Server custom error severity support (#24452).

pkg/analysis_server/lib/src/protocol_server.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.
 
 library protocol.server;
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/plugin/protocol/protocol_dart.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart'
     as engine;
+import 'package:analyzer/source/error_processor.dart';
 import 'package:analyzer/src/generated/ast.dart' as engine;
 import 'package:analyzer/src/generated/element.dart' as engine;
 import 'package:analyzer/src/generated/engine.dart' as engine;
 import 'package:analyzer/src/generated/error.dart' as engine;
 import 'package:analyzer/src/generated/source.dart' as engine;
 import 'package:analyzer/src/generated/utilities_dart.dart' as engine;
 
 export 'package:analysis_server/plugin/protocol/protocol.dart';
 export 'package:analysis_server/plugin/protocol/protocol_dart.dart';
 
 /**
- * Returns a list of AnalysisErrors correponding to the given list of Engine
+ * Returns a list of AnalysisErrors corresponding to the given list of Engine
  * errors.
  */
 List<AnalysisError> doAnalysisError_listFromEngine(
-    engine.LineInfo lineInfo, List<engine.AnalysisError> errors) {
-  return errors.map((engine.AnalysisError error) {
-    return newAnalysisError_fromEngine(lineInfo, error);
-  }).toList();
+    engine.AnalysisContext context,
+    engine.LineInfo lineInfo,
+    List<engine.AnalysisError> errors) {
+  List<AnalysisError> serverErrors = <AnalysisError>[];
+  for (engine.AnalysisError error in errors) {
+    ErrorProcessor processor = ErrorProcessor.getProcessor(context, error);
+    if (processor != null) {
+      engine.ErrorSeverity severity = processor.severity;
+      // Errors with null severity are filtered out.
+      if (severity != null) {
+        // Specified severities override.
+        serverErrors
+            .add(newAnalysisError_fromEngine(lineInfo, error, severity));
+      }
+    } else {
+      serverErrors.add(newAnalysisError_fromEngine(lineInfo, error));
+    }
+  }
+  return serverErrors;
 }
 
 /**
  * Adds [edit] to the [FileEdit] for the given [element].
  */
 void doSourceChange_addElementEdit(
     SourceChange change, engine.Element element, SourceEdit edit) {
   engine.AnalysisContext context = element.context;
   engine.Source source = element.source;
   doSourceChange_addSourceEdit(change, context, source, edit);
@@ skipping 21 matching lines @@
     return type != null ? type.displayName : 'dynamic';
   } else if (element is engine.FunctionTypeAliasElement) {
     return element.returnType.toString();
   } else {
     return null;
   }
 }
 
 /**
  * Construct based on error information from the analyzer engine.
+ *
+ * If an [errorSeverity] is specified, it will override the one in [error].
  */
 AnalysisError newAnalysisError_fromEngine(
-    engine.LineInfo lineInfo, engine.AnalysisError error) {
+    engine.LineInfo lineInfo, engine.AnalysisError error,
+    [engine.ErrorSeverity errorSeverity]) {
   engine.ErrorCode errorCode = error.errorCode;
   // prepare location
   Location location;
   {
     String file = error.source.fullName;
     int offset = error.offset;
     int length = error.length;
     int startLine = -1;
     int startColumn = -1;
     if (lineInfo != null) {
       engine.LineInfo_Location lineLocation = lineInfo.getLocation(offset);
       if (lineLocation != null) {
         startLine = lineLocation.lineNumber;
         startColumn = lineLocation.columnNumber;
       }
     }
     location = new Location(file, offset, length, startLine, startColumn);
   }
+
+  // Deafult to the error's severity if none is specified.
+  errorSeverity ??= errorCode.errorSeverity;
+
   // done
-  var severity = new AnalysisErrorSeverity(errorCode.errorSeverity.name);
+  var severity = new AnalysisErrorSeverity(errorSeverity.name);
   var type = new AnalysisErrorType(errorCode.type.name);
   String message = error.message;
   String correction = error.correction;
   bool fix = hasFix(error.errorCode);
   return new AnalysisError(severity, type, location, message,
       correction: correction, hasFix: fix);
 }
 
 /**
  * Create a Location based on an [engine.Element].
@@ skipping 127 matching lines @@
     if (lineInfo != null) {
       engine.LineInfo_Location offsetLocation =
           lineInfo.getLocation(range.offset);
       startLine = offsetLocation.lineNumber;
       startColumn = offsetLocation.columnNumber;
     }
   }
   return new Location(
       source.fullName, range.offset, range.length, startLine, startColumn);
 }