Merge pull request #999 from ahoppen/lint-warning-by-default

Make linter emit warnings instead of errors by default

Author: ahoppen

Sources/swift-format/Frontend/Frontend.swift

@@ -200,14 +200,21 @@ class Frontend {
  /// Creates a new frontend with the given options.
  ///
  /// - Parameter lintFormatOptions: Options that apply during formatting or linting.
- init(configurationOptions: ConfigurationOptions, lintFormatOptions: LintFormatOptions) {
+ init(
+ configurationOptions: ConfigurationOptions,
+ lintFormatOptions: LintFormatOptions,
+ treatWarningsAsErrors: Bool = false
+ ) {
  self.configurationOptions = configurationOptions
  self.lintFormatOptions = lintFormatOptions
 
  self.diagnosticPrinter = StderrDiagnosticPrinter(
  colorMode: lintFormatOptions.colorDiagnostics.map { $0 ? .on : .off } ?? .auto
  )
- self.diagnosticsEngine = DiagnosticsEngine(diagnosticsHandlers: [diagnosticPrinter.printDiagnostic])
+ self.diagnosticsEngine = DiagnosticsEngine(
+ diagnosticsHandlers: [diagnosticPrinter.printDiagnostic],
+ treatWarningsAsErrors: treatWarningsAsErrors
+ )
  self.configurationProvider = ConfigurationProvider(diagnosticsEngine: self.diagnosticsEngine)
  }
 

Sources/swift-format/Subcommands/Lint.swift

@@ -28,7 +28,7 @@ extension SwiftFormatCommand {
 
  @Flag(
  name: .shortAndLong,
- help: "Fail on warnings. Deprecated: All findings are treated as errors now."
+ help: "Treat all findings as errors instead of warnings."
  )
  var strict: Bool = false
 
@@ -37,15 +37,11 @@ extension SwiftFormatCommand {
 
  func run() throws {
  try performanceMeasurementOptions.printingInstructionCountIfRequested {
- let frontend = LintFrontend(configurationOptions: configurationOptions, lintFormatOptions: lintOptions)
-
- if strict {
- frontend.diagnosticsEngine.emitWarning(
- """
- Running swift-format with --strict is deprecated and will be removed in the future.
- """
- )
- }
+ let frontend = LintFrontend(
+ configurationOptions: configurationOptions,
+ lintFormatOptions: lintOptions,
+ treatWarningsAsErrors: strict
+ )
  frontend.run()
 
  if frontend.diagnosticsEngine.hasErrors {

Sources/swift-format/Utilities/DiagnosticsEngine.swift

@@ -26,20 +26,28 @@ final class DiagnosticsEngine {
  /// A Boolean value indicating whether any warnings were emitted by the diagnostics engine.
  private(set) var hasWarnings: Bool
 
+ /// Whether to upgrade all warnings to errors.
+ private let treatWarningsAsErrors: Bool
+
  /// Creates a new diagnostics engine with the given diagnostic handlers.
  ///
  /// - Parameter diagnosticsHandlers: An array of functions, each of which takes a `Diagnostic` as
  /// its sole argument and returns `Void`. The functions are called whenever a diagnostic is
  /// received by the engine.
- init(diagnosticsHandlers: [(Diagnostic) -> Void]) {
+ init(diagnosticsHandlers: [(Diagnostic) -> Void], treatWarningsAsErrors: Bool = false) {
  self.handlers = diagnosticsHandlers
  self.hasErrors = false
  self.hasWarnings = false
+ self.treatWarningsAsErrors = treatWarningsAsErrors
  }
 
  /// Emits the diagnostic by passing it to the registered handlers, and tracks whether it was an
  /// error or warning diagnostic.
  private func emit(_ diagnostic: Diagnostic) {
+ var diagnostic = diagnostic
+ if treatWarningsAsErrors, diagnostic.severity == .warning {
+ diagnostic.severity = .error
+ }
  switch diagnostic.severity {
  case .error: self.hasErrors = true
  case .warning: self.hasWarnings = true
@@ -135,7 +143,7 @@ final class DiagnosticsEngine {
  /// diagnostics engine and returns it.
  private func diagnosticMessage(for finding: Finding) -> Diagnostic {
  return Diagnostic(
- severity: .error,
+ severity: .warning,
  location: finding.location.map(Diagnostic.Location.init),
  category: "\(finding.category)",
  message: "\(finding.message.text)"