(
+            context.join_project_path("ty-override.toml").as_std_path(),
+            r#"
+            [rules]
+            division-by-zero = "ignore"
+            "#,
+        )?;
+
+        Ok(())
+    })?;
+
+    let foo = case
+        .system_file(case.project_path("foo.py"))
+        .expect("foo.py to exist");
+    let diagnostics = case.db().check_file(foo);
+
+    assert!(
+        diagnostics.is_empty(),
+        "Expected no diagnostics but got: {diagnostics:#?}"
+    );
+
+    // Enable division-by-zero in the explicitly specified configuration with warning severity
+    update_file(
+        case.project_path("ty-override.toml"),
+        r#"
+        [rules]
+        division-by-zero = "warn"
+        "#,
+    )?;
+
+    let changes = case.stop_watch(event_for_file("ty-override.toml"));
+
+    case.apply_changes(
+        changes,
+        Some(&ProjectOptionsOverrides::new(
+            Some(case.project_path("ty-override.toml")),
+            Options::default(),
+        )),
+    );
 
     let diagnostics = case.db().check_file(foo);
 
@@ -1855,7 +1925,7 @@ fn rename_files_casing_only() -> anyhow::Result<()> {
     }
 
     let changes = case.stop_watch(event_for_file("Lib.py"));
-    case.apply_changes(changes);
+    case.apply_changes(changes, None);
 
     // Resolving `lib` should now fail but `Lib` should now succeed
     assert_eq!(

crates/ty_project/src/db/changes.rs

@@ -1,5 +1,5 @@
 use crate::db::{Db, ProjectDatabase};
-use crate::metadata::options::Options;
+use crate::metadata::options::ProjectOptionsOverrides;
 use crate::watch::{ChangeEvent, CreatedKind, DeletedKind};
 use crate::{Project, ProjectMetadata};
 use std::collections::BTreeSet;
@@ -12,10 +12,18 @@ use rustc_hash::FxHashSet;
 use ty_python_semantic::Program;
 
 impl ProjectDatabase {
-    #[tracing::instrument(level = "debug", skip(self, changes, cli_options))]
+    #[tracing::instrument(level = "debug", skip(self, changes, project_options_overrides))]
-    pub fn apply_changes(&mut self, changes: Vec<ChangeEvent>, cli_options: Option<&Options>) {
+    pub fn apply_changes(
+        &mut self,
+        changes: Vec<ChangeEvent>,
+        project_options_overrides: Option<&ProjectOptionsOverrides>,
+    ) {
         let mut project = self.project();
         let project_root = project.root(self).to_path_buf();
+        let config_file_override =
+            project_options_overrides.and_then(|options| options.config_file_override.clone());
+        let options =
+            project_options_overrides.map(|project_options| project_options.options.clone());
         let program = Program::get(self);
         let custom_stdlib_versions_path = program
             .custom_stdlib_search_path(self)
@@ -42,6 +50,14 @@ impl ProjectDatabase {
             tracing::trace!("Handle change: {:?}", change);
 
             if let Some(path) = change.system_path() {
+                if let Some(config_file) = &config_file_override {
+                    if config_file.as_path() == path {
+                        project_changed = true;
+
+                        continue;
+                    }
+                }
+
                 if matches!(
                     path.file_name(),
                     Some(".gitignore" | ".ignore" | "ty.toml" | "pyproject.toml")
@@ -170,10 +186,14 @@ impl ProjectDatabase {
         }
 
         if project_changed {
-            match ProjectMetadata::discover(&project_root, self.system()) {
+            let new_project_metadata = match config_file_override {
+                Some(config_file) => ProjectMetadata::from_config_file(config_file, self.system()),
+                None => ProjectMetadata::discover(&project_root, self.system()),
+            };
+            match new_project_metadata {
                 Ok(mut metadata) => {
-                    if let Some(cli_options) = cli_options {
+                    if let Some(cli_options) = options {
-                        metadata.apply_cli_options(cli_options.clone());
+                        metadata.apply_options(cli_options);
                     }
 
                     if let Err(error) = metadata.apply_configuration_files(self.system()) {

crates/ty_project/src/lib.rs

@@ -5,7 +5,7 @@ use crate::walk::{ProjectFilesFilter, ProjectFilesWalker};
 pub use db::{Db, ProjectDatabase};
 use files::{Index, Indexed, IndexedFiles};
 use metadata::settings::Settings;
-pub use metadata::{ProjectDiscoveryError, ProjectMetadata};
+pub use metadata::{ProjectMetadata, ProjectMetadataError};
 use ruff_db::diagnostic::{
     Annotation, Diagnostic, DiagnosticId, Severity, Span, SubDiagnostic, create_parse_diagnostic,
     create_unsupported_syntax_diagnostic,

crates/ty_project/src/metadata.rs

@@ -48,6 +48,29 @@ impl ProjectMetadata {
         }
     }
 
+    pub fn from_config_file(
+        path: SystemPathBuf,
+        system: &dyn System,
+    ) -> Result<Self, ProjectMetadataError> {
+        tracing::debug!("Using overridden configuration file at '{path}'");
+
+        let config_file = ConfigurationFile::from_path(path.clone(), system).map_err(|error| {
+            ProjectMetadataError::ConfigurationFileError {
+                source: Box::new(error),
+                path: path.clone(),
+            }
+        })?;
+
+        let options = config_file.into_options();
+
+        Ok(Self {
+            name: Name::new(system.current_directory().file_name().unwrap_or("root")),
+            root: system.current_directory().to_path_buf(),
+            options,
+            extra_configuration_paths: vec![path],
+        })
+    }
+
     /// Loads a project from a `pyproject.toml` file.
     pub(crate) fn from_pyproject(
         pyproject: PyProject,
@@ -106,11 +129,11 @@ impl ProjectMetadata {
     pub fn discover(
         path: &SystemPath,
         system: &dyn System,
-    ) -> Result<ProjectMetadata, ProjectDiscoveryError> {
+    ) -> Result<ProjectMetadata, ProjectMetadataError> {
         tracing::debug!("Searching for a project in '{path}'");
 
         if !system.is_directory(path) {
-            return Err(ProjectDiscoveryError::NotADirectory(path.to_path_buf()));
+            return Err(ProjectMetadataError::NotADirectory(path.to_path_buf()));
         }
 
         let mut closest_project: Option<ProjectMetadata> = None;
@@ -125,7 +148,7 @@ impl ProjectMetadata {
                 ) {
                     Ok(pyproject) => Some(pyproject),
                     Err(error) => {
-                        return Err(ProjectDiscoveryError::InvalidPyProject {
+                        return Err(ProjectMetadataError::InvalidPyProject {
                             path: pyproject_path,
                             source: Box::new(error),
                         });
@@ -144,7 +167,7 @@ impl ProjectMetadata {
                 ) {
                     Ok(options) => options,
                     Err(error) => {
-                        return Err(ProjectDiscoveryError::InvalidTyToml {
+                        return Err(ProjectMetadataError::InvalidTyToml {
                             path: ty_toml_path,
                             source: Box::new(error),
                         });
@@ -171,7 +194,7 @@ impl ProjectMetadata {
                         .and_then(|pyproject| pyproject.project.as_ref()),
                 )
                 .map_err(|err| {
-                    ProjectDiscoveryError::InvalidRequiresPythonConstraint {
+                    ProjectMetadataError::InvalidRequiresPythonConstraint {
                         source: err,
                         path: pyproject_path,
                     }
@@ -185,7 +208,7 @@ impl ProjectMetadata {
                 let metadata =
                     ProjectMetadata::from_pyproject(pyproject, project_root.to_path_buf())
                         .map_err(
-                            |err| ProjectDiscoveryError::InvalidRequiresPythonConstraint {
+                            |err| ProjectMetadataError::InvalidRequiresPythonConstraint {
                                 source: err,
                                 path: pyproject_path,
                             },
@@ -249,7 +272,7 @@ impl ProjectMetadata {
     }
 
     /// Combine the project options with the CLI options where the CLI options take precedence.
-    pub fn apply_cli_options(&mut self, options: Options) {
+    pub fn apply_options(&mut self, options: Options) {
         self.options = options.combine(std::mem::take(&mut self.options));
     }
 
@@ -282,7 +305,7 @@ impl ProjectMetadata {
 }
 
 #[derive(Debug, Error)]
-pub enum ProjectDiscoveryError {
+pub enum ProjectMetadataError {
     #[error("project path '{0}' is not a directory")]
     NotADirectory(SystemPathBuf),
 
@@ -303,6 +326,12 @@ pub enum ProjectDiscoveryError {
         source: ResolveRequiresPythonError,
         path: SystemPathBuf,
     },
+
+    #[error("Error loading configuration file at {path}: {source}")]
+    ConfigurationFileError {
+        source: Box<ConfigurationFileError>,
+        path: SystemPathBuf,
+    },
 }
 
 #[cfg(test)]
@@ -314,7 +343,7 @@ mod tests {
     use ruff_db::system::{SystemPathBuf, TestSystem};
     use ruff_python_ast::PythonVersion;
 
-    use crate::{ProjectDiscoveryError, ProjectMetadata};
+    use crate::{ProjectMetadata, ProjectMetadataError};
 
     #[test]
     fn project_without_pyproject() -> anyhow::Result<()> {
@@ -1076,7 +1105,7 @@ expected `.`, `]`
     }
 
     #[track_caller]
-    fn assert_error_eq(error: &ProjectDiscoveryError, message: &str) {
+    fn assert_error_eq(error: &ProjectMetadataError, message: &str) {
         assert_eq!(error.to_string().replace('\\', "/"), message);
     }
 

crates/ty_project/src/metadata/configuration_file.rs

@@ -14,6 +14,25 @@ pub(crate) struct ConfigurationFile {
 }
 
 impl ConfigurationFile {
+    pub(crate) fn from_path(
+        path: SystemPathBuf,
+        system: &dyn System,
+    ) -> Result<Self, ConfigurationFileError> {
+        let ty_toml_str = system.read_to_string(&path).map_err(|source| {
+            ConfigurationFileError::FileReadError {
+                source,
+                path: path.clone(),
+            }
+        })?;
+
+        match Options::from_toml_str(&ty_toml_str, ValueSource::File(Arc::new(path.clone()))) {
+            Ok(options) => Ok(Self { path, options }),
+            Err(error) => Err(ConfigurationFileError::InvalidTyToml {
+                source: Box::new(error),
+                path,
+            }),
+        }
+    }
     /// 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
@@ -66,4 +85,10 @@ pub enum ConfigurationFileError {
         source: Box<TyTomlError>,
         path: SystemPathBuf,
     },
+    #[error("Failed to read `{path}`: {source}")]
+    FileReadError {
+        #[source]
+        source: std::io::Error,
+        path: SystemPathBuf,
+    },
 }

crates/ty_project/src/metadata/options.rs

@@ -2,7 +2,7 @@ use crate::Db;
 use crate::metadata::value::{RangedValue, RelativePathBuf, ValueSource, ValueSourceGuard};
 use ruff_db::diagnostic::{Annotation, Diagnostic, DiagnosticFormat, DiagnosticId, Severity, Span};
 use ruff_db::files::system_path_to_file;
-use ruff_db::system::{System, SystemPath};
+use ruff_db::system::{System, SystemPath, SystemPathBuf};
 use ruff_macros::{Combine, OptionsMetadata};
 use ruff_python_ast::PythonVersion;
 use rustc_hash::FxHashMap;
@@ -575,3 +575,20 @@ impl OptionDiagnostic {
         }
     }
 }
+
+/// This is a wrapper for options that actually get loaded from configuration files
+/// and the CLI, which also includes a `config_file_override` option that overrides
+/// default configuration discovery with an explicitly-provided path to a configuration file
+pub struct ProjectOptionsOverrides {
+    pub config_file_override: Option<SystemPathBuf>,
+    pub options: Options,
+}
+
+impl ProjectOptionsOverrides {
+    pub fn new(config_file_override: Option<SystemPathBuf>, options: Options) -> Self {
+        Self {
+            config_file_override,
+            options,
+        }
+    }
+}