feat(linter): read rule configuration from json

crates/oxc_linter/src/lib.rs

@@ -7,7 +7,7 @@ mod context;
 mod rule;
 mod rules;
 
-use std::rc::Rc;
+use std::{fs, rc::Rc};
 
 use oxc_diagnostics::Error;
 pub(crate) use oxc_semantic::AstNode;
@@ -27,7 +27,20 @@ impl Linter {
     #[must_use]
     #[allow(clippy::new_without_default)]
     pub fn new() -> Self {
-        Self { rules: RULES.to_vec() }
+        let rules_config = Self::read_rules_configuration();
+        let rules = rules_config.map_or_else(
+            || RULES.to_vec(),
+            |rules_config| {
+                RULES
+                    .iter()
+                    .map(|rule| {
+                        let value = rules_config.get(rule.name());
+                        rule.read_json(value.cloned())
+                    })
+                    .collect()
+            },
+        );
+        Self { rules }
     }
 
     #[must_use]
@@ -47,4 +60,12 @@ impl Linter {
 
         ctx.into_diagnostics()
     }
+
+    fn read_rules_configuration() -> Option<serde_json::Map<String, serde_json::Value>> {
+        fs::read_to_string(".eslintrc.json")
+            .ok()
+            .and_then(|s| serde_json::from_str(&s).ok())
+            .and_then(|v: serde_json::Value| v.get("rules").cloned())
+            .and_then(|v| v.as_object().cloned())
+    }
 }

crates/oxc_linter/src/rules.rs

@@ -27,13 +27,13 @@ impl RuleEnum {
         }
     }
 
-    pub fn from_json(&self, maybe_value: Option<serde_json::Value>) -> Self {
+    pub fn read_json(&self, maybe_value: Option<serde_json::Value>) -> Self {
         match self {
             Self::NoDebugger(_) => {
-                RuleEnum::NoDebugger(maybe_value.map(NoDebugger::from_json).unwrap_or_default())
+                Self::NoDebugger(maybe_value.map(NoDebugger::from_json).unwrap_or_default())
             }
             Self::NoEmpty(_) => {
-                RuleEnum::NoEmpty(maybe_value.map(NoEmpty::from_json).unwrap_or_default())
+                Self::NoEmpty(maybe_value.map(NoEmpty::from_json).unwrap_or_default())
             }
         }
     }

crates/oxc_linter/src/rules/no_empty.rs

@@ -26,7 +26,7 @@ impl Rule for NoEmpty {
         Self {
             allow_empty_catch: obj
                 .and_then(|v| v.get("allowEmptyCatch"))
-                .and_then(|v| v.as_bool())
+                .and_then(serde_json::Value::as_bool)
                 .unwrap_or_default(),
         }
     }

crates/oxc_linter/src/tester.rs

@@ -65,7 +65,7 @@ impl Tester {
         let semantic = SemanticBuilder::new().build(program, ret.trivias);
         let semantic = std::rc::Rc::new(semantic);
         let rule = RULES.iter().find(|rule| rule.name() == self.rule_name).unwrap();
-        let rule = rule.from_json(config);
+        let rule = rule.read_json(config);
         let diagnostics = Linter::from_rules(vec![rule]).run(&semantic);
         if diagnostics.is_empty() {
             return true;