Error reporting for spans.

pkg/analyzer/test/generated/all_the_rest_test.dart

Index: pkg/analyzer/test/generated/all_the_rest_test.dart
diff --git a/pkg/analyzer/test/generated/all_the_rest_test.dart b/pkg/analyzer/test/generated/all_the_rest_test.dart
index 25c34650ac60a763244c2b619fa664f213b8480a..9dd08e8ee4c3f6060abf4e720228dbb2c642e480 100644
--- a/pkg/analyzer/test/generated/all_the_rest_test.dart
+++ b/pkg/analyzer/test/generated/all_the_rest_test.dart
@@ -30,6 +30,7 @@ import 'package:analyzer/src/generated/utilities_collection.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:path/path.dart';
+import 'package:source_span/source_span.dart';
 import 'package:unittest/unittest.dart';
 
 import '../reflective_tests.dart';
@@ -7334,6 +7335,27 @@ class ErrorReporterTest extends EngineTestCase {
     expect(error.offset, element.nameOffset);
   }
 
+  void test_reportErrorForSpan() {
+    GatheringErrorListener listener = new GatheringErrorListener();
+    ErrorReporter reporter = new ErrorReporter(listener, new TestSource());
+
+    var src = '''
+foo: bar
+zap: baz
+''';
+
+    int offset = src.indexOf('baz');
+    int length = 'baz'.length;
+
+    SourceSpan span = new SourceFile(src).span(offset, offset + length);
+
+    reporter.reportErrorForSpan(
+        AnalysisOptionsWarningCode.UNSUPPORTED_OPTION, span, ['test', 'zap']);
+    expect(listener.errors, hasLength(1));
+    expect(listener.errors.first.offset, offset);
+    expect(listener.errors.first.length, length);
+  }
+
   void test_reportTypeErrorForNode_differentNames() {
     DartType firstType = createType("/test1.dart", "A");
     DartType secondType = createType("/test2.dart", "B");