feat: add tsconfig discovery (#758)

Boshen · Boshen · commit 0e1674a29522 · 2025-10-17T10:40:26.000Z
## Summary Add automatic tsconfig.json discovery that traverses up parent directories, similar to how package.json is discovered. closes #626 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com> Rolldown PR: rolldown/rolldown#6602 Oxlint PR: oxc-project/oxc#14721
diff --git a/examples/resolver.rs b/examples/resolver.rs
@@ -2,7 +2,9 @@
 
 use std::path::PathBuf;
 
-use oxc_resolver::{AliasValue, ResolveOptions, Resolver, TsconfigOptions, TsconfigReferences};
+use oxc_resolver::{
+    AliasValue, ResolveOptions, Resolver, TsconfigDiscovery, TsconfigOptions, TsconfigReferences,
+};
 use pico_args::Arguments;
 
 fn main() {
@@ -30,10 +32,15 @@ fn main() {
         condition_names: vec!["node".into(), "import".into()],
         // CJS
         // condition_names: vec!["node".into(), "require".into()],
-        tsconfig: tsconfig_path.map(|config_file| TsconfigOptions {
-            config_file,
-            references: TsconfigReferences::Auto,
-        }),
+        tsconfig: Some(tsconfig_path.map_or_else(
+            || TsconfigDiscovery::Auto,
+            |config_file| {
+                TsconfigDiscovery::Manual(TsconfigOptions {
+                    config_file,
+                    references: TsconfigReferences::Auto,
+                })
+            },
+        )),
         ..ResolveOptions::default()
     };
 
@@ -45,7 +52,7 @@ fn main() {
             println!("Resolution: {}", resolution.full_path().to_string_lossy());
             println!("Module Type: {:?}", resolution.module_type());
             println!(
-                "package json: {:?}",
+                "package.json: {:?}",
                 resolution.package_json().map(|p| p.path.to_string_lossy())
             );
         }
diff --git a/napi/index.d.ts b/napi/index.d.ts
@@ -52,11 +52,11 @@ export declare const enum ModuleType {
  */
 export interface NapiResolveOptions {
   /**
-   * Path to TypeScript configuration file.
+   * Discover tsconfig automatically or use the specified tsconfig.json path.
    *
    * Default `None`
    */
-  tsconfig?: TsconfigOptions
+  tsconfig?: 'auto' | TsconfigOptions
   /**
    * Alias for [ResolveOptions::alias] and [ResolveOptions::fallback].
    *
diff --git a/napi/src/lib.rs b/napi/src/lib.rs
@@ -10,9 +10,9 @@ use std::{
     sync::Arc,
 };
 
-use napi::{Task, bindgen_prelude::AsyncTask};
+use napi::{Either, Task, bindgen_prelude::AsyncTask};
 use napi_derive::napi;
-use oxc_resolver::{ResolveError, ResolveOptions, Resolver};
+use oxc_resolver::{ResolveError, ResolveOptions, Resolver, TsconfigDiscovery, TsconfigOptions};
 
 use self::options::{NapiResolveOptions, StrOrStrList};
 
@@ -190,7 +190,10 @@ impl ResolverFactory {
         // merging options
         ResolveOptions {
             cwd: None,
-            tsconfig: op.tsconfig.map(|tsconfig| tsconfig.into()),
+            tsconfig: op.tsconfig.map(|value| match value {
+                Either::A(_) => TsconfigDiscovery::Auto,
+                Either::B(options) => TsconfigDiscovery::Manual(TsconfigOptions::from(options)),
+            }),
             alias: op
                 .alias
                 .map(|alias| {
diff --git a/napi/src/options.rs b/napi/src/options.rs
@@ -12,10 +12,11 @@ use napi_derive::napi;
 #[derive(Debug, Clone)]
 #[napi(object)]
 pub struct NapiResolveOptions {
-    /// Path to TypeScript configuration file.
+    /// Discover tsconfig automatically or use the specified tsconfig.json path.
     ///
     /// Default `None`
-    pub tsconfig: Option<TsconfigOptions>,
+    #[napi(ts_type = "'auto' | TsconfigOptions")]
+    pub tsconfig: Option<Either<String, TsconfigOptions>>,
 
     /// Alias for [ResolveOptions::alias] and [ResolveOptions::fallback].
     ///
diff --git a/src/cache/cached_path.rs b/src/cache/cached_path.rs
@@ -13,7 +13,7 @@ use once_cell::sync::OnceCell as OnceLock;
 use super::cache_impl::Cache;
 use super::thread_local::SCRATCH_PATH;
 use crate::{
-    FileMetadata, FileSystem, PackageJson, ResolveError, ResolveOptions,
+    FileMetadata, FileSystem, PackageJson, ResolveError, ResolveOptions, TsConfig,
     context::ResolveContext as Ctx,
 };
 
@@ -31,6 +31,7 @@ pub struct CachedPathImpl {
     pub canonicalizing: AtomicU64,
     pub node_modules: OnceLock<Option<Weak<CachedPathImpl>>>,
     pub package_json: OnceLock<Option<Arc<PackageJson>>>,
+    pub tsconfig: OnceLock<Option<Arc<TsConfig>>>,
 }
 
 impl CachedPathImpl {
@@ -52,6 +53,7 @@ impl CachedPathImpl {
             canonicalizing: AtomicU64::new(0),
             node_modules: OnceLock::new(),
             package_json: OnceLock::new(),
+            tsconfig: OnceLock::new(),
         }
     }
 }
diff --git a/src/lib.rs b/src/lib.rs
@@ -70,8 +70,8 @@ pub use crate::{
     error::{JSONError, ResolveError, SpecifierError},
     file_system::{FileMetadata, FileSystem, FileSystemOs},
     options::{
-        Alias, AliasValue, EnforceExtension, ResolveOptions, Restriction, TsconfigOptions,
-        TsconfigReferences,
+        Alias, AliasValue, EnforceExtension, ResolveOptions, Restriction, TsconfigDiscovery,
+        TsconfigOptions, TsconfigReferences,
     },
     package_json::{
         ImportsExportsArray, ImportsExportsEntry, ImportsExportsKind, ImportsExportsMap,
@@ -281,6 +281,7 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
             debug_assert!(path.starts_with(package_json.directory()));
         }
         let module_type = self.esm_file_format(&cached_path, ctx)?;
+
         Ok(Resolution {
             path,
             query: ctx.query.take(),
@@ -1456,21 +1457,78 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
         if cached_path.inside_node_modules() {
             return Ok(None);
         }
-        let Some(tsconfig_options) = &self.options.tsconfig else {
-            return Ok(None);
+        let tsconfig = match &self.options.tsconfig {
+            None => return Ok(None),
+            Some(TsconfigDiscovery::Manual(tsconfig_options)) => {
+                let tsconfig = self.load_tsconfig(
+                    /* root */ true,
+                    &tsconfig_options.config_file,
+                    &tsconfig_options.references,
+                    &mut TsconfigResolveContext::default(),
+                )?;
+                // Cache the loaded tsconfig in the path's directory
+                let tsconfig_dir = self.cache.value(tsconfig.directory());
+                _ = tsconfig_dir.tsconfig.get_or_init(|| Some(Arc::clone(&tsconfig)));
+                tsconfig
+            }
+            Some(TsconfigDiscovery::Auto) => {
+                let Some(tsconfig) = self.find_tsconfig(cached_path, ctx)? else {
+                    return Ok(None);
+                };
+                tsconfig
+            }
         };
-        let tsconfig = self.load_tsconfig(
-            /* root */ true,
-            &tsconfig_options.config_file,
-            &tsconfig_options.references,
-            &mut TsconfigResolveContext::default(),
-        )?;
+
         let paths = tsconfig.resolve(cached_path.path(), specifier);
         for path in paths {
-            let cached_path = self.cache.value(&path);
-            if let Some(path) = self.load_as_file_or_directory(&cached_path, ".", ctx)? {
-                return Ok(Some(path));
+            let resolved_path = self.cache.value(&path);
+            if let Some(resolution) = self.load_as_file_or_directory(&resolved_path, ".", ctx)? {
+                // Cache the tsconfig in the resolved path
+                _ = resolved_path.tsconfig.get_or_init(|| Some(Arc::clone(&tsconfig)));
+                return Ok(Some(resolution));
+            }
+        }
+        Ok(None)
+    }
+
+    /// Find tsconfig.json of a path by traversing parent directories.
+    ///
+    /// # Errors
+    ///
+    /// * [ResolveError::Json]
+    pub(crate) fn find_tsconfig(
+        &self,
+        cached_path: &CachedPath,
+        ctx: &mut Ctx,
+    ) -> Result<Option<Arc<TsConfig>>, ResolveError> {
+        // Don't discover tsconfig for paths inside node_modules
+        if cached_path.inside_node_modules() {
+            return Ok(None);
+        }
+
+        let mut cache_value = cached_path.clone();
+        // Go up directories when the querying path is not a directory
+        while !self.cache.is_dir(&cache_value, ctx) {
+            if let Some(cv) = cache_value.parent() {
+                cache_value = cv;
+            } else {
+                break;
+            }
+        }
+        let mut cache_value = Some(cache_value);
+        while let Some(cv) = cache_value {
+            if let Some(tsconfig) = cv.tsconfig.get_or_try_init(|| {
+                let tsconfig_path = cv.path.join("tsconfig.json");
+                let tsconfig_path = self.cache.value(&tsconfig_path);
+                if self.cache.is_file(&tsconfig_path, ctx) {
+                    self.resolve_tsconfig(tsconfig_path.path()).map(Some)
+                } else {
+                    Ok(None)
+                }
+            })? {
+                return Ok(Some(Arc::clone(tsconfig)));
             }
+            cache_value = cv.parent();
         }
         Ok(None)
     }
@@ -1487,6 +1545,7 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
             Some(b'.') => Ok(tsconfig.directory().normalize_with(specifier)),
             _ => self
                 .clone_with_options(ResolveOptions {
+                    tsconfig: None,
                     extensions: vec![".json".into()],
                     main_files: vec!["tsconfig.json".into()],
                     #[cfg(feature = "yarn_pnp")]
diff --git a/src/options.rs b/src/options.rs
@@ -15,10 +15,10 @@ pub struct ResolveOptions {
     /// Current working directory, used for testing purposes.
     pub cwd: Option<PathBuf>,
 
-    /// Path to TypeScript configuration file.
+    /// Discover tsconfig automatically or use the specified tsconfig.json path.
     ///
     /// Default `None`
-    pub tsconfig: Option<TsconfigOptions>,
+    pub tsconfig: Option<TsconfigDiscovery>,
 
     /// Create aliases to import or require certain modules more easily.
     ///
@@ -472,6 +472,12 @@ impl std::fmt::Debug for Restriction {
     }
 }
 
+#[derive(Debug, Clone)]
+pub enum TsconfigDiscovery {
+    Auto,
+    Manual(TsconfigOptions),
+}
+
 /// Tsconfig Options for [ResolveOptions::tsconfig]
 ///
 /// Derived from [tsconfig-paths-webpack-plugin](https://github.com/dividab/tsconfig-paths-webpack-plugin#options)
@@ -612,8 +618,8 @@ mod test {
     use std::path::PathBuf;
 
     use super::{
-        AliasValue, EnforceExtension, ResolveOptions, Restriction, TsconfigOptions,
-        TsconfigReferences,
+        AliasValue, EnforceExtension, ResolveOptions, Restriction, TsconfigDiscovery,
+        TsconfigOptions, TsconfigReferences,
     };
 
     #[test]
@@ -634,10 +640,10 @@ mod test {
     #[test]
     fn display() {
         let options = ResolveOptions {
-            tsconfig: Some(TsconfigOptions {
+            tsconfig: Some(TsconfigDiscovery::Manual(TsconfigOptions {
                 config_file: PathBuf::from("tsconfig.json"),
                 references: TsconfigReferences::Auto,
-            }),
+            })),
             alias: vec![("a".into(), vec![AliasValue::Ignore])],
             alias_fields: vec![vec!["browser".into()]],
             condition_names: vec!["require".into()],
@@ -657,7 +663,7 @@ mod test {
             ..ResolveOptions::default()
         };
 
-        let expected = r#"tsconfig:TsconfigOptions { config_file: "tsconfig.json", references: Auto },alias:[("a", [Ignore])],alias_fields:[["browser"]],condition_names:["require"],enforce_extension:Enabled,exports_fields:[["exports"]],imports_fields:[["imports"]],extension_alias:[(".js", [".ts"])],extensions:[".js", ".json", ".node"],fallback:[("fallback", [Ignore])],fully_specified:true,main_fields:["main"],main_files:["index"],modules:["node_modules"],resolve_to_context:true,prefer_relative:true,prefer_absolute:true,restrictions:[Path("restrictions")],roots:["roots"],symlinks:true,builtin_modules:true,allow_package_exports_in_directory_resolve:true,"#;
+        let expected = r#"tsconfig:Manual(TsconfigOptions { config_file: "tsconfig.json", references: Auto }),alias:[("a", [Ignore])],alias_fields:[["browser"]],condition_names:["require"],enforce_extension:Enabled,exports_fields:[["exports"]],imports_fields:[["imports"]],extension_alias:[(".js", [".ts"])],extensions:[".js", ".json", ".node"],fallback:[("fallback", [Ignore])],fully_specified:true,main_fields:["main"],main_files:["index"],modules:["node_modules"],resolve_to_context:true,prefer_relative:true,prefer_absolute:true,restrictions:[Path("restrictions")],roots:["roots"],symlinks:true,builtin_modules:true,allow_package_exports_in_directory_resolve:true,"#;
         assert_eq!(format!("{options}"), expected);
 
         let options = ResolveOptions {
diff --git a/src/tests/mod.rs b/src/tests/mod.rs
@@ -24,6 +24,7 @@ mod roots;
 mod scoped_packages;
 mod simple;
 mod symlink;
+mod tsconfig_discovery;
 mod tsconfig_extends;
 mod tsconfig_paths;
 mod tsconfig_project_references;
diff --git a/src/tests/tsconfig_discovery.rs b/src/tests/tsconfig_discovery.rs
@@ -0,0 +1,8 @@
+//! Tests for tsconfig discovery
+//!
+//! Tests that tsconfig.json can be auto-discovered when no explicit tsconfig option is provided.
+
+#[test]
+fn tsconfig_discovery() {
+    super::tsconfig_paths::tsconfig_resolve_impl(/* tsconfig_discovery */ true);
+}
diff --git a/src/tests/tsconfig_extends.rs b/src/tests/tsconfig_extends.rs
diff --git a/src/tests/tsconfig_paths.rs b/src/tests/tsconfig_paths.rs
diff --git a/src/tests/tsconfig_project_references.rs b/src/tests/tsconfig_project_references.rs

Original file line number	Diff line number	Diff line change
`@@ -52,11 +52,11 @@ export declare const enum ModuleType {`
`52`	`52`	`*/`
`53`	`53`	`export interface NapiResolveOptions {`
`54`	`54`	`/**`
`55`		`- * Path to TypeScript configuration file.`
	`55`	`+ * Discover tsconfig automatically or use the specified tsconfig.json path.`
`56`	`56`	`*`
`57`	`57`	* Default `None`
`58`	`58`	`*/`
`59`		`- tsconfig?: TsconfigOptions`
	`59`	`+ tsconfig?: 'auto' \| TsconfigOptions`
`60`	`60`	`/**`
`61`	`61`	`* Alias for [ResolveOptions::alias] and [ResolveOptions::fallback].`
`62`	`62`	`*`
Original file line number	Diff line number	Diff line change
`@@ -13,7 +13,7 @@ use once_cell::sync::OnceCell as OnceLock;`
`13`	`13`	`use super::cache_impl::Cache;`
`14`	`14`	`use super::thread_local::SCRATCH_PATH;`
`15`	`15`	`use crate::{`
`16`		`- FileMetadata, FileSystem, PackageJson, ResolveError, ResolveOptions,`
	`16`	`+ FileMetadata, FileSystem, PackageJson, ResolveError, ResolveOptions, TsConfig,`
`17`	`17`	`context::ResolveContext as Ctx,`
`18`	`18`	`};`
`19`	`19`
`@@ -31,6 +31,7 @@ pub struct CachedPathImpl {`
`31`	`31`	`pub canonicalizing: AtomicU64,`
`32`	`32`	`pub node_modules: OnceLock<Option<Weak<CachedPathImpl>>>,`
`33`	`33`	`pub package_json: OnceLock<Option<Arc<PackageJson>>>,`
	`34`	`+ pub tsconfig: OnceLock<Option<Arc<TsConfig>>>,`
`34`	`35`	`}`
`35`	`36`
`36`	`37`	`impl CachedPathImpl {`
`@@ -52,6 +53,7 @@ impl CachedPathImpl {`
`52`	`53`	`canonicalizing: AtomicU64::new(0),`
`53`	`54`	`node_modules: OnceLock::new(),`
`54`	`55`	`package_json: OnceLock::new(),`
	`56`	`+ tsconfig: OnceLock::new(),`
`55`	`57`	`}`
`56`	`58`	`}`
`57`	`59`	`}`