feat(tsconfig): implement solution-style tsconfig resolution

Cargo.toml

@@ -78,6 +78,7 @@ name = "resolver"
 
 [dependencies]
 cfg-if = "1"
+fast-glob = "1.0.0"
 indexmap = { version = "2", features = ["serde"] }
 json-strip-comments = "3"
 once_cell = "1" # Use `std::sync::OnceLock::get_or_try_init` when it is stable.

fixtures/tsconfig/cases/solution_style/packages/pkg-a/src/index.ts

@@ -0,0 +1 @@
+export const pkgAIndex = 'pkg-a';

fixtures/tsconfig/cases/solution_style/packages/pkg-a/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "baseUrl": ".",
+    "paths": {
+      "@pkg-a/*": ["./src/*"]
+    }
+  },
+  "include": ["src/**/*"]
+}

fixtures/tsconfig/cases/solution_style/packages/pkg-b/src/index.js

@@ -0,0 +1 @@
+export const pkgBIndexJS = 'pkg-b-js';

fixtures/tsconfig/cases/solution_style/packages/pkg-b/src/index.ts

@@ -0,0 +1 @@
+export const pkgBIndex = 'pkg-b';

fixtures/tsconfig/cases/solution_style/packages/pkg-b/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "baseUrl": ".",
+    "allowJs": true,
+    "paths": {
+      "@pkg-b/*": ["./src/*"]
+    }
+  },
+  "include": ["src/**/*"]
+}

fixtures/tsconfig/cases/solution_style/packages/pkg-c/lib/index.test.ts

@@ -0,0 +1 @@
+// This file should be excluded by pkg-c's exclude pattern

fixtures/tsconfig/cases/solution_style/packages/pkg-c/lib/index.ts

@@ -0,0 +1 @@
+export const pkgCIndex = 'pkg-c';

fixtures/tsconfig/cases/solution_style/packages/pkg-c/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "baseUrl": ".",
+    "paths": {
+      "@pkg-c/*": ["./lib/*"]
+    }
+  },
+  "include": ["lib/**/*"],
+  "exclude": ["lib/**/*.test.ts"]
+}

fixtures/tsconfig/cases/solution_style/src/index.ts

@@ -0,0 +1 @@
+export const rootIndex = 'root';

fixtures/tsconfig/cases/solution_style/tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "baseUrl": ".",
+    "allowJs": true,
+    "paths": {
+      "root/*": ["./src/*"]
+    }
+  },
+  "include": ["src/**/*"],
+  "references": [
+    { "path": "./packages/pkg-a" },
+    { "path": "./packages/pkg-b" },
+    { "path": "./packages/pkg-c" }
+  ]
+}

src/lib.rs

@@ -199,13 +199,16 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
     ///
     /// * See [ResolveError]
     pub fn resolve_tsconfig<P: AsRef<Path>>(&self, path: P) -> Result<Arc<TsConfig>, ResolveError> {
+        self.resolve_tsconfig_with_references(path, &TsconfigReferences::Auto)
+    }
+
+    pub fn resolve_tsconfig_with_references<P: AsRef<Path>>(
+        &self,
+        path: P,
+        references: &TsconfigReferences,
+    ) -> Result<Arc<TsConfig>, ResolveError> {
         let path = path.as_ref();
-        self.load_tsconfig(
-            true,
-            path,
-            &TsconfigReferences::Auto,
-            &mut TsconfigResolveContext::default(),
-        )
+        self.load_tsconfig(true, path, references, &mut TsconfigResolveContext::default())
     }
 
     /// Resolve `specifier` at absolute `path` with [ResolveContext]
@@ -1469,7 +1472,7 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
                 let Some(tsconfig) = self.find_tsconfig(cached_path, ctx)? else {
                     return Ok(None);
                 };
-                tsconfig
+                tsconfig.resolve_for_file(cached_path.path())
             }
         };
 

src/tests/mod.rs

@@ -28,6 +28,7 @@ mod tsconfig_discovery;
 mod tsconfig_extends;
 mod tsconfig_paths;
 mod tsconfig_project_references;
+mod tsconfig_solution_style;
 #[cfg(target_os = "windows")]
 mod windows;
 

src/tests/tsconfig_solution_style.rs

@@ -0,0 +1,174 @@
+//! Tests for solution-style tsconfig resolution
+//!
+//! Tests the `TsConfig::resolve_for_file` method which implements solution-style
+//! tsconfig resolution similar to tsconfck's `resolveSolutionTSConfig`.
+
+use std::{path::Path, sync::Arc};
+
+use crate::{ResolveOptions, Resolver, TsConfig};
+
+/// Helper function to load a tsconfig with references
+fn load_tsconfig(path: &Path) -> Arc<TsConfig> {
+    let resolver = Resolver::new(ResolveOptions::default());
+    resolver.resolve_tsconfig(path).unwrap()
+}
+
+#[test]
+fn resolve_for_file_basic() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+
+    // Load root tsconfig with references
+    let root_tsconfig = load_tsconfig(&f.join("tsconfig.json"));
+
+    // File in root src/ should use root tsconfig
+    let file_path = f.join("src/index.ts");
+    let resolved = root_tsconfig.resolve_for_file(&file_path);
+    assert_eq!(resolved.path(), root_tsconfig.path(), "File in src/ should use root tsconfig");
+
+    // File in pkg-a should use pkg-a's tsconfig
+    let file_path = f.join("packages/pkg-a/src/index.ts");
+    let resolved = root_tsconfig.resolve_for_file(&file_path);
+    assert_eq!(
+        resolved.path(),
+        f.join("packages/pkg-a/tsconfig.json"),
+        "File in pkg-a/src/ should use pkg-a's tsconfig"
+    );
+
+    // File in pkg-b should use pkg-b's tsconfig
+    let file_path = f.join("packages/pkg-b/src/index.ts");
+    let resolved = root_tsconfig.resolve_for_file(&file_path);
+    assert_eq!(
+        resolved.path(),
+        f.join("packages/pkg-b/tsconfig.json"),
+        "File in pkg-b/src/ should use pkg-b's tsconfig"
+    );
+
+    // File in pkg-c's lib/ should use pkg-c's tsconfig
+    let file_path = f.join("packages/pkg-c/lib/index.ts");
+    let resolved = root_tsconfig.resolve_for_file(&file_path);
+    assert_eq!(
+        resolved.path(),
+        f.join("packages/pkg-c/tsconfig.json"),
+        "File in pkg-c/lib/ should use pkg-c's tsconfig"
+    );
+}
+
+#[test]
+fn resolve_for_file_exclude_patterns() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+    let root_tsconfig = load_tsconfig(&f.join("tsconfig.json"));
+
+    // pkg-c excludes *.test.ts files
+    let excluded_file = f.join("packages/pkg-c/lib/index.test.ts");
+    let resolved = root_tsconfig.resolve_for_file(&excluded_file);
+
+    // Should fall back to root tsconfig since file is excluded from pkg-c
+    assert_eq!(
+        resolved.path(),
+        root_tsconfig.path(),
+        "Excluded files should fall back to root tsconfig"
+    );
+
+    // Non-excluded file should still use pkg-c's tsconfig
+    let included_file = f.join("packages/pkg-c/lib/index.ts");
+    let resolved = root_tsconfig.resolve_for_file(&included_file);
+    assert_eq!(
+        resolved.path(),
+        f.join("packages/pkg-c/tsconfig.json"),
+        "Non-excluded files should use pkg-c's tsconfig"
+    );
+}
+
+#[test]
+fn resolve_for_file_allowjs() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+    let root_tsconfig = load_tsconfig(&f.join("tsconfig.json"));
+
+    // pkg-b has allowJs: true, so .js files should use pkg-b's tsconfig
+    let js_file = f.join("packages/pkg-b/src/index.js");
+    let resolved = root_tsconfig.resolve_for_file(&js_file);
+    assert_eq!(
+        resolved.path(),
+        f.join("packages/pkg-b/tsconfig.json"),
+        "With allowJs, .js files should use pkg-b's tsconfig"
+    );
+
+    // pkg-a doesn't have allowJs, so .js files should fall back to root
+    let js_file = f.join("packages/pkg-a/src/script.js");
+    let resolved = root_tsconfig.resolve_for_file(&js_file);
+    assert_eq!(
+        resolved.path(),
+        root_tsconfig.path(),
+        "Without allowJs, .js files should fall back to root tsconfig"
+    );
+}
+
+#[test]
+fn resolve_for_file_non_ts_js_files() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+    let root_tsconfig = load_tsconfig(&f.join("tsconfig.json"));
+
+    // Non-TS/JS files should not trigger solution-style resolution
+    let json_file = f.join("packages/pkg-a/src/data.json");
+    let resolved = root_tsconfig.resolve_for_file(&json_file);
+    assert_eq!(resolved.path(), root_tsconfig.path(), "Non-TS/JS files should use root tsconfig");
+
+    // .css, .html, etc. should also fall back to root
+    let css_file = f.join("packages/pkg-a/src/styles.css");
+    let resolved = root_tsconfig.resolve_for_file(&css_file);
+    assert_eq!(resolved.path(), root_tsconfig.path(), "CSS files should use root tsconfig");
+}
+
+#[test]
+fn resolve_for_file_no_references() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+
+    // Load pkg-a's tsconfig which has no references
+    let pkg_a_tsconfig = load_tsconfig(&f.join("packages/pkg-a/tsconfig.json"));
+
+    // When a tsconfig has no references, it should always return itself
+    let file_in_pkg_a = f.join("packages/pkg-a/src/index.ts");
+    let resolved = pkg_a_tsconfig.resolve_for_file(&file_in_pkg_a);
+    assert_eq!(
+        resolved.path(),
+        pkg_a_tsconfig.path(),
+        "Tsconfig without references should always return itself"
+    );
+
+    // Even for files outside its directory
+    let file_in_pkg_b = f.join("packages/pkg-b/src/index.ts");
+    let resolved = pkg_a_tsconfig.resolve_for_file(&file_in_pkg_b);
+    assert_eq!(
+        resolved.path(),
+        pkg_a_tsconfig.path(),
+        "Tsconfig without references should return itself for any file"
+    );
+}
+
+#[test]
+fn resolve_for_file_extensions() {
+    let f = super::fixture_root().join("tsconfig/cases/solution_style");
+    let root_tsconfig = load_tsconfig(&f.join("tsconfig.json"));
+
+    // Test all TS extensions
+    for ext in ["ts", "tsx", "mts", "cts"] {
+        let file = f.join(format!("packages/pkg-a/src/index.{ext}"));
+        let resolved = root_tsconfig.resolve_for_file(&file);
+        assert_eq!(
+            resolved.path(),
+            f.join("packages/pkg-a/tsconfig.json"),
+            ".{ext} files should trigger solution-style resolution"
+        );
+    }
+
+    // Test JS extensions with allowJs
+    for ext in ["js", "jsx", "mjs", "cjs"] {
+        let file = f.join(format!("packages/pkg-b/src/index.{ext}"));
+        let resolved = root_tsconfig.resolve_for_file(&file);
+        assert_eq!(
+            resolved.path(),
+            f.join("packages/pkg-b/tsconfig.json"),
+            ".{ext} files should trigger solution-style resolution with allowJs"
+        );
+    }
+}