Add --x-perf-report flag to the dartanalyzer command

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';
 
 import 'package:analyzer/file_system/file_system.dart' as fileSystem;
 import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analyzer/plugin/options.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
 import 'package:analyzer/source/package_map_provider.dart';
 import 'package:analyzer/source/package_map_resolver.dart';
 import 'package:analyzer/source/pub_package_map_provider.dart';
 import 'package:analyzer/source/sdk_ext.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/interner.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/java_io.dart';
 import 'package:analyzer/src/generated/sdk_io.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart';
+import 'package:analyzer/src/generated/utilities_general.dart'
+    show PerformanceTag;
 import 'package:analyzer/src/services/lint.dart';
 import 'package:analyzer/src/task/options.dart';
 import 'package:analyzer_cli/src/analyzer_impl.dart';
 import 'package:analyzer_cli/src/options.dart';
 import 'package:linter/src/plugin/linter_plugin.dart';
 import 'package:package_config/discovery.dart' as pkgDiscovery;
 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;
@@ skipping 43 matching lines @@
   /// *Visible for testing.*
   AnalysisContext get context => _context;
 
   /// Set the [plugins] that are defined outside the `analyzer_cli` package.
   void set userDefinedPlugins(List<Plugin> plugins) {
     _userDefinedPlugins = plugins == null ? <Plugin>[] : plugins;
   }
 
   /// Use the given command-line [args] to start this analysis driver.
   void start(List<String> args) {
+    int startTime = new DateTime.now().millisecondsSinceEpoch;
+
     StringUtilities.INTERNER = new MappedInterner();
 
     _processPlugins();
 
     // Parse commandline options.
     CommandLineOptions options = CommandLineOptions.parse(args);
 
     // Cache options of interest to inform analysis.
     _setupEnv(options);
 
     // Do analysis.
     if (_isBatch) {
       _BatchRunner.runAsBatch(args, (List<String> args) {
         CommandLineOptions options = CommandLineOptions.parse(args);
         return _analyzeAll(options);
       });
     } else {
       ErrorSeverity severity = _analyzeAll(options);
       // In case of error propagate exit code.
       if (severity == ErrorSeverity.ERROR) {
         exitCode = severity.ordinal;
       }
     }
+
+    if (options.perfLog != null) {
+      _writePerfLog(options.perfLog, startTime);
+    }
   }
 
+  ErrorSeverity _analyzeAll(CommandLineOptions options) {
+    return _analyzeAllTag.makeCurrentWhile(() {
+      return _analyzeAllImpl(options);
+    });
+  }
+
+  static final PerformanceTag _analyzeAllTag =
+      new PerformanceTag("Driver._analyzeAll");
+
   /// Perform analysis according to the given [options].
-  ErrorSeverity _analyzeAll(CommandLineOptions options) {
+  ErrorSeverity _analyzeAllImpl(CommandLineOptions options) {
     if (!options.machineFormat) {
       outSink.writeln("Analyzing ${options.sourceFiles}...");
     }
 
     // Create a context, or re-use the previous one.
     try {
       _createAnalysisContext(options);
     } on _DriverError catch (error) {
       outSink.writeln(error.msg);
       return ErrorSeverity.ERROR;
@@ skipping 55 matching lines @@
         errorSink.writeln("${part.fullName} is a part and cannot be analyzed.");
         errorSink.writeln("Please pass in a library that contains this part.");
         exitCode = ErrorSeverity.ERROR.ordinal;
         allResult = allResult.max(ErrorSeverity.ERROR);
       }
     }
 
     return allResult;
   }
 
+  static _writePerfLog(String filename, int startTime) {
+    int totalTime = currentTimeMillis() - startTime;
+    int otherTime = totalTime;
+
+    // Convert performance tags to JSON representation.
+    var json = <String, dynamic>{};
+    for (PerformanceTag tag in PerformanceTag.all) {
+      if (tag != PerformanceTag.UNKNOWN) {
+        int tagTime = tag.elapsedMs;
+        json[tag.label] = tagTime;
+        otherTime -= tagTime;
+      }
+    }
+    json['other'] = otherTime;
+    json['total'] = totalTime;
+
+    // Pretty-print the JSON, one line per value for readability.
+    var buf = new StringBuffer();

[Paul Berry, 2015/12/16 15:11:26]

There's already library code available to pretty-print the JSON.  Just do this:

var encoded = new JsonEncoder.withIndent('  ').encode(json);

[skybrian, 2015/12/16 18:48:10]

Thanks!

+    buf.writeln("{");
+    var firstLine = true;
+    for (var key in json.keys) {
+      if (!firstLine) buf.writeln(",");

[Brian Wilkerson, 2015/12/16 15:08:43]

style nit: we always use blocks for 'if's.

+      var val = json[key];
+      buf.write('  "$key": ${JSON.encode(val)}');
+      firstLine = false;
+    }
+    buf.writeln("\n}");

[Brian Wilkerson, 2015/12/16 15:08:43]

nit: seems strange to have a newline explicitly in the string rather than

buf.writeln();
buf.writeln('}');

+
+    // Save to disk.
+    new File(filename).writeAsStringSync(buf.toString());
+  }
+
   /// Determine whether the context created during a previous call to
   /// [_analyzeAll] can be re-used in order to analyze using [options].
   bool _canContextBeReused(CommandLineOptions options) {
     // TODO(paulberry): add a command-line option that disables context re-use.
     if (_context == null) {
       return false;
     }
     if (options.packageRootPath != _previousOptions.packageRootPath) {
       return false;
     }
@@ skipping 432 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;
   }
 }