Report messages instead of just printing.

pkg/front_end/lib/src/fasta/messages.dart

 // Copyright (c) 2016, 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 fasta.messages;
 
-import 'dart:io' show exitCode;
-
 import 'package:kernel/ast.dart' show Library, Location, Program, TreeNode;
 
 import 'util/relativize.dart' show relativizeUri;
 
 import 'compiler_context.dart' show CompilerContext;
 
-import 'deprecated_problems.dart' show deprecated_InputError;
+import 'fasta_codes.dart' show Message;
 
-import 'colors.dart' show cyan, magenta;
-
-import 'fasta_codes.dart' show Message;
+import 'severity.dart' show Severity;
 
 export 'fasta_codes.dart';
 
-const bool hideWarnings = false;
-
-bool get errorsAreFatal => CompilerContext.current.options.errorsAreFatal;
-
-bool get nitsAreFatal => CompilerContext.current.options.nitsAreFatal;
-
-bool get warningsAreFatal => CompilerContext.current.options.warningsAreFatal;
-
 bool get isVerbose => CompilerContext.current.options.verbose;
 
-bool get hideNits => !isVerbose;
-
-bool get setExitCodeOnProblem {
-  return CompilerContext.current.options.setExitCodeOnProblem;
-}
-
 void warning(Message message, int charOffset, Uri uri) {
-  if (hideWarnings) return;
-  print(deprecated_format(
-      uri, charOffset, colorWarning("Warning: ${message.message}")));
-  if (warningsAreFatal) {
-    if (isVerbose) print(StackTrace.current);
-    throw new deprecated_InputError(
-        uri, charOffset, "Compilation aborted due to fatal warnings.");
-  }
+  CompilerContext.current
+      .report(message.withLocation(uri, charOffset), Severity.warning);
 }
 
 void nit(Message message, int charOffset, Uri uri) {
-  if (hideNits) return;
-  print(
-      deprecated_format(uri, charOffset, colorNit("Nit: ${message.message}")));
-  if (nitsAreFatal) {
-    if (isVerbose) print(StackTrace.current);
-    throw new deprecated_InputError(
-        uri, charOffset, "Compilation aborted due to fatal nits.");
-  }
-}
-
-String colorWarning(String message) {
-  // TODO(ahe): Colors need to be optional. Doesn't work well in Emacs or on
-  // Windows.
-  return magenta(message);
-}
-
-String colorNit(String message) {
-  // TODO(ahe): Colors need to be optional. Doesn't work well in Emacs or on
-  // Windows.
-  return cyan(message);
-}
-
-String deprecated_format(Uri uri, int charOffset, String message) {
-  if (setExitCodeOnProblem) {
-    exitCode = 1;
-  }
-  if (uri != null) {
-    String path = relativizeUri(uri);
-    Location location = charOffset == -1 ? null : getLocation(path, charOffset);
-    String sourceLine = getSourceLine(location);
-    if (sourceLine == null) {
-      sourceLine = "";
-    } else {
-      sourceLine = "\n$sourceLine\n"
-          "${' ' * (location.column - 1)}^";
-    }
-    String position = location?.toString() ?? path;
-    return "$position: $message$sourceLine";
-  } else {
-    return message;
-  }
+  CompilerContext.current
+      .report(message.withLocation(uri, charOffset), Severity.nit);
 }
 
 Location getLocation(String path, int charOffset) {
   return CompilerContext.current.uriToSource[path]
       ?.getLocation(path, charOffset);
 }
 
 Location getLocationFromUri(Uri uri, int charOffset) {
   if (charOffset == -1) return null;
   String path = relativizeUri(uri);
@@ skipping 21 matching lines @@
       program.libraries.clear();
       parent.parent = null;
       return result;
     } else {
       return null;
     }
   } else {
     return node.location;
   }
 }