"IdiomAuditor: SwiftLint's Best Rules, Native and AST-Based"

The head of SwiftLint’s usage, rebuilt as native AST rules — so you can drop a tool instead of adding one.

---

The goal here was substitutional, not additive: adopting quality-gate should mean dropping a tool, not running one more. IdiomAuditor reimplements the most-used SwiftLint rules — about twenty of them — as native SwiftSyntax checks, so the style layer lives in the same gate as the correctness layer.

The kinds of rule

Empty-count (x.count == 0 → x.isEmpty), the redundant-syntax family, syntactic sugar (Array → [Int]), shorthand operators, identifier and type naming, TODO-ticket policy, file/function/line length, the whitespace family, unused closure parameters, implicit getters, redundant String enum values, legacy random, contains-over-first.

// ❌ if array.count == 0        ✅ if array.isEmpty
// ❌ let x: Array
            
               = [] ✅ let x: [Int] = [] // ❌ x = x + 1 ✅ x += 1 
            

Advisory, with safe autofix

Idiom rules are advisory — notes by default, because the gate blocks on correctness, not whitespace (you can escalate them in config if you want). Many carry a safe-subset suggestedFix, verified by round-trip tests: apply the fix, reparse, confirm the rule now stays silent. And there’s a migration path — quality-gate import-swiftlint reads your .swiftlint.yml, maps enabled rules to their native equivalents (thresholds carried over), translates custom_rules verbatim, and prints an honest report of what it couldn’t map. Even the migration tells the truth about its gaps.

// idiom:exempt suppresses a site — recorded as an override, never silent.

Try it

quality-gate --check idiom
quality-gate import-swiftlint      # migrate an existing .swiftlint.yml

---

Source: github.com/jpurnell/quality-gate-swift