feat(language_server): auto detect oxlint config

crates/oxc_language_server/src/main.rs

@@ -1,14 +1,14 @@
 mod linter;
 
-use std::{fmt::Debug, path::PathBuf, str::FromStr};
-
 use dashmap::DashMap;
 use futures::future::join_all;
 use globset::Glob;
 use ignore::gitignore::Gitignore;
-use log::{debug, error, info};
+use log::{debug, error, info, warn};
 use oxc_linter::{FixKind, LinterBuilder, Oxlintrc};
 use serde::{Deserialize, Serialize};
+use std::path::{Path, PathBuf};
+use std::{fmt::Debug, str::FromStr};
 use tokio::sync::{Mutex, OnceCell, RwLock, SetError};
 use tower_lsp::{
     jsonrpc::{Error, ErrorCode, Result},
@@ -47,12 +47,12 @@ enum Run {
 struct Options {
     run: Run,
     enable: bool,
-    config_path: String,
+    config_path: Option<String>,
 }
 
 impl Default for Options {
     fn default() -> Self {
-        Self { enable: true, run: Run::default(), config_path: ".eslintrc".into() }
+        Self { enable: true, run: Run::default(), config_path: None }
     }
 }
 
@@ -68,11 +68,44 @@ impl Options {
         }
     }
 
-    fn get_config_path(&self) -> Option<PathBuf> {
-        if self.config_path.is_empty() {
+    fn get_config_path(&self, root_path: &Path) -> Option<PathBuf> {
+        let Some(config_path) = &self.config_path else {
+            // no config file is provided, let search in the root_path for one
+            let search_configs = vec![
+                "oxlintrc.json",
+                "oxlint.json",
+                ".oxlintrc.json",
+                ".oxlint.json",
+                ".oxlintrc",
+                ".eslintrc",
+                ".eslintrc.json",
+            ];
+
+            for search_config in search_configs {
+                let config_path = root_path.join(search_config);
+
+                if config_path.exists() {
+                    info!("Automatically detected config {config_path:?}");
+                    return Some(config_path);
+                }
+            }
+
+            return None;
+        };
+
+        // config path is provided and is empty, e.g "oxc.configPath": ""
+        if config_path.is_empty() {
             None
         } else {
-            Some(PathBuf::from(&self.config_path))
+            // provided config path is not empty
+            let config_path = root_path.join(config_path);
+
+            if config_path.exists() {
+                return Some(config_path);
+            }
+
+            warn!("could not find oxlint config file {:?}", config_path);
+            None
         }
     }
 }
@@ -362,11 +395,9 @@ impl Backend {
         let Ok(root_path) = uri.to_file_path() else {
             return;
         };
-        let mut config_path = None;
-        let config = root_path.join(self.options.lock().await.get_config_path().unwrap());
-        if config.exists() {
-            config_path = Some(config);
-        }
+
+        let config_path = self.options.lock().await.get_config_path(&root_path);
+
         if let Some(config_path) = config_path {
             let mut linter = self.server_linter.write().await;
             *linter = ServerLinter::new_with_linter(

editors/vscode/client/config.ts

@@ -8,7 +8,7 @@ export class ConfigService implements Config, IDisposable {
   private _runTrigger!: Trigger;
   private _enable!: boolean;
   private _trace!: TraceLevel;
-  private _configPath!: string;
+  private _configPath!: string | undefined;
   private _binPath: string | undefined;
 
   public onConfigChange:
@@ -31,7 +31,7 @@ export class ConfigService implements Config, IDisposable {
     this._runTrigger = this._inner.get<Trigger>('lint.run') || 'onType';
     this._enable = this._inner.get<boolean>('enable') ?? true;
     this._trace = this._inner.get<TraceLevel>('trace.server') || 'off';
-    this._configPath = this._inner.get<string>('configPath') || '.eslintrc';
+    this._configPath = this._inner.get<string>('configPath');
     this._binPath = this._inner.get<string>('path.server');
   }
 
@@ -68,11 +68,11 @@ export class ConfigService implements Config, IDisposable {
       .update('trace.server', value);
   }
 
-  get configPath(): string {
+  get configPath(): string | undefined {
     return this._configPath;
   }
 
-  set configPath(value: string) {
+  set configPath(value: string | undefined) {
     this._configPath = value;
     workspace
       .getConfiguration(ConfigService._namespace)
@@ -116,7 +116,7 @@ type Trigger = 'onSave' | 'onType';
 type TraceLevel = 'off' | 'messages' | 'verbose';
 
 interface LanguageServerConfig {
-  configPath: string;
+  configPath: string | undefined;
   enable: boolean;
   run: Trigger;
 }
@@ -150,9 +150,9 @@ interface Config {
    *
    * `oxc.configPath`
    *
-   * @default ".eslintrc"
+   * @default undefined
    */
-  configPath: string;
+  configPath: string | undefined;
   /**
    * Path to LSP binary
    * `oxc.path.server`

editors/vscode/package.json

@@ -90,10 +90,10 @@
           "description": "Traces the communication between VS Code and the language server."
         },
         "oxc.configPath": {
-          "type": "string",
+          "type": ["string", "null"],
           "scope": "window",
-          "default": ".eslintrc",
-          "description": "Path to ESlint configuration."
+          "default": null,
+          "description": "Path to oxlint configuration."
         },
         "oxc.path.server": {
           "type": "string",