Make the exit code for dartanalyzer more deterministic.

pkg/analyzer_cli/lib/src/error_severity.dart

Index: pkg/analyzer_cli/lib/src/error_severity.dart
diff --git a/pkg/analyzer_cli/lib/src/error_severity.dart b/pkg/analyzer_cli/lib/src/error_severity.dart
index 17b7fe5f8867b2fe03de84f34d02eff92c06e333..4344bbaaa11142356866b1b150193839df270e83 100644
--- a/pkg/analyzer_cli/lib/src/error_severity.dart
+++ b/pkg/analyzer_cli/lib/src/error_severity.dart
@@ -6,51 +6,39 @@ import 'package:analyzer/error/error.dart';
 import 'package:analyzer/source/error_processor.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/engine.dart' hide AnalysisResult;
-import 'package:analyzer_cli/src/error_formatter.dart';
 import 'package:analyzer_cli/src/options.dart';
 
 /// Check various configuration options to get a desired severity for this
 /// [error] (or `null` if it's to be suppressed).
-ProcessedSeverity determineProcessedSeverity(AnalysisError error,
+ErrorSeverity determineProcessedSeverity(AnalysisError error,
     CommandLineOptions commandLineOptions, AnalysisOptions analysisOptions) {
-  ErrorSeverity severity = computeSeverity(error, commandLineOptions,
-      analysisOptions: analysisOptions);
-  bool isOverridden = false;
-
-  // Skip TODOs categorically (unless escalated to ERROR or HINT.)
-  // https://github.com/dart-lang/sdk/issues/26215
+  ErrorSeverity severity =
+      computeSeverity(error, commandLineOptions, analysisOptions);
+  // Skip TODOs categorically unless escalated to ERROR or HINT (#26215).
   if (error.errorCode.type == ErrorType.TODO &&
       severity == ErrorSeverity.INFO) {
     return null;
   }
 
-  // First check for a filter.
-  if (severity == null) {
-    // Null severity means the error has been explicitly ignored.
-    return null;
-  } else {
-    isOverridden = true;
-  }
-
+  // TODO(devoncarew): We should not filter hints here.
   // If not overridden, some "natural" severities get globally filtered.
-  if (!isOverridden) {
-    // Check for global hint filtering.
-    if (severity == ErrorSeverity.INFO && commandLineOptions.disableHints) {
-      return null;
-    }
+  // Check for global hint filtering.
+  if (severity == ErrorSeverity.INFO && commandLineOptions.disableHints) {
+    return null;
   }
 
-  return new ProcessedSeverity(severity, isOverridden);
+  return severity;
 }
 
 /// Compute the severity of the error; however:
 /// - if [options.enableTypeChecks] is false, then de-escalate checked-mode
 ///   compile time errors to a severity of [ErrorSeverity.INFO].
-/// - if [options.hintsAreFatal] is true, escalate hints to errors.
 /// - if [options.lintsAreFatal] is true, escalate lints to errors.
 ErrorSeverity computeSeverity(
-    AnalysisError error, CommandLineOptions commandLineOptions,
-    {AnalysisOptions analysisOptions}) {
+  AnalysisError error,
+  CommandLineOptions commandLineOptions,
+  AnalysisOptions analysisOptions,
+) {
   if (analysisOptions != null) {
     ErrorProcessor processor =
         ErrorProcessor.getProcessor(analysisOptions, error);
@@ -63,10 +51,9 @@ ErrorSeverity computeSeverity(
   if (!commandLineOptions.enableTypeChecks &&
       error.errorCode.type == ErrorType.CHECKED_MODE_COMPILE_TIME_ERROR) {
     return ErrorSeverity.INFO;
-  } else if (commandLineOptions.hintsAreFatal && error.errorCode is HintCode) {
-    return ErrorSeverity.ERROR;
   } else if (commandLineOptions.lintsAreFatal && error.errorCode is LintCode) {
     return ErrorSeverity.ERROR;
   }
+
   return error.errorCode.errorSeverity;
 }