Add a --quiet option.

bin/linter.dart

@@ -6,10 +6,10 @@ import 'dart:io';
 
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:args/args.dart';
+import 'package:linter/src/config.dart';
 import 'package:linter/src/formatter.dart';
 import 'package:linter/src/io.dart';
 import 'package:linter/src/linter.dart';
-import 'package:linter/src/config.dart';
 
 void main(List<String> args) {
   var parser = new ArgParser(allowTrailingOptions: true);
@@ -21,6 +21,7 @@ void main(List<String> args) {
         abbr: "s", negatable: false, help: "Show lint statistics.")
     ..addFlag('visit-transitive-closure',
         help: 'Visit the transitive closure of imported/exported libraries.')
+    ..addFlag('quiet', abbr: 'q', help: "Don't show individual lint errors.")
     ..addOption('config', abbr: 'c', help: 'Use configuration from this file.')
     ..addOption('dart-sdk', help: 'Custom path to a Dart SDK.')
     ..addOption('package-root',
@@ -84,7 +85,8 @@ void main(List<String> args) {
         errors, lintOptions.filter, outSink,
         fileCount: filesToLint.length,
         fileRoot: commonRoot,
-        showStatistics: stats);
+        showStatistics: stats,
+        quiet: options['quiet']);
     reporter.write();
   } catch (err, stack) {
     errorSink.writeln('''An error occurred while linting

lib/src/formatter.dart

@@ -54,11 +54,13 @@ String shorten(String fileRoot, String fullName) {
 class DetailedReporter extends SimpleFormatter {
   DetailedReporter(
       Iterable<AnalysisErrorInfo> errors, LintFilter filter, IOSink out,
-      {int fileCount, String fileRoot, bool showStatistics: false})
+      {int fileCount, String fileRoot, bool showStatistics: false,
+      quiet: false})
       : super(errors, filter, out,
           fileCount: fileCount,
           fileRoot: fileRoot,
-          showStatistics: showStatistics);
+          showStatistics: showStatistics,
+          quiet: quiet);
 
   @override
   writeLint(AnalysisError error, {int offset, int line, int column}) {
@@ -76,12 +78,13 @@ class DetailedReporter extends SimpleFormatter {
 
 abstract class ReportFormatter {
   factory ReportFormatter(
-          Iterable<AnalysisErrorInfo> errors, LintFilter filter, IOSink out,
-          {int fileCount, String fileRoot, bool showStatistics: false}) =>
-      new DetailedReporter(errors, filter, out,
-          fileCount: fileCount,
-          fileRoot: fileRoot,
-          showStatistics: showStatistics);
+      Iterable<AnalysisErrorInfo> errors, LintFilter filter, IOSink out,
+      {int fileCount, String fileRoot, bool showStatistics: false,
+      bool quiet: false}) => new DetailedReporter(errors, filter, out,
+      fileCount: fileCount,
+      fileRoot: fileRoot,
+      showStatistics: showStatistics,
+      quiet: quiet);
 
   write();
 }
@@ -98,14 +101,15 @@ class SimpleFormatter implements ReportFormatter {
   final int fileCount;
   final String fileRoot;
   final bool showStatistics;
+  final bool quiet;
 
   /// Cached for the purposes of statistics report formatting.
   int _summaryLength = 0;
 
   Map<String, int> stats = <String, int>{};
 
-  SimpleFormatter(this.errors, this.filter, this.out,
-      {this.fileCount, this.fileRoot, this.showStatistics: false});
+  SimpleFormatter(this.errors, this.filter, this.out, {this.fileCount,
+      this.fileRoot, this.showStatistics: false, this.quiet: false});
 
   /// Override to influence error sorting
   int compare(AnalysisError error1, AnalysisError error2) {
@@ -148,10 +152,15 @@ class SimpleFormatter implements ReportFormatter {
         filteredLintCount++;
       } else {
         ++errorCount;
-        _writeLint(e, info.lineInfo);
+        if (!quiet) {
+          _writeLint(e, info.lineInfo);
+        }
+        _recordStats(e);
       }
     }));
-    out.writeln();
+    if (!quiet) {
+      out.writeln();
+    }
   }
 
   void writeStatistics() {
@@ -193,6 +202,5 @@ class SimpleFormatter implements ReportFormatter {
     var column = lineInfo.getLocation(offset).columnNumber;
 
     writeLint(error, offset: offset, column: column, line: line);
-    _recordStats(error);
   }
 }