feat(oxlint): implement --print-config cli option

apps/oxlint/src/command/lint.rs

@@ -37,6 +37,10 @@ pub struct LintCommand {
     #[bpaf(long("rules"), switch, hide_usage)]
     pub list_rules: bool,
 
+    /// print a generated configuration file
+    #[bpaf(long("print-config"), switch, hide_usage)]
+    pub print_config: bool,
+
     #[bpaf(external)]
     pub misc_options: MiscOptions,
 

apps/oxlint/src/lint/mod.rs

@@ -41,6 +41,7 @@ impl Runner for LintRunner {
             enable_plugins,
             output_options,
             misc_options,
+            print_config,
             ..
         } = self.options;
 
@@ -136,6 +137,11 @@ impl Runner for LintRunner {
         let mut diagnostic_service =
             Self::get_diagnostic_service(&warning_options, &output_options, &misc_options);
 
+        if print_config {
+            let mut stdout = BufWriter::new(std::io::stdout());
+            lint_service.linter().print_config(&mut stdout);
+            return CliRunResult::None;
+        }
         // Spawn linting in another thread so diagnostics can be printed immediately from diagnostic_service.run.
         rayon::spawn({
             let tx_error = diagnostic_service.sender().clone();
@@ -512,4 +518,21 @@ mod test {
         assert_eq!(result.number_of_files, 1);
         assert_eq!(result.number_of_errors, 1);
     }
+
+    #[test]
+    fn test_print_config() {
+        let args = &[
+            "-W",
+            "correctness",
+            "-A",
+            "no-debugger",
+            "fixtures/linter/debugger.js",
+            "--print-config",
+        ];
+        let options = lint_command().run_inner(args).unwrap();
+        match LintRunner::new(options).run() {
+            CliRunResult::None => {}
+            other => panic!("{other:?}"),
+        }
+    }
 }

crates/oxc_linter/src/config/env.rs

@@ -1,12 +1,12 @@
 use rustc_hash::FxHashMap;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 use std::{borrow::Borrow, hash::Hash};
 
 /// Predefine global variables.
 // TODO: list the keys we support
 // <https://eslint.org/docs/v8.x/use/configure/language-options#specifying-environments>
-#[derive(Debug, Clone, Deserialize, JsonSchema)]
+#[derive(Debug, Clone, Deserialize, JsonSchema, Serialize)]
 pub struct OxlintEnv(FxHashMap<String, bool>);
 
 impl OxlintEnv {

crates/oxc_linter/src/config/globals.rs

@@ -1,14 +1,14 @@
 use rustc_hash::FxHashMap;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 /// Add or remove global variables.
 // <https://eslint.org/docs/v8.x/use/configure/language-options#using-configuration-files-1>
-#[derive(Debug, Default, Deserialize, JsonSchema)]
+#[derive(Debug, Default, Deserialize, JsonSchema, Serialize)]
 pub struct OxlintGlobals(FxHashMap<String, GlobalValue>);
 
 // TODO: support deprecated `false`
-#[derive(Debug, Eq, PartialEq, Deserialize, JsonSchema)]
+#[derive(Debug, Eq, PartialEq, Deserialize, JsonSchema, Serialize)]
 #[serde(rename_all = "lowercase")]
 pub enum GlobalValue {
     Readonly,

crates/oxc_linter/src/config/mod.rs

@@ -8,7 +8,7 @@ use std::path::Path;
 use oxc_diagnostics::OxcDiagnostic;
 use rustc_hash::FxHashSet;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 pub use self::{
     env::OxlintEnv,
@@ -51,7 +51,7 @@ use crate::{
 ///   }
 ///  }
 /// ```
-#[derive(Debug, Default, Deserialize, JsonSchema)]
+#[derive(Debug, Default, Deserialize, JsonSchema, Serialize)]
 #[serde(default)]
 pub struct OxlintConfig {
     /// See [Oxlint Rules](./rules)

crates/oxc_linter/src/config/rules.rs

@@ -5,10 +5,10 @@ use rustc_hash::FxHashMap;
 use schemars::{gen::SchemaGenerator, schema::Schema, JsonSchema};
 use serde::{
     de::{self, Deserializer, Visitor},
-    Deserialize,
+    Deserialize, Serialize,
 };
 
-use crate::AllowWarnDeny;
+use crate::{AllowWarnDeny, RuleWithSeverity};
 
 // TS type is `Record<string, RuleConf>`
 //   - type SeverityConf = 0 | 1 | 2 | "off" | "warn" | "error";
@@ -25,6 +25,21 @@ pub struct ESLintRule {
     pub config: Option<serde_json::Value>,
 }
 
+impl OxlintRules {
+    pub fn from_rules(rules: Vec<RuleWithSeverity>) -> Self {
+        let rules = rules
+            .into_iter()
+            .map(|rule| ESLintRule {
+                plugin_name: rule.plugin_name().to_string(),
+                rule_name: rule.name().to_string(),
+                severity: rule.severity,
+                config: None,
+            })
+            .collect();
+        Self(rules)
+    }
+}
+
 impl JsonSchema for OxlintRules {
     fn schema_name() -> String {
         "OxlintRules".to_owned()
@@ -83,6 +98,28 @@ impl<'de> Deserialize<'de> for OxlintRules {
     }
 }
 
+impl Serialize for OxlintRules {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        let rules = self.0.iter().map(|rule| {
+            let key = format!("{}/{}", rule.plugin_name, rule.rule_name);
+            let value = match &rule.config {
+                Some(config) => serde_json::Value::Array(vec![
+                    serde_json::to_value(rule.severity).unwrap(),
+                    config.clone(),
+                ]),
+                None => serde_json::to_value(rule.severity).unwrap(),
+            };
+            (key, value)
+        });
+
+        let map = rules.collect::<FxHashMap<_, _>>();
+        map.serialize(serializer)
+    }
+}
+
 fn parse_rule_key(name: &str) -> (String, String) {
     let Some((plugin_name, rule_name)) = name.split_once('/') else {
         return ("eslint".to_string(), name.to_string());

crates/oxc_linter/src/config/settings/jsdoc.rs

@@ -2,10 +2,10 @@ use std::borrow::Cow;
 
 use rustc_hash::FxHashMap;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 // <https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/settings.md>
-#[derive(Debug, Deserialize, JsonSchema)]
+#[derive(Debug, Deserialize, JsonSchema, Serialize)]
 pub struct JSDocPluginSettings {
     /// For all rules but NOT apply to `check-access` and `empty-tags` rule
     #[serde(default, rename = "ignorePrivate")]
@@ -184,7 +184,7 @@ fn default_true() -> bool {
     true
 }
 
-#[derive(Clone, Debug, Deserialize, JsonSchema)]
+#[derive(Clone, Debug, Deserialize, JsonSchema, Serialize)]
 #[serde(untagged)]
 enum TagNamePreference {
     TagNameOnly(String),

crates/oxc_linter/src/config/settings/jsx_a11y.rs

@@ -1,10 +1,10 @@
 use oxc_span::CompactStr;
 use rustc_hash::FxHashMap;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 // <https://github.com/jsx-eslint/eslint-plugin-jsx-a11y#configurations>
-#[derive(Debug, Deserialize, Default, JsonSchema)]
+#[derive(Debug, Deserialize, Default, JsonSchema, Serialize)]
 pub struct JSXA11yPluginSettings {
     #[serde(rename = "polymorphicPropName")]
     pub polymorphic_prop_name: Option<CompactStr>,

crates/oxc_linter/src/config/settings/mod.rs

@@ -4,15 +4,15 @@ mod next;
 mod react;
 
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 use self::{
     jsdoc::JSDocPluginSettings, jsx_a11y::JSXA11yPluginSettings, next::NextPluginSettings,
     react::ReactPluginSettings,
 };
 
 /// Shared settings for plugins
-#[derive(Debug, Deserialize, Default, JsonSchema)]
+#[derive(Debug, Deserialize, Default, JsonSchema, Serialize)]
 pub struct OxlintSettings {
     #[serde(default)]
     #[serde(rename = "jsx-a11y")]

crates/oxc_linter/src/config/settings/next.rs

@@ -1,9 +1,9 @@
 use std::borrow::Cow;
 
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
-#[derive(Debug, Deserialize, Default, JsonSchema)]
+#[derive(Debug, Deserialize, Default, JsonSchema, Serialize)]
 pub struct NextPluginSettings {
     #[serde(default)]
     #[serde(rename = "rootDir")]
@@ -21,7 +21,7 @@ impl NextPluginSettings {
 
 // Deserialize helper types
 
-#[derive(Clone, Debug, Deserialize, PartialEq, JsonSchema)]
+#[derive(Clone, Debug, Deserialize, PartialEq, JsonSchema, Serialize)]
 #[serde(untagged)]
 enum OneOrMany<T> {
     One(T),

crates/oxc_linter/src/config/settings/react.rs

@@ -2,10 +2,10 @@ use std::borrow::Cow;
 
 use oxc_span::CompactStr;
 use schemars::JsonSchema;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 
 // <https://github.com/jsx-eslint/eslint-plugin-react#configuration-legacy-eslintrc->
-#[derive(Debug, Deserialize, Default, JsonSchema)]
+#[derive(Debug, Deserialize, Default, JsonSchema, Serialize)]
 pub struct ReactPluginSettings {
     #[serde(default)]
     #[serde(rename = "formComponents")]
@@ -30,7 +30,7 @@ impl ReactPluginSettings {
 
 // Deserialize helper types
 
-#[derive(Clone, Debug, Deserialize, JsonSchema)]
+#[derive(Clone, Debug, Deserialize, JsonSchema, Serialize)]
 #[serde(untagged)]
 enum CustomComponent {
     NameOnly(CompactStr),

crates/oxc_linter/src/lib.rs

@@ -26,7 +26,7 @@ use oxc_diagnostics::Error;
 use oxc_semantic::{AstNode, Semantic};
 
 pub use crate::{
-    config::OxlintConfig,
+    config::{OxlintConfig, OxlintRules},
     context::LintContext,
     fixer::FixKind,
     frameworks::FrameworkFlags,
@@ -142,6 +142,24 @@ impl Linter {
         rules.into_iter().flat_map(|(_, ctx)| ctx.into_message()).collect::<Vec<_>>()
     }
 
+    /// # Panics
+    pub fn print_config<W: Write>(&self, writer: &mut W) {
+        // merge rules with eslint_config
+        let additional_rules = OxlintRules::from_rules(self.rules.clone());
+        let rules = serde_json::to_value(additional_rules).unwrap();
+        let mut config = serde_json::to_value(self.eslint_config.as_ref()).unwrap();
+        config
+            .get_mut("rules")
+            .unwrap()
+            .as_object_mut()
+            .unwrap()
+            .extend(rules.as_object().unwrap().clone());
+
+        let json = serde_json::to_string_pretty(&config).unwrap();
+        // serialize the config to json and print it
+        writeln!(writer, "{json}").unwrap();
+    }
+
     /// # Panics
     pub fn print_rules<W: Write>(writer: &mut W) {
         let table = RuleTable::new();

crates/oxc_linter/src/options.rs

@@ -3,6 +3,7 @@ use std::{convert::From, path::PathBuf};
 use oxc_diagnostics::{Error, OxcDiagnostic, Severity};
 use rustc_hash::FxHashSet;
 use schemars::{schema::SchemaObject, JsonSchema};
+use serde::Serialize;
 use serde_json::{Number, Value};
 
 use crate::{
@@ -165,7 +166,8 @@ impl LintOptions {
     }
 }
 
-#[derive(Debug, Clone, Copy, Eq, PartialEq)]
+#[derive(Debug, Clone, Copy, Eq, PartialEq, Serialize)]
+#[serde(rename_all = "lowercase")]
 pub enum AllowWarnDeny {
     Allow, // Off
     Warn,  // Warn
@@ -251,7 +253,7 @@ impl JsonSchema for AllowWarnDeny {
         int_schema.number().maximum = Some(2.0);
         int_schema.metadata().description = Some(
             "Oxlint rule.
-    
+
 - 0: Turn off the rule.
 - 1: Turn the rule on as a warning (doesn't affect exit code).
 - 2: Turn the rule on as an error (will exit with a failure code)."