Fix an issue with duplicate reported analysis errors.

pkg/analyzer_cli/lib/src/driver.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.driver;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io' as io;
 
@@ skipping 20 matching lines @@
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/generated/utilities_general.dart'
     show PerformanceTag;
 import 'package:analyzer/src/source/source_resource.dart';
 import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
 import 'package:analyzer/src/summary/summary_sdk.dart' show SummaryBasedDartSdk;
 import 'package:analyzer_cli/src/analyzer_impl.dart';
 import 'package:analyzer_cli/src/build_mode.dart';
 import 'package:analyzer_cli/src/error_formatter.dart';
+import 'package:analyzer_cli/src/error_severity.dart';
 import 'package:analyzer_cli/src/options.dart';
 import 'package:analyzer_cli/src/perf_report.dart';
 import 'package:analyzer_cli/starter.dart' show CommandLineStarter;
 import 'package:linter/src/rules.dart' as linter;
 import 'package:package_config/discovery.dart' as pkg_discovery;
 import 'package:package_config/packages.dart' show Packages;
 import 'package:package_config/packages_file.dart' as pkgfile show parse;
 import 'package:package_config/src/packages_impl.dart' show MapPackages;
 import 'package:path/path.dart' as path;
 import 'package:plugin/manager.dart';
@@ skipping 174 matching lines @@
       if (analysisDriver == null) {
         context.applyChanges(changeSet);
       }
     }
 
     // Analyze the libraries.
     ErrorSeverity allResult = ErrorSeverity.NONE;
     List<Uri> libUris = <Uri>[];
     Set<Source> partSources = new Set<Source>();
 
+    SeverityProcessor defaultSeverityProcessor = (AnalysisError error) {
+      return determineProcessedSeverity(
+          error, options, _context.analysisOptions);
+    };
+
+    // We currently print out to stderr to ensure that when in batch mode we
+    // print to stderr, this is because the prints from batch are made to
+    // stderr. The reason that options.shouldBatch isn't used is because when
+    // the argument flags are constructed in BatchRunner and passed in from
+    // batch mode which removes the batch flag to prevent the "cannot have the
+    // batch flag and source file" error message.
+    ErrorFormatter formatter;
+    if (options.machineFormat) {
+      formatter = new MachineErrorFormatter(errorSink, options, stats,
+          severityProcessor: defaultSeverityProcessor);
+    } else {
+      formatter = new HumanErrorFormatter(outSink, options, stats,
+          severityProcessor: defaultSeverityProcessor);
+    }
+
     for (Source source in sourcesToAnalyze) {
       SourceKind sourceKind = analysisDriver != null
           ? await analysisDriver.getSourceKind(source.fullName)
           : context.computeKindOf(source);
       if (sourceKind == SourceKind.PART) {
         partSources.add(source);
         continue;
       }
-      // TODO(devoncarew): Analyzing each source individually causes errors to
-      // be reported multiple times (#25697).
-      ErrorSeverity status = await _runAnalyzer(source, options);
+      ErrorSeverity status = await _runAnalyzer(source, options, formatter);
       allResult = allResult.max(status);
       libUris.add(source.uri);
     }
 
+    formatter.flush();
+
     // Check that each part has a corresponding source in the input list.
     for (Source partSource in partSources) {
       bool found = false;
       if (analysisDriver != null) {
         var partFile =
             analysisDriver.fsState.getFileForPath(partSource.fullName);
         if (libUris.contains(partFile.library?.uri)) {
           found = true;
         }
       } else {
@@ skipping 424 matching lines @@
     plugins.addAll(AnalysisEngine.instance.requiredPlugins);
     plugins.addAll(_userDefinedPlugins);
 
     ExtensionManager manager = new ExtensionManager();
     manager.processPlugins(plugins);
 
     linter.registerLintRules();
   }
 
   /// Analyze a single source.
-  Future<ErrorSeverity> _runAnalyzer(
-      Source source, CommandLineOptions options) async {
+  Future<ErrorSeverity> _runAnalyzer(Source source, CommandLineOptions options,
+      ErrorFormatter formatter) async {
     int startTime = currentTimeMillis;
     AnalyzerImpl analyzer = new AnalyzerImpl(_context.analysisOptions, _context,
         analysisDriver, source, options, stats, startTime);
-    ErrorSeverity errorSeverity = await analyzer.analyze();
+    ErrorSeverity errorSeverity = await analyzer.analyze(formatter);
     if (errorSeverity == ErrorSeverity.ERROR) {
       io.exitCode = errorSeverity.ordinal;
     }
     if (options.warningsAreFatal && errorSeverity == ErrorSeverity.WARNING) {
       io.exitCode = errorSeverity.ordinal;
     }
     return errorSeverity;
   }
 
   void _setupSdk(CommandLineOptions options, bool useSummaries,
@@ skipping 202 matching lines @@
     for (var package in packages) {
       var packageName = path.basename(package.path);
       var realPath = package.resolveSymbolicLinksSync();
       result[packageName] = [
         PhysicalResourceProvider.INSTANCE.getFolder(realPath)
       ];
     }
     return result;
   }
 }