fix(oxlint): Skip vite.config.ts w/o .lint field in auto-discovery

apps/oxlint/src/config_loader.rs

@@ -14,6 +14,7 @@ use rustc_hash::{FxBuildHasher, FxHashMap, FxHashSet};
 
 use crate::{
     DEFAULT_JSONC_OXLINTRC_NAME, DEFAULT_OXLINTRC_NAME, DEFAULT_TS_OXLINTRC_NAME, VITE_CONFIG_NAME,
+    VITE_OXLINT_CONFIG_FIELD,
 };
 
 #[cfg(feature = "napi")]
@@ -490,9 +491,12 @@ impl<'a> ConfigLoader<'a> {
         }
 
         // Fallback: check for vite.config.ts with .lint field (lowest priority)
-        let vite_path = dir.join(VITE_CONFIG_NAME);
-        if vite_path.is_file() {
-            return self.load_root_js_config(&vite_path).map(Some);
+        // If .lint field is missing, skip it and continue config search.
+        let vite_config_path = dir.join(VITE_CONFIG_NAME);
+        if vite_config_path.is_file()
+            && let Some(config) = self.try_load_root_vite_config(&vite_config_path)?
+        {
+            return Ok(Some(config));
         }
 
         Ok(None)
@@ -556,6 +560,28 @@ impl<'a> ConfigLoader<'a> {
         Ok(Oxlintrc::default())
     }
 
+    /// Try to load vite.config.ts, returning `Ok(None)` if `.lint` field is missing.
+    /// Other errors (e.g., JS runtime not available, parse errors) are propagated.
+    fn try_load_root_vite_config(&self, path: &Path) -> Result<Option<Oxlintrc>, OxcDiagnostic> {
+        match self.load_root_js_config(path) {
+            Ok(config) => Ok(Some(config)),
+            Err(diagnostic) => {
+                let msg = diagnostic.message.to_string();
+                // NOTE: This relies on matching the error message from `parse_js_config_response` in js_config.rs.
+                // If that message changes, this match must be updated accordingly.
+                if msg.contains(&format!("Expected a `{VITE_OXLINT_CONFIG_FIELD}` field")) {
+                    tracing::debug!(
+                        "Skipping {} (no `{VITE_OXLINT_CONFIG_FIELD}` field), continuing config search...",
+                        path.display(),
+                    );
+                    Ok(None)
+                } else {
+                    Err(diagnostic)
+                }
+            }
+        }
+    }
+
     fn load_root_js_config(&self, path: &Path) -> Result<Oxlintrc, OxcDiagnostic> {
         match self.load_js_configs(&[path.to_path_buf()]) {
             Ok(mut configs) => Ok(configs.pop().unwrap_or_default()),

apps/oxlint/src/js_config.rs

@@ -129,6 +129,8 @@ fn parse_js_config_response(json: &str) -> Result<Vec<JsConfigResult>, Vec<OxcDi
                         if let Some(v) = entry.config.get(VITE_OXLINT_CONFIG_FIELD).cloned() {
                             v
                         } else {
+                            // NOTE: This error message is shown to users (explicit `--config`) and also
+                            // matched by `try_load_root_vite_config` in config_loader.rs (auto-discovery skip).
                             errors.push(OxcDiagnostic::error(format!(
                                 "Expected a `{VITE_OXLINT_CONFIG_FIELD}` field in the default export of {}",
                                 entry.path

apps/oxlint/test/fixtures/vite_config_explicit_no_lint_field/files/test.js

@@ -0,0 +1 @@
+debugger;

apps/oxlint/test/fixtures/vite_config_explicit_no_lint_field/options.json

@@ -0,0 +1,4 @@
+{
+  "singleThread": true,
+  "args": ["--config", "vite.config.ts"]
+}

apps/oxlint/test/fixtures/vite_config_explicit_no_lint_field/output.snap.md

@@ -0,0 +1,13 @@
+# Exit code
+1
+
+# stdout
+```
+Failed to parse oxlint configuration file.
+
+  x Expected a `lint` field in the default export of <fixture>/vite.config.ts
+```
+
+# stderr
+```
+```

apps/oxlint/test/fixtures/vite_config_explicit_no_lint_field/vite.config.ts

@@ -0,0 +1,3 @@
+export default {
+  plugins: [],
+};

apps/oxlint/test/fixtures/vite_config_no_lint_field/output.snap.md

@@ -1,11 +1,17 @@
 # Exit code
-1
+0
 
 # stdout
 ```
-Failed to parse oxlint configuration file.
+  ! eslint(no-debugger): `debugger` statement is not allowed
+   ,-[files/test.js:1:1]
+ 1 | debugger;
+   : ^^^^^^^^^
+   `----
+  help: Remove the debugger statement
 
-  x Expected a `lint` field in the default export of <fixture>/vite.config.ts
+Found 1 warning and 0 errors.
+Finished in Xms on 1 file with 93 rules using X threads.
 ```
 
 # stderr

apps/oxlint/test/lsp/lint/__snapshots__/lint.test.ts.snap

@@ -140,6 +140,25 @@ unused-disable-directive-from-config/test.ts
 --------------------"
 `;
 
+exports[`LSP linting > config options > should apply config from vite-config-skip-finds-parent/child/test.js 1`] = `
+"--- FILE -----------
+vite-config-skip-finds-parent/child/test.js
+--- Diagnostics ---------
+  1 | debugger;
+> 2 | if (x == 1) {
+    |       ^^ Warning: Expected === and instead saw ==
+help: Prefer === operator
+  3 | }
+  4 |
+--------------------> 1 | debugger;
+    | ^^^^^^^^^ Error: \`debugger\` statement is not allowed
+help: Remove the debugger statement
+  2 | if (x == 1) {
+  3 | }
+  4 |
+--------------------"
+`;
+
 exports[`LSP linting > initializationOptions > should use custom config path from configPath 1`] = `
 "--- FILE -----------
 custom-config-path/test.ts

apps/oxlint/test/lsp/lint/fixtures/vite-config-skip-finds-parent/.oxlintrc.json

@@ -0,0 +1,6 @@
+{
+  "rules": {
+    "no-debugger": "error",
+    "eqeqeq": "warn"
+  }
+}

apps/oxlint/test/lsp/lint/fixtures/vite-config-skip-finds-parent/child/test.js

@@ -0,0 +1,3 @@
+debugger;
+if (x == 1) {
+}

apps/oxlint/test/lsp/lint/fixtures/vite-config-skip-finds-parent/child/vite.config.ts

@@ -0,0 +1,3 @@
+export default {
+  plugins: [],
+};

apps/oxlint/test/lsp/lint/lint.test.ts

@@ -24,6 +24,7 @@ describe("LSP linting", () => {
       ["config-ts-type-aware/test.ts", "typescript"],
       ["config-ts-nested-type-aware-invalid/nested/test.ts", "typescript"],
       ["unused-disable-directive-from-config/test.ts", "typescript"],
+      ["vite-config-skip-finds-parent/child/test.js", "javascript"],
     ])("should apply config from %s", async (path, languageId) => {
       expect(await lintFixture(FIXTURES_DIR, path, languageId)).toMatchSnapshot();
     });