fix(linter): Error when given config options for a lint rule that has no config options defined. (#18809)

Enforce that rules with no config struct/enum raise an error when provided with config options.

For example, the `no-debugger` rule does not take any configuration options. It would silently allow them, but that was an invalid behavior.

```json
{
  "rules": {
    "eslint/no-debugger": ["error", { "some": "option" }]
  }
}
```

With this PR, we get this error:

```
Failed to parse oxlint configuration file.

  x Invalid configuration for rule `no-debugger`:
  |   This rule does not accept configuration options.
```

This prevents misconfiguration from causing problems / confusing behaviors if you try to define a config option on a rule which supports no config options. This is another part of the work for #17854.

There were still a handful of rules not yet migrated over to the `config` defined inside the lint macro. I've worked around that problem by giving them dummy configs for now, and added a test accordingly.

AI Disclosure: Built with help from Raptor Mini + Copilot / Claude Code + Opus. Reviewed and verified by me.

Author: connorshea

apps/oxlint/fixtures/invalid_config_rules_without_config/.oxlintrc.json

@@ -0,0 +1,6 @@
+{
+  "rules": {
+    // `no-debugger` does not accept options; this should error when an options object is provided
+    "eslint/no-debugger": ["error", { "some": "option" }]
+  }
+}

apps/oxlint/fixtures/valid_config_rules_with_dummy_config/.oxlintrc.json

@@ -0,0 +1,16 @@
+{
+  "plugins": ["jest", "react"],
+  "categories": {
+    "correctness": "off"
+  },
+  "rules": {
+    // These rules have `config = Value` in their declare_oxc_lint! macro
+    // to indicate they accept configuration options, even though they use
+    // manual from_configuration implementations.
+    "eslint/no-empty-function": ["error", { "allow": ["functions"] }],
+    "eslint/no-restricted-imports": ["error", { "paths": ["lodash"] }],
+    "eslint/no-warning-comments": ["error", { "terms": ["todo", "fixme"] }],
+    "jest/valid-title": ["error", { "ignoreSpaces": true }],
+    "react/forbid-dom-props": ["error", { "forbid": ["id"] }]
+  }
+}

apps/oxlint/fixtures/valid_config_rules_with_dummy_config/test.js

@@ -0,0 +1,4 @@
+// This file is used to test that rules with dummy config declarations
+// can accept configuration options without errors.
+// The actual content doesn't matter - we're testing config parsing, not linting.
+const x = 1;

apps/oxlint/src/lint.rs

@@ -1362,6 +1362,13 @@ export { redundant };
             .test_and_snapshot(&[]);
     }
 
+    #[test]
+    fn test_invalid_config_rule_without_config_but_options() {
+        Tester::new()
+            .with_cwd("fixtures/invalid_config_rules_without_config".into())
+            .test_and_snapshot(&[]);
+    }
+
     #[test]
     // Ensure the config validation works with vitest/no-hooks, which
     // is an alias of jest/no-hooks.
@@ -1412,6 +1419,17 @@ export { redundant };
         Tester::new().with_cwd("fixtures/valid_complex_config".into()).test_and_snapshot(&[]);
     }
 
+    /// Test that rules with dummy `config = Value` declarations can accept
+    /// configuration options without errors. This test should be removed in
+    /// the future, once these rules have been updated to use proper config
+    /// structs.
+    #[test]
+    fn test_valid_config_rules_with_dummy_config() {
+        Tester::new()
+            .with_cwd("fixtures/valid_config_rules_with_dummy_config".into())
+            .test_and_snapshot(&[]);
+    }
+
     #[test]
     fn test_invalid_config_invalid_config_complex_enum() {
         Tester::new()

apps/oxlint/src/snapshots/[email protected]

@@ -0,0 +1,15 @@
+---
+source: apps/oxlint/src/tester.rs
+---
+########## 
+arguments: 
+working directory: fixtures/invalid_config_rules_without_config
+----------
+Failed to parse oxlint configuration file.
+
+  x Invalid configuration for rule `no-debugger`:
+  |   This rule does not accept configuration options.
+
+----------
+CLI result: InvalidOptionConfig
+----------

apps/oxlint/src/snapshots/[email protected]

@@ -0,0 +1,12 @@
+---
+source: apps/oxlint/src/tester.rs
+---
+########## 
+arguments: 
+working directory: fixtures/valid_config_rules_with_dummy_config
+----------
+Found 0 warnings and 0 errors.
+Finished in <variable>ms on 1 file with 5 rules using 1 threads.
+----------
+CLI result: LintSucceeded
+----------

crates/oxc_linter/src/config/rules.rs

@@ -131,6 +131,18 @@ impl OxlintRules {
                             .find(|r| r.name() == rule_name && r.plugin_name() == plugin_name)
                     });
                     if let Some(rule) = rule {
+                        // If the user provided a non-empty options array for a rule that does not
+                        // declare a `config =` type in its declaration, treat this as an invalid
+                        // configuration and report an error.
+                        if !rule_config.config.is_empty() && !rule.has_config() {
+                            errors.push(OverrideRulesError::RuleConfiguration {
+                                rule_name: rule_config.full_name().into_owned(),
+                                message: "This rule does not accept configuration options."
+                                    .to_string(),
+                            });
+                            continue;
+                        }
+
                         // Configs are stored as `SmallVec<[Value; 1]>`, but `from_configuration` expects
                         // a single `Value` with `Value::Null` being the equivalent of empty config
                         let config = if rule_config.config.is_empty() {
@@ -747,6 +759,35 @@ mod test {
         }
     }
 
+    #[test]
+    fn test_override_rules_errors_for_rules_without_config() {
+        let rules_config = OxlintRules::deserialize(&json!({
+            "eslint/no-debugger": ["error", { "some": "option" }]
+        }))
+        .unwrap();
+
+        let mut builtin_rules = RuleSet::default();
+        let mut external_rules = FxHashMap::default();
+        let mut store = ExternalPluginStore::default();
+
+        match rules_config.override_rules(
+            &mut builtin_rules,
+            &mut external_rules,
+            &RULES,
+            &mut store,
+        ) {
+            Err(errors) => {
+                assert!(errors.len() == 1, "expected one error, got {errors:#?}");
+                assert!(matches!(
+                    &errors[0],
+                    super::OverrideRulesError::RuleConfiguration { rule_name, .. }
+                    if rule_name == "eslint/no-debugger" || rule_name == "no-debugger"
+                ));
+            }
+            Ok(()) => panic!("expected errors from invalid config"),
+        }
+    }
+
     #[test]
     fn test_override_rules_errors_sorted() {
         let rules_config = OxlintRules::deserialize(&json!({
@@ -773,4 +814,51 @@ mod test {
             Ok(()) => panic!("expected errors from invalid configs"),
         }
     }
+
+    /// Test that rules with dummy `config = Value` declarations don't error
+    /// when configuration options are passed to them. These rules have manual
+    /// `from_configuration` implementations but need `config =` in their
+    /// `declare_oxc_lint!` macro to pass the `has_config()` check.
+    #[test]
+    fn test_rules_with_dummy_config_accept_options() {
+        let rules_config = OxlintRules::deserialize(&json!({
+            "eslint/no-empty-function": ["error", { "allow": ["functions"] }],
+            "eslint/no-restricted-imports": ["error", { "paths": ["lodash"] }],
+            "eslint/no-warning-comments": ["error", { "terms": ["todo", "fixme"] }],
+            "jest/valid-title": ["error", { "ignoreSpaces": true }],
+            "react/forbid-dom-props": ["error", { "forbid": ["id"] }]
+        }))
+        .unwrap();
+
+        let mut builtin_rules = RuleSet::default();
+        let mut external_rules = FxHashMap::default();
+        let mut store = ExternalPluginStore::default();
+
+        // These rules should accept configuration without errors
+        rules_config
+            .override_rules(&mut builtin_rules, &mut external_rules, &RULES, &mut store)
+            .expect("rules with dummy config should accept configuration options");
+
+        // Verify the rules were actually added
+        assert!(
+            builtin_rules.iter().any(|(r, _)| r.name() == "no-empty-function"),
+            "no-empty-function should be in the rule set"
+        );
+        assert!(
+            builtin_rules.iter().any(|(r, _)| r.name() == "no-restricted-imports"),
+            "no-restricted-imports should be in the rule set"
+        );
+        assert!(
+            builtin_rules.iter().any(|(r, _)| r.name() == "no-warning-comments"),
+            "no-warning-comments should be in the rule set"
+        );
+        assert!(
+            builtin_rules.iter().any(|(r, _)| r.name() == "valid-title"),
+            "valid-title should be in the rule set"
+        );
+        assert!(
+            builtin_rules.iter().any(|(r, _)| r.name() == "forbid-dom-props"),
+            "forbid-dom-props should be in the rule set"
+        );
+    }
 }