Refactor code for checking that generated files are up to date.

pkg/analyzer/lib/src/codegen/tools.dart

 // Copyright (c) 2014, 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.
 
 /**
  * Tools for generating code in analyzer and analysis server.
  */
 library analyzer.src.codegen.tools;
 
 import 'dart:io';
@@ skipping 268 matching lines @@
    * Replace the [output] with the correct contents.  [pkgPath] is the path to
    * the current package.
    */
   void generate(String pkgPath);
 
   /**
    * Get a [FileSystemEntity] representing the output file or directory.
    * [pkgPath] is the path to the current package.
    */
   FileSystemEntity output(String pkgPath);
+
+  /**
+   * Check that all of the [targets] are up to date.  If they are not, print
+   * out a message instructing the user to regenerate them, and exit with a
+   * nonzero error code.
+   *
+   * [pkgPath] is the path to the current package.  [generatorRelPath] is the
+   * path to a .dart script the user may use to regenerate the targets.
+   *
+   * To avoid mistakes when run on Windows, [generatorRelPath] always uses
+   * POSIX directory separators.
+   */
+  static void checkAll(String pkgPath, String generatorRelPath,
+      Iterable<GeneratedContent> targets) {
+    bool generateNeeded = false;
+    for (GeneratedContent target in targets) {
+      if (!target.check(pkgPath)) {
+        print(
+            '${target.output(pkgPath).absolute} does not have expected contents.');
+        generateNeeded = true;
+      }
+    }
+    if (generateNeeded) {
+      print('Please regenerate using:');
+      String executable = Platform.executable;
+      String packageRoot = '';
+      if (Platform.packageRoot.isNotEmpty) {
+        packageRoot = ' --package-root=${Platform.packageRoot}';
+      }
+      String generateScript =
+          join(pkgPath, joinAll(posix.split(generatorRelPath)));
+      print('  $executable$packageRoot $generateScript');
+      exit(1);
+    } else {
+      print('All generated files up to date.');
+    }
+  }
+
+  /**
+   * Regenerate all of the [targets].  [pkgPath] is the path to the current
+   * package.
+   */
+  static void generateAll(String pkgPath, Iterable<GeneratedContent> targets) {
+    for (GeneratedContent target in targets) {
+      target.generate(pkgPath);
+    }
+  }
 }
 
 /**
  * Class representing a single output directory (either generated code or
  * generated HTML). No other content should exist in the directory.
  */
 class GeneratedDirectory extends GeneratedContent {
   /**
    * The path to the directory that will have the generated content.
    */
@@ skipping 252 matching lines @@
     if (lines.last.isEmpty) {
       lines.removeLast();
       buffer.add(new dom.Text(lines.join('\n$indent') + '\n'));
       indentNeeded = true;
     } else {
       buffer.add(new dom.Text(lines.join('\n$indent')));
       indentNeeded = false;
     }
   }
 }