Add negation to single-identifier tests in status files.

tools/testing/dart/status_file.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:io';
 
 import 'environment.dart';
 import 'expectation.dart';
 import 'path.dart';
 import 'status_expression.dart';
 
-/// Splits out a trailing line comment
-final _commentPattern = new RegExp("^([^#]*)(#.*)?\$");
-
 /// Matches the header that begins a new section, like:
 ///
 ///     [ $compiler == dart2js && $minified ]
-final _sectionPattern = new RegExp(r"^\[([^\]]+)\]");
+final _sectionPattern = new RegExp(r"^\[(.+?)\]");
 
 /// Matches an entry that defines the status for a path in the current section,
 /// like:
 ///
 ///     some/path/to/some_test: Pass || Fail
 final _entryPattern = new RegExp(r"\s*([^: ]*)\s*:(.*)");
 
 /// Matches an issue number in a comment, like:
 ///
 ///     blah_test: Fail # Issue 1234
 ///                       ^^^^
-final _issuePattern = new RegExp("[Ii]ssue ([0-9]+)");
+final _issuePattern = new RegExp(r"[Ii]ssue (\d+)");
 
 /// A parsed status file, which describes how a collection of tests are
 /// expected to behave under various configurations and conditions.
 ///
 /// Each status file is made of a series of sections. Each section begins with
 /// a header, followed by a series of entries. A header is enclosed in square
 /// brackets and contains a Boolean expression. That expression is evaluated in
 /// an environment. If it evaluates to true, then the entries after the header
 /// take effect.
 ///
@@ skipping 24 matching lines @@
 
         if (errors != null) {
           for (var error in errors) {
             print("- ${error.replaceAll('\n', '\n  ')}");
           }
         }
         exit(1);
       }
 
       // Strip off the comment and whitespace.
-      var match = _commentPattern.firstMatch(line);
-      var source = "";
+      var source = line;
       var comment = "";
-      if (match != null) {
-        source = match[1].trim();
-        comment = match[2] ?? "";
+      var hashIndex = line.indexOf('#');
+      if (hashIndex >= 0) {
+        source = line.substring(0, hashIndex);
+        comment = line.substring(hashIndex);
       }
+      source = source.trim();
 
       // Ignore empty (or comment-only) lines.
       if (source.isEmpty) continue;
 
       // See if we are starting a new section.
-      match = _sectionPattern.firstMatch(source);
+      var match = _sectionPattern.firstMatch(source);
       if (match != null) {
         try {
           var condition = Expression.parse(match[1].trim());
 
           var errors = <String>[];
           condition.validate(errors);
 
           if (errors.isNotEmpty) {
             var s = errors.length > 1 ? "s" : "";
             fail('Validation error$s', errors);
@@ skipping 45 matching lines @@
             .toFilePath(windows: Platform.operatingSystem == "windows"))
         .join(new Path("../../../../"));
     return new Path(_path).relativeTo(repoRoot).toString();
   }
 
   /// Returns the issue number embedded in [comment] or `null` if there is none.
   int _issueNumber(String comment) {
     var match = _issuePattern.firstMatch(comment);
     if (match == null) return null;
 
-    return int.parse(match[1], onError: (_) => null);
+    return int.parse(match[1]);
   }
 
   String toString() {
     var buffer = new StringBuffer();
     for (var section in sections) {
       buffer.writeln("[${section._condition}]");
 
       for (var entry in section.entries) {
         buffer.write("${entry.path}: ${entry.expectations.join(', ')}");
         if (entry.issue != null) buffer.write(" # Issue ${entry.issue}");
@@ skipping 27 matching lines @@
 }
 
 /// Describes the test status of the file or files at a given path.
 class StatusEntry {
   final String path;
   final List<Expectation> expectations;
   final int issue;
 
   StatusEntry(this.path, this.expectations, this.issue);
 }