[ty] Make the default database truly statically infallible

crates/ruff_benchmark/benches/ty.rs

@@ -92,7 +92,7 @@ fn setup_tomllib_case() -> Case {
         ..Options::default()
     });
 
-    let mut db = ProjectDatabase::new(metadata, system).unwrap();
+    let mut db = ProjectDatabase::fallible(metadata, system).unwrap();
     let mut tomllib_files = FxHashSet::default();
     let mut re: Option<File> = None;
 
@@ -239,7 +239,7 @@ fn setup_micro_case(code: &str) -> Case {
         ..Options::default()
     });
 
-    let mut db = ProjectDatabase::new(metadata, system).unwrap();
+    let mut db = ProjectDatabase::fallible(metadata, system).unwrap();
     let file = system_path_to_file(&db, SystemPathBuf::from(file_path)).unwrap();
 
     db.set_check_mode(CheckMode::OpenFiles);
@@ -812,7 +812,7 @@ impl<'a> ProjectBenchmark<'a> {
             ..Options::default()
         });
 
-        let mut db = ProjectDatabase::new(metadata, system).unwrap();
+        let mut db = ProjectDatabase::fallible(metadata, system).unwrap();
 
         db.project().set_included_paths(
             &mut db,

crates/ruff_benchmark/benches/ty_walltime.rs

@@ -51,7 +51,7 @@ impl<'a> Benchmark<'a> {
             ..Options::default()
         });
 
-        let mut db = ProjectDatabase::new(metadata, system).unwrap();
+        let mut db = ProjectDatabase::fallible(metadata, system).unwrap();
 
         db.project().set_included_paths(
             &mut db,

crates/ruff_graph/src/db.rs

@@ -7,7 +7,7 @@ use ruff_db::files::Files;
 use ruff_db::system::{OsSystem, System, SystemPathBuf};
 use ruff_db::vendored::{VendoredFileSystem, VendoredFileSystemBuilder};
 use ruff_python_ast::PythonVersion;
-use ty_module_resolver::{SearchPathSettings, SearchPaths};
+use ty_module_resolver::{FallibleStrategy, SearchPathSettings, SearchPaths};
 use ty_site_packages::{PythonEnvironment, SysPrefixPathOrigin};
 
 static EMPTY_VENDORED: std::sync::LazyLock<VendoredFileSystem> = std::sync::LazyLock::new(|| {
@@ -45,7 +45,7 @@ impl ModuleDb {
                 .into_vec();
         }
         let search_paths = search_path_settings
-            .to_search_paths(&system, &EMPTY_VENDORED)
+            .to_search_paths(&system, &EMPTY_VENDORED, &FallibleStrategy)
             .context("Invalid search path settings")?;
 
         let db = Self {

crates/ty/src/lib.rs

@@ -146,7 +146,7 @@ fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
     let project_options_overrides = ProjectOptionsOverrides::new(config_file, args.into_options());
     project_metadata.apply_overrides(&project_options_overrides);
 
-    let mut db = ProjectDatabase::new(project_metadata, system)?;
+    let mut db = ProjectDatabase::fallible(project_metadata, system)?;
     let project = db.project();
 
     project.set_verbose(&mut db, verbosity >= VerbosityLevel::Verbose);

crates/ty/tests/file_watching.rs

@@ -435,7 +435,7 @@ where
         }
     }
 
-    let mut db = ProjectDatabase::new(project, system)?;
+    let mut db = ProjectDatabase::fallible(project, system)?;
 
     if let Some(included_paths) = included_paths {
         db.project().set_included_paths(&mut db, included_paths);

crates/ty_completion_bench/src/main.rs

@@ -99,7 +99,7 @@ fn main() -> anyhow::Result<ExitCode> {
         ..Options::default()
     });
     project_metadata.apply_configuration_files(&system)?;
-    let db = ProjectDatabase::new(project_metadata, system)?;
+    let db = ProjectDatabase::fallible(project_metadata, system)?;
 
     let start = std::time::Instant::now();
     let mut completions = get_completions(&db, &args.file, offset)?;

crates/ty_completion_eval/src/main.rs

@@ -290,7 +290,7 @@ impl Task {
             ..Options::default()
         });
         project_metadata.apply_configuration_files(&system)?;
-        let db = ProjectDatabase::new(project_metadata, system)?;
+        let db = ProjectDatabase::fallible(project_metadata, system)?;
         Ok(Task {
             db,
             dir: project_path.to_path_buf(),

crates/ty_ide/src/lib.rs

@@ -562,7 +562,7 @@ mod tests {
     impl SitePackagesCursorTestBuilder {
         pub(super) fn build(&self) -> CursorTest {
             use ty_module_resolver::SearchPathSettings;
-            use ty_python_semantic::{Program, ProgramSettings};
+            use ty_python_semantic::{FallibleStrategy, Program, ProgramSettings};
 
             let project_root = SystemPathBuf::from("/src");
             let site_packages_path = SystemPathBuf::from("/site-packages");
@@ -593,7 +593,7 @@ mod tests {
                 site_packages_paths: vec![site_packages_path.clone()],
                 ..SearchPathSettings::empty()
             }
-            .to_search_paths(db.system(), db.vendored())
+            .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
             .expect("valid search paths");
 
             Program::from_settings(

crates/ty_module_resolver/Cargo.toml

@@ -16,6 +16,7 @@ ruff_memory_usage = { workspace = true }
 ruff_python_ast = { workspace = true, features = ["salsa"] }
 ruff_python_stdlib = { workspace = true }
 
+anyhow = { workspace = true }
 camino = { workspace = true }
 compact_str = { workspace = true }
 get-size2 = { workspace = true }

crates/ty_module_resolver/src/lib.rs

@@ -11,7 +11,8 @@ pub use resolve::{
     SearchPaths, file_to_module, resolve_module, resolve_module_confident, resolve_real_module,
     resolve_real_module_confident, resolve_real_shadowable_module,
 };
-pub use settings::{MisconfigurationMode, SearchPathSettings, SearchPathSettingsError};
+pub use settings::{SearchPathSettings, SearchPathSettingsError};
+pub use strategy::{FallibleStrategy, MisconfigurationStrategy, UseDefaultStrategy};
 pub use typeshed::{
     PyVersionRange, TypeshedVersions, TypeshedVersionsParseError, vendored_typeshed_versions,
 };
@@ -28,6 +29,7 @@ mod module_name;
 mod path;
 mod resolve;
 mod settings;
+mod strategy;
 mod typeshed;
 
 #[cfg(test)]

crates/ty_module_resolver/src/list.rs

@@ -387,6 +387,7 @@ mod tests {
         ModuleResolveMode, ModuleResolveModeIngredient, dynamic_resolution_paths,
     };
     use crate::settings::SearchPathSettings;
+    use crate::strategy::FallibleStrategy;
     use crate::testing::{FileSpec, MockedTypeshed, TestCase, TestCaseBuilder};
 
     use super::list_modules;
@@ -966,7 +967,7 @@ mod tests {
 
         db.set_search_paths(
             settings
-                .to_search_paths(db.system(), db.vendored())
+                .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
                 .expect("Valid search path settings"),
         );
 
@@ -1473,7 +1474,7 @@ not_a_directory
 
         db.set_search_paths(
             settings
-                .to_search_paths(db.system(), db.vendored())
+                .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
                 .expect("Valid search path settings"),
         );
 
@@ -1524,7 +1525,7 @@ not_a_directory
 
         db.set_search_paths(
             settings
-                .to_search_paths(db.system(), db.vendored())
+                .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
                 .expect("Valid search path settings"),
         );
 
@@ -1604,7 +1605,7 @@ not_a_directory
 
         let settings = SearchPathSettings::new(vec![src]);
         let search_paths = settings
-            .to_search_paths(db.system(), db.vendored())
+            .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
             .expect("valid search path settings");
         db.set_search_paths(search_paths);
 
@@ -1644,7 +1645,7 @@ not_a_directory
         };
         db.set_search_paths(
             settings
-                .to_search_paths(db.system(), db.vendored())
+                .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
                 .unwrap(),
         );
 
@@ -1792,7 +1793,7 @@ not_a_directory
 
         let settings = SearchPathSettings::new(vec![project_directory]);
         let search_paths = settings
-            .to_search_paths(db.system(), db.vendored())
+            .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
             .expect("Valid search path settings");
         db.set_search_paths(search_paths);
 

crates/ty_module_resolver/src/resolve.rs

@@ -51,8 +51,9 @@ use crate::db::Db;
 use crate::module::{Module, ModuleKind};
 use crate::module_name::ModuleName;
 use crate::path::{ModulePath, SearchPath, SystemOrVendoredPathRef};
+use crate::strategy::MisconfigurationStrategy;
 use crate::typeshed::{TypeshedVersions, vendored_typeshed_versions};
-use crate::{MisconfigurationMode, SearchPathSettings, SearchPathSettingsError};
+use crate::{SearchPathSettings, SearchPathSettingsError};
 
 /// Resolves a module name to a module.
 pub fn resolve_module<'db>(
@@ -552,11 +553,12 @@ impl SearchPaths {
     /// This method also implements the typing spec's [module resolution order].
     ///
     /// [module resolution order]: https://typing.python.org/en/latest/spec/distributing.html#import-resolution-ordering
-    pub fn from_settings(
+    pub fn from_settings<Strategy: MisconfigurationStrategy>(
         settings: &SearchPathSettings,
         system: &dyn System,
         vendored: &VendoredFileSystem,
-    ) -> Result<Self, SearchPathSettingsError> {
+        strategy: &Strategy,
+    ) -> Result<Self, Strategy::Error<SearchPathSettingsError>> {
         fn canonicalize(path: &SystemPath, system: &dyn System) -> SystemPathBuf {
             system
                 .canonicalize_path(path)
@@ -569,7 +571,6 @@ impl SearchPaths {
             custom_typeshed: typeshed,
             site_packages_paths,
             real_stdlib_path,
-            misconfiguration_mode,
         } = settings;
 
         let mut static_paths = vec![];
@@ -578,30 +579,25 @@ impl SearchPaths {
             let path = canonicalize(path, system);
             tracing::debug!("Adding extra search-path `{path}`");
 
-            match SearchPath::extra(system, path) {
-                Ok(path) => static_paths.push(path),
-                Err(err) => {
-                    if *misconfiguration_mode == MisconfigurationMode::UseDefault {
-                        tracing::debug!("Skipping invalid extra search-path: {err}");
-                    } else {
-                        return Err(err.into());
-                    }
-                }
-            }
+            let path = strategy.fallback_opt(
+                SearchPath::extra(system, path).map_err(SearchPathSettingsError::from),
+                |err| {
+                    tracing::debug!("Skipping invalid extra search-path: {err}");
+                },
+            )?;
+            static_paths.extend(path);
         }
 
         for src_root in src_roots {
             tracing::debug!("Adding first-party search path `{src_root}`");
-            match SearchPath::first_party(system, src_root.to_path_buf()) {
-                Ok(path) => static_paths.push(path),
-                Err(err) => {
-                    if *misconfiguration_mode == MisconfigurationMode::UseDefault {
-                        tracing::debug!("Skipping invalid first-party search-path: {err}");
-                    } else {
-                        return Err(err.into());
-                    }
-                }
-            }
+            let path = strategy.fallback_opt(
+                SearchPath::first_party(system, src_root.to_path_buf())
+                    .map_err(SearchPathSettingsError::from),
+                |err| {
+                    tracing::debug!("Skipping invalid first-party search-path: {err}");
+                },
+            )?;
+            static_paths.extend(path);
         }
 
         let (typeshed_versions, stdlib_path) = if let Some(typeshed) = typeshed {
@@ -619,20 +615,13 @@ impl SearchPaths {
                 .and_then(|versions_content| Ok(versions_content.parse()?))
                 .and_then(|parsed| Ok((parsed, SearchPath::custom_stdlib(system, &typeshed)?)));
 
-            match results {
-                Ok(results) => results,
-                Err(err) => {
-                    if settings.misconfiguration_mode == MisconfigurationMode::UseDefault {
-                        tracing::debug!("Skipping custom-stdlib search-path: {err}");
-                        (
-                            vendored_typeshed_versions(vendored),
-                            SearchPath::vendored_stdlib(),
-                        )
-                    } else {
-                        return Err(err);
-                    }
-                }
-            }
+            strategy.fallback(results, |err| {
+                tracing::debug!("Skipping custom-stdlib search-path: {err}");
+                (
+                    vendored_typeshed_versions(vendored),
+                    SearchPath::vendored_stdlib(),
+                )
+            })?
         } else {
             tracing::debug!("Using vendored stdlib");
             (
@@ -642,17 +631,13 @@ impl SearchPaths {
         };
 
         let real_stdlib_path = if let Some(path) = real_stdlib_path {
-            match SearchPath::real_stdlib(system, path.clone()) {
-                Ok(path) => Some(path),
-                Err(err) => {
-                    if *misconfiguration_mode == MisconfigurationMode::UseDefault {
-                        tracing::debug!("Skipping invalid real-stdlib search-path: {err}");
-                        None
-                    } else {
-                        return Err(err.into());
-                    }
-                }
-            }
+            strategy.fallback_opt(
+                SearchPath::real_stdlib(system, path.clone())
+                    .map_err(SearchPathSettingsError::from),
+                |err| {
+                    tracing::debug!("Skipping invalid real-stdlib search-path: {err}");
+                },
+            )?
         } else {
             None
         };
@@ -661,16 +646,14 @@ impl SearchPaths {
 
         for path in site_packages_paths {
             tracing::debug!("Adding site-packages search path `{path}`");
-            match SearchPath::site_packages(system, path.clone()) {
-                Ok(path) => site_packages.push(path),
-                Err(err) => {
-                    if settings.misconfiguration_mode == MisconfigurationMode::UseDefault {
-                        tracing::debug!("Skipping invalid site-packages search-path: {err}");
-                    } else {
-                        return Err(err.into());
-                    }
-                }
-            }
+            let path = strategy.fallback_opt(
+                SearchPath::site_packages(system, path.clone())
+                    .map_err(SearchPathSettingsError::from),
+                |err| {
+                    tracing::debug!("Skipping invalid site-packages search-path: {err}");
+                },
+            )?;
+            site_packages.extend(path);
         }
 
         // TODO vendor typeshed's third-party stubs as well as the stdlib and
@@ -1827,6 +1810,7 @@ mod tests {
     use crate::db::tests::TestDb;
     use crate::module::ModuleKind;
     use crate::module_name::ModuleName;
+    use crate::strategy::FallibleStrategy;
     use crate::testing::{FileSpec, MockedTypeshed, TestCase, TestCaseBuilder};
 
     use super::*;
@@ -2387,7 +2371,7 @@ mod tests {
                 site_packages_paths: vec![site_packages],
                 ..SearchPathSettings::empty()
             }
-            .to_search_paths(db.system(), db.vendored())
+            .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
             .expect("Valid search path settings"),
         );
 
@@ -2926,7 +2910,7 @@ not_a_directory
                 site_packages_paths: vec![venv_site_packages, system_site_packages],
                 ..SearchPathSettings::new(vec![SystemPathBuf::from("/src")])
             }
-            .to_search_paths(db.system(), db.vendored())
+            .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
             .expect("Valid search path settings"),
         );
 
@@ -2994,7 +2978,7 @@ not_a_directory
 
         db.set_search_paths(
             SearchPathSettings::new(vec![src])
-                .to_search_paths(db.system(), db.vendored())
+                .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
                 .expect("Valid search path settings"),
         );
 
@@ -3032,7 +3016,7 @@ not_a_directory
             site_packages_paths: vec![site_packages.clone()],
             ..SearchPathSettings::empty()
         }
-        .to_search_paths(db.system(), db.vendored())
+        .to_search_paths(db.system(), db.vendored(), &FallibleStrategy)
         .expect("Valid search path settings");
         db.set_search_paths(search_paths);