Updates to the stress test

pkg/analysis_server/test/stress/utilities/server.dart

Index: pkg/analysis_server/test/stress/utilities/server.dart
diff --git a/pkg/analysis_server/test/stress/utilities/server.dart b/pkg/analysis_server/test/stress/utilities/server.dart
index 149dcdf7b7bbb9ae224f933637fe7f3b3051858d..ee52fdd6551ecd7369699b19ed6de443218225d6 100644
--- a/pkg/analysis_server/test/stress/utilities/server.dart
+++ b/pkg/analysis_server/test/stress/utilities/server.dart
@@ -17,6 +17,48 @@ import '../../integration/integration_test_methods.dart';
 import '../../integration/integration_tests.dart' as base;
 
 /**
+ * ???
+ */
+class ErrorMap {
+  /**
+   * A table mapping file paths to the errors associated with that file.
+   */
+  final Map<String, List<AnalysisError>> pathMap =
+      new HashMap<String, List<AnalysisError>>();
+
+  /**
+   * Initialize a newly created error map.
+   */
+  ErrorMap();
+
+  /**
+   * Initialize a newly created error map to contain the same mapping as the
+   * given [errorMap].
+   */
+  ErrorMap.from(ErrorMap errorMap) {
+    pathMap.addAll(errorMap.pathMap);
+  }
+
+  void operator []=(String filePath, List<AnalysisError> errors) {
+    pathMap[filePath] = errors;
+  }
+
+  /**
+   * Compare the this error map with the state captured in the given [errorMap].
+   * Throw an exception if the two maps do not agree.
+   */
+  String expectErrorMap(ErrorMap errorMap) {
+    StringBuffer buffer = new StringBuffer();
+    _ErrorComparator comparator = new _ErrorComparator(buffer);
+    comparator.compare(pathMap, errorMap.pathMap);
+    if (buffer.length > 0) {
+      return buffer.toString();
+    }
+    return null;
+  }
+}
+
+/**
  * An interface for starting and communicating with an analysis server running
  * in a separate process.
  */
@@ -27,11 +69,10 @@ class Server extends base.Server with IntegrationTestMixin {
   List<String> filesWithOverlays = <String>[];
 
   /**
-   * A table mapping the absolute paths of files to the most recent set of
-   * errors received for that file.
+   * A mapping from the absolute paths of files to the most recent set of errors
+   * received for that file.
    */
-  Map<String, List<AnalysisError>> _errorMap =
-      new HashMap<String, List<AnalysisError>>();
+  ErrorMap _errorMap = new ErrorMap();
 
   /**
    * Initialize a new analysis server. The analysis server is not running and
@@ -43,17 +84,41 @@ class Server extends base.Server with IntegrationTestMixin {
   }
 
   /**
+   * Return a list of the paths of files that are currently being analyzed.
+   */
+  List<String> get analyzedDartFiles {
+    // TODO(brianwilkerson) Implement this.
+    return <String>[];
+  }
+
+  /**
    * Return a table mapping the absolute paths of files to the most recent set
    * of errors received for that file. The content of the map will not change
    * when new sets of errors are received.
    */
-  Map<String, List<AnalysisError>> get errorMap =>
-      new HashMap<String, List<AnalysisError>>.from(_errorMap);
+  ErrorMap get errorMap => new ErrorMap.from(_errorMap);
 
   @override
   base.Server get server => this;
 
   /**
+   * Compute a mapping from each of the file paths in the given list of
+   * [filePaths] to the list of errors in the file at that path.
+   */
+  Future<ErrorMap> computeErrorMap(List<String> filePaths) async {
+    ErrorMap errorMap = new ErrorMap();
+    List<Future> futures = <Future>[];
+    for (String filePath in filePaths) {
+      futures.add(sendAnalysisGetErrors(filePath)
+          .then((AnalysisGetErrorsResult result) {
+        errorMap[filePath] = result.errors;
+      }));
+    }
+    await Future.wait(futures);
+    return errorMap;
+  }
+
+  /**
    * Remove any existing overlays.
    */
   Future<AnalysisUpdateContentResult> removeAllOverlays() {
@@ -84,3 +149,141 @@ class Server extends base.Server with IntegrationTestMixin {
     _errorMap[params.file] = params.errors;
   }
 }
+
+/**
+ * A utility class used to compare two sets of errors.
+ */
+class _ErrorComparator {
+  /**
+   * An empty list of analysis errors.
+   */
+  static final List<AnalysisError> NO_ERRORS = <AnalysisError>[];
+
+  /**
+   * The buffer to which an error description will be written if any of the
+   * files have different errors than are expected.
+   */
+  final StringBuffer buffer;
+
+  /**
+   * Initialize a newly created comparator to write to the given [buffer].
+   */
+  _ErrorComparator(this.buffer);
+
+  /**
+   * Compare the [actualErrorMap] and the [expectedErrorMap], writing a
+   * description to the [buffer] if they are not the same. The error maps are
+   * expected to be maps from absolute file paths to the list of actual or
+   * expected errors.
+   */
+  void compare(Map<String, List<AnalysisError>> actualErrorMap,
+      Map<String, List<AnalysisError>> expectedErrorMap) {
+    Set<String> allFiles = new HashSet();
+    allFiles.addAll(actualErrorMap.keys);
+    allFiles.addAll(expectedErrorMap.keys);
+    List<String> sortedFiles = allFiles.toList()..sort();
+    for (String filePath in sortedFiles) {
+      List<AnalysisError> actualErrors = actualErrorMap[filePath];
+      List<AnalysisError> expectedErrors = expectedErrorMap[filePath];
+      _compareLists(
+          filePath, actualErrors ?? NO_ERRORS, expectedErrors ?? NO_ERRORS);
+    }
+  }
+
+  /**
+   * Compare the [actualErrors] and [expectedErrors], writing a description to
+   * the [buffer] if they are not the same.
+   */
+  void _compareLists(String filePath, List<AnalysisError> actualErrors,
+      List<AnalysisError> expectedErrors) {
+    List<AnalysisError> remainingExpected =
+        new List<AnalysisError>.from(expectedErrors);
+    for (AnalysisError actualError in actualErrors) {
+      AnalysisError expectedError = _findError(remainingExpected, actualError);
+      if (expectedError == null) {
+        _writeReport(filePath, actualErrors, expectedErrors);
+        return;
+      }
+      remainingExpected.remove(expectedError);
+    }
+    if (remainingExpected.isNotEmpty) {
+      _writeReport(filePath, actualErrors, expectedErrors);
+    }
+  }
+
+  /**
+   * Return `true` if the [firstError] and the [secondError] are equivalent.
+   */
+  bool _equalErrors(AnalysisError firstError, AnalysisError secondError) =>
+      firstError.severity == secondError.severity &&
+      firstError.type == secondError.type &&
+      _equalLocations(firstError.location, secondError.location) &&
+      firstError.message == secondError.message;
+
+  /**
+   * Return `true` if the [firstLocation] and the [secondLocation] are
+   * equivalent.
+   */
+  bool _equalLocations(Location firstLocation, Location secondLocation) =>
+      firstLocation.file == secondLocation.file &&
+      firstLocation.offset == secondLocation.offset &&
+      firstLocation.length == secondLocation.length;
+
+  /**
+   * Search through the given list of [errors] for an error that is equal to the
+   * [targetError]. If one is found, return it, otherwise return `null`.
+   */
+  AnalysisError _findError(
+      List<AnalysisError> errors, AnalysisError targetError) {
+    for (AnalysisError error in errors) {
+      if (_equalErrors(error, targetError)) {
+        return error;
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Write the given list of [errors], preceded by a header beginning with the
+   * given [prefix].
+   */
+  void _writeErrors(String prefix, List<AnalysisError> errors) {
+    buffer.write(prefix);
+    buffer.write(errors.length);
+    buffer.write(' errors:');
+    for (AnalysisError error in errors) {
+      buffer.writeln();
+      Location location = error.location;
+      int offset = location.offset;
+      buffer.write('    ');
+      buffer.write(location.file);
+      buffer.write(' (');
+      buffer.write(offset);
+      buffer.write('..');
+      buffer.write(offset + location.length);
+      buffer.write(') ');
+      buffer.write(error.severity);
+      buffer.write(', ');
+      buffer.write(error.type);
+      buffer.write(' : ');
+      buffer.write(error.message);
+    }
+  }
+
+  /**
+   * Write a report of the differences between the [actualErrors] and the
+   * [expectedErrors]. The errors are reported as being from the file at the
+   * given [filePath].
+   */
+  void _writeReport(String filePath, List<AnalysisError> actualErrors,
+      List<AnalysisError> expectedErrors) {
+    if (buffer.length > 0) {
+      buffer.writeln();
+      buffer.writeln();
+    }
+    buffer.writeln(filePath);
+    _writeErrors('  Expected ', expectedErrors);
+    buffer.writeln();
+    _writeErrors('  Found ', expectedErrors);
+  }
+}