add --x-package-warnings-prefix option to dartanalyzer

pkg/analyzer_cli/lib/src/error_formatter.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer_cli.src.error_formatter;
 
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer_cli/src/options.dart';
 
 /// Returns the given error's severity.
 ProcessedSeverity _identity(AnalysisError error) =>
     new ProcessedSeverity(error.errorCode.errorSeverity);
 
 /// Returns desired severity for the given [error] (or `null` if it's to be
 /// suppressed).
 typedef ProcessedSeverity _SeverityProcessor(AnalysisError error);
 
 /// Helper for formatting [AnalysisError]s.
 /// The two format options are a user consumable format and a machine consumable
 /// format.
 class ErrorFormatter {
+  /// The total number of errors sent to [formatErrors].
+  static int get inputErrorCount => _inputErrorCount;
+  static int _inputErrorCount = 0;

[Brian Wilkerson, 2016/03/18 14:13:17]

This looks like it's duplicating some work that Phil recently did (and might not
be committed yet. You should coordinate with him on it.

[skybrian, 2016/03/18 22:32:44]

It's a slightly different statistic. Merged into AnalysisStats.

+
   final StringSink out;
   final CommandLineOptions options;
   final _SeverityProcessor processSeverity;
 
   ErrorFormatter(this.out, this.options, [this.processSeverity = _identity]);
 
   /// Compute the severity for this [error] or `null` if this error should be
   /// filtered.
   ErrorSeverity computeSeverity(AnalysisError error) =>
       processSeverity(error)?.severity;
@@ skipping 42 matching lines @@
 
       // [warning] 'foo' is not a... (/Users/.../tmp/foo.dart, line 1, col 2)
       out.write('[$errorType] ${error.message} ');
       out.write('(${source.fullName}');
       out.write(', line ${location.lineNumber}, col ${location.columnNumber})');
     }
     out.writeln();
   }
 
   void formatErrors(List<AnalysisErrorInfo> errorInfos) {
+    _inputErrorCount += errorInfos.length;
+
     var errors = new List<AnalysisError>();
     var errorToLine = new Map<AnalysisError, LineInfo>();
     for (AnalysisErrorInfo errorInfo in errorInfos) {
       for (AnalysisError error in errorInfo.errors) {
         if (computeSeverity(error) != null) {
           errors.add(error);
           errorToLine[error] = errorInfo.lineInfo;
         }
       }
     }
@@ skipping 115 matching lines @@
     }
   }
 }
 
 /// A severity with awareness of whether it was overriden by a processor.
 class ProcessedSeverity {
   ErrorSeverity severity;
   bool overridden;
   ProcessedSeverity(this.severity, [this.overridden = false]);
 }