Tidy up ErrorProcessor and AnalyzerConverter

Some of the parameters noted can be required and/or non-nullable as
per our internal usage, but this is all public API, so I'm just leaving
a note.

Mainly just simplify the implementation of ErrorProcessor.getProcessor.

Change-Id: Idebcf4a2485029c914d495cabfa3a1e98824c72c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/396360
Commit-Queue: Samuel Rawlins <[email protected]>
Reviewed-by: Konstantin Shcheglov <[email protected]>

Author: srawlins

pkg/analyzer/lib/source/error_processor.dart

@@ -5,6 +5,8 @@
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/task/options.dart';
+import 'package:collection/collection.dart';
+import 'package:meta/meta.dart';
 import 'package:yaml/yaml.dart';
 
 /// String identifiers mapped to associated severities.
@@ -77,31 +79,23 @@ class ErrorProcessor {
   ///
   /// Note: [code] is normalized to uppercase; `errorCode.name` for regular
   /// analysis issues uses uppercase; `errorCode.name` for lints uses lowercase.
+  @visibleForTesting
   bool appliesTo(AnalysisError error) =>
       code == error.errorCode.name ||
       code == error.errorCode.name.toUpperCase();
 
   @override
   String toString() => "ErrorProcessor[code='$code', severity=$severity]";
 
-  /// Return an error processor associated in the [analysisOptions] for the
+  /// Returns an error processor associated in the [analysisOptions] for the
   /// given [error], or `null` if none is found.
   static ErrorProcessor? getProcessor(
-      AnalysisOptions? analysisOptions, AnalysisError error) {
-    if (analysisOptions == null) {
-      return null;
-    }
-
-    // Let the user configure how specific errors are processed.
-    List<ErrorProcessor> processors = analysisOptions.errorProcessors;
-
-    // Add the strong mode processor.
-    processors = processors.toList();
-    for (var processor in processors) {
-      if (processor.appliesTo(error)) {
-        return processor;
-      }
-    }
-    return null;
+    // TODO(srawlins): Make `analysisOptions` non-nullable, in a breaking
+    // change release.
+    AnalysisOptions? analysisOptions,
+    AnalysisError error,
+  ) {
+    return analysisOptions?.errorProcessors
+        .firstWhereOrNull((processor) => processor.appliesTo(error));
   }
 }

pkg/analyzer_plugin/lib/utilities/analyzer_converter.dart

@@ -17,12 +17,17 @@ import 'package:analyzer_plugin/protocol/protocol_common.dart' as plugin;
 ///
 /// Clients may not extend, implement or mix-in this class.
 class AnalyzerConverter {
-  /// Convert the analysis [error] from the 'analyzer' package to an analysis
-  /// error defined by the plugin API. If a [lineInfo] is provided then the
-  /// error's location will have a start line and start column. If a [severity]
-  /// is provided, then it will override the severity defined by the error.
-  plugin.AnalysisError convertAnalysisError(analyzer.AnalysisError error,
-      {analyzer.LineInfo? lineInfo, analyzer.ErrorSeverity? severity}) {
+  /// Converts the analysis [error] from the 'analyzer' package to an analysis
+  /// error defined by the plugin API.
+  ///
+  /// If a [lineInfo] is provided then the error's location will have a start
+  /// line and start column. If a [severity] is provided, then it will override
+  /// the severity defined by the error.
+  plugin.AnalysisError convertAnalysisError(
+    analyzer.AnalysisError error, {
+    analyzer.LineInfo? lineInfo,
+    analyzer.ErrorSeverity? severity,
+  }) {
     var errorCode = error.errorCode;
     severity ??= errorCode.errorSeverity;
     var offset = error.offset;
@@ -58,15 +63,19 @@ class AnalyzerConverter {
         hasFix: true);
   }
 
-  /// Convert the list of analysis [errors] from the 'analyzer' package to a
-  /// list of analysis errors defined by the plugin API. If a [lineInfo] is
-  /// provided then the resulting errors locations will have a start line and
-  /// start column. If an analysis [options] is provided then the severities of
-  /// the errors will be altered based on those options.
+  /// Converts the list of analysis [errors] from the 'analyzer' package to a
+  /// list of analysis errors defined by the plugin API.
+  ///
+  /// The severities of the errors are altered based on [options].
   List<plugin.AnalysisError> convertAnalysisErrors(
-      List<analyzer.AnalysisError> errors,
-      {analyzer.LineInfo? lineInfo,
-      analyzer.AnalysisOptions? options}) {
+    List<analyzer.AnalysisError> errors, {
+    // TODO(srawlins): Make `lineInfo` required and non-nullable, in a breaking
+    // change release.
+    analyzer.LineInfo? lineInfo,
+    // TODO(srawlins): Make `options` required and non-nullable, in a breaking
+    // change release.
+    analyzer.AnalysisOptions? options,
+  }) {
     var serverErrors = <plugin.AnalysisError>[];
     for (var error in errors) {
       var processor = analyzer.ErrorProcessor.getProcessor(options, error);

pkg/analyzer_plugin/test/utilities/analyzer_converter_test.dart

@@ -141,8 +141,11 @@ class AnalyzerConverterTest extends AbstractSingleUnitTest {
     ];
     var lineInfo = analyzer.LineInfo([0, 10, 20]);
 
-    var pluginErrors =
-        converter.convertAnalysisErrors(analyzerErrors, lineInfo: lineInfo);
+    var pluginErrors = converter.convertAnalysisErrors(
+      analyzerErrors,
+      lineInfo: lineInfo,
+      options: analyzer.AnalysisOptionsImpl(),
+    );
     expect(pluginErrors, hasLength(analyzerErrors.length));
     assertError(pluginErrors[0], analyzerErrors[0],
         startColumn: 4, startLine: 2);
@@ -177,7 +180,10 @@ class AnalyzerConverterTest extends AbstractSingleUnitTest {
       await createError(25),
     ];
 
-    var pluginErrors = converter.convertAnalysisErrors(analyzerErrors);
+    var pluginErrors = converter.convertAnalysisErrors(
+      analyzerErrors,
+      options: analyzer.AnalysisOptionsImpl(),
+    );
     expect(pluginErrors, hasLength(analyzerErrors.length));
     assertError(pluginErrors[0], analyzerErrors[0]);
     assertError(pluginErrors[1], analyzerErrors[1]);