Print violations in realtime if progress with an output file (#4362)

CHANGELOG.md

@@ -146,6 +146,9 @@
   only differ in trivia.  
   [SimplyDanny](https://github.com/SimplyDanny)
 
+* Print violations in realtime if `--progress` and `--output` are both set.  
+  [JP Simard](https://github.com/jpsim)
+
 #### Bug Fixes
 
 * Respect `validates_start_with_lowercase` option when linting function names.  

Source/swiftlint/Helpers/LintOrAnalyzeCommand.swift

@@ -272,7 +272,7 @@ private class LintOrAnalyzeResultBuilder {
     }
 
     func report(violations: [StyleViolation], realtimeCondition: Bool) {
-        if (reporter.isRealtime && !options.progress) == realtimeCondition {
+        if (reporter.isRealtime && (!options.progress || options.output != nil)) == realtimeCondition {
             let report = reporter.generateReport(violations)
             if !report.isEmpty {
                 options.writeToOutput(report)