feat(lint): support --rules --json (#8384)

This commit adds support for "--json" flag in combination
with "--rules". List of rules is serialized to JSON and printed.

cli/lint.rs

@@ -96,15 +96,30 @@ pub async fn lint_files(
   Ok(())
 }
 
-pub fn print_rules_list() {
+fn rule_to_json(rule: Box<dyn LintRule>) -> serde_json::Value {
+  serde_json::json!({
+    "code": rule.code(),
+    "tags": rule.tags(),
+    "docs": rule.docs(),
+  })
+}
+
+pub fn print_rules_list(json: bool) {
   let lint_rules = rules::get_recommended_rules();
 
+  if json {
+    let json_rules: Vec<serde_json::Value> =
+      lint_rules.into_iter().map(rule_to_json).collect();
+    let json_str = serde_json::to_string_pretty(&json_rules).unwrap();
+    println!("{}", json_str);
+  } else {
     // The rules should still be printed even if `--quiet` option is enabled,
     // so use `println!` here instead of `info!`.
     println!("Available rules:");
     for rule in lint_rules {
       println!(" - {}", rule.code());
     }
+  }
 }
 
 fn create_linter(syntax: Syntax, rules: Vec<Box<dyn LintRule>>) -> Linter {

cli/main.rs

@@ -229,7 +229,7 @@ async fn lint_command(
   }
 
   if list_rules {
-    lint::print_rules_list();
+    lint::print_rules_list(json);
     return Ok(());
   }