Add --build-summary-only-diet option.

pkg/analyzer_cli/lib/src/options.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.options;
 
 import 'dart:io';
 
 import 'package:analyzer_cli/src/driver.dart';
 import 'package:args/args.dart';
@@ skipping 27 matching lines @@
 
   /// Whether to use build mode.
   final bool buildMode;
 
   /// List of summary file paths to use in build mode.
   final List<String> buildSummaryInputs;
 
   /// Whether to skip analysis when creating summaries in build mode.
   final bool buildSummaryOnly;
 
+  /// Whether to use diet parsing, i.e. skip function bodies. We don't need to
+  /// analyze function bodies to use summaries during future compilation steps.
+  final bool buildSummaryOnlyDiet;
+
   /// The path to output the summary when creating summaries in build mode.
   final String buildSummaryOutput;
 
   /// Whether to suppress a nonzero exit code in build mode.
   final bool buildSuppressExitCode;
 
   /// The path to the dart SDK
   String dartSdkPath;
 
   /// A table mapping the names of defined variables to their values.
@@ skipping 68 matching lines @@
   /// Whether to use strong static checking.
   final bool strongMode;
 
   /// Initialize options from the given parsed [args].
   CommandLineOptions._fromArgs(
       ArgResults args, Map<String, String> definedVariables)
       : buildAnalysisOutput = args['build-analysis-output'],
         buildMode = args['build-mode'],
         buildSummaryInputs = args['build-summary-input'],
         buildSummaryOnly = args['build-summary-only'],
+        buildSummaryOnlyDiet = args['build-summary-only-diet'],
         buildSummaryOutput = args['build-summary-output'],
         buildSuppressExitCode = args['build-suppress-exit-code'],
         dartSdkPath = args['dart-sdk'],
         definedVariables = definedVariables,
         analysisOptionsFile = args['options'],
         disableHints = args['no-hints'],
         displayVersion = args['version'],
         enableConditionalDirectives = args['enable-conditional-directives'],
         enableNullAwareOperators = args['enable-null-aware-operators'],
         enableStrictCallChecks = args['enable-strict-call-checks'],
@@ skipping 56 matching lines @@
       }
     }
 
     // OK.  Report deprecated options.
     if (options.enableNullAwareOperators) {
       errorSink.writeln(
           "Info: Option '--enable-null-aware-operators' is no longer needed. "
           "Null aware operators are supported by default.");
     }
 
+    // Build mode.
+    if (options.buildSummaryOnlyDiet && !options.buildSummaryOnly) {
+      printAndFail('The option --build-summary-only-diet can be used only '
+          'together with --build-summary-only.');
+    }
+
     return options;
   }
 
   static String _getVersion() {
     try {
       // This is relative to bin/snapshot, so ../..
       String versionPath =
           Platform.script.resolve('../../version').toFilePath();
       File versionFile = new File(versionPath);
       return versionFile.readAsStringSync().trim();
@@ skipping 101 matching lines @@
           hide: true)
       ..addOption('build-summary-output',
           help: 'Specifies the path to the file where the summary information '
               'should be written.',
           hide: true)
       ..addFlag('build-summary-only',
           help: 'Disable analysis (only generate summaries).',
           defaultsTo: false,
           negatable: false,
           hide: true)
+      ..addFlag('build-summary-only-diet',
+          help: 'Diet parse function bodies.',
+          defaultsTo: false,
+          negatable: false,
+          hide: true)
       ..addFlag('build-suppress-exit-code',
           help: 'Exit with code 0 even if errors are found.',
           defaultsTo: false,
           negatable: false,
           hide: true)
       //
       // Hidden flags.
       //
       ..addFlag('enable-async',
           help: 'Enable support for the proposed async feature.',
@@ skipping 227 matching lines @@
 
   int _getNextFlagIndex(args, i) {
     for (; i < args.length; ++i) {
       if (args[i].startsWith('--')) {
         return i;
       }
     }
     return i;
   }
 }