Report messages instead of just printing.

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

Index: pkg/front_end/lib/src/fasta/deprecated_problems.dart
diff --git a/pkg/front_end/lib/src/fasta/deprecated_problems.dart b/pkg/front_end/lib/src/fasta/deprecated_problems.dart
index 90897d9eeae9ec76da1194649b12facc80bcceed..6c6fad3be63bf3b3203d08941950c75d300c55a8 100644
--- a/pkg/front_end/lib/src/fasta/deprecated_problems.dart
+++ b/pkg/front_end/lib/src/fasta/deprecated_problems.dart
@@ -11,9 +11,11 @@ import 'dart:convert' show JSON;
 import 'dart:io'
     show ContentType, HttpClient, HttpClientRequest, SocketException, stderr;
 
-import 'colors.dart' show red;
+import 'command_line_reporting.dart' show isFatal;
 
-import 'messages.dart' show errorsAreFatal, deprecated_format, isVerbose;
+import 'messages.dart' show LocatedMessage, isVerbose, templateUnspecified;
+
+import 'severity.dart' show Severity;
 
 const String defaultServerAddress = "http://127.0.0.1:59410/";
 
@@ -36,34 +38,12 @@ Uri firstSourceUri;
 /// handled correctly, the user will never see a stack trace that says "user
 /// error".
 dynamic deprecated_inputError(Uri uri, int charOffset, Object error) {
-  if (errorsAreFatal && isVerbose) {
+  if (isFatal(Severity.error) && isVerbose) {
     print(StackTrace.current);

[Siggi Cherem (dart-lang), 2017/07/13 21:05:56]

do we still need this here? 

I expect this will be printed by however handles the exception

[ahe, 2017/07/14 10:01:07]

Using --fatal=errors will stop compilation immediately after the first error.

If you also use --verbose, the current stack trace will be printed. This is a
useful technique for fixing incorrect errors.

Unfortunately, I've frequently found bugs in how the VM preserves stack traces
across throws and rethrows, as well as when there's an asynchronous gap. Since
the point at line 41 is as close as it gets to the actual location I want to
find when I use --fatal=errors and --verbose, I like to keep it here.

In addition, by printing the stack trace here, I don't have to worry about it
getting printed multiple times as it sometimes did in dart2js. Also, it doesn't
confuse crash reporting as it also sometimes does in dart2js.

   }
   throw new deprecated_InputError(uri, charOffset, error);
 }
 
-String deprecated_printUnexpected(Uri uri, int charOffset, String message) {
-  String formattedMessage =
-      deprecated_formatUnexpected(uri, charOffset, message);
-  if (errorsAreFatal) {
-    print(formattedMessage);
-    if (isVerbose) print(StackTrace.current);
-    throw new deprecated_InputError(uri, charOffset, message);
-  }
-  print(formattedMessage);
-  return formattedMessage;
-}
-
-String deprecated_formatUnexpected(Uri uri, int charOffset, String message) {
-  return deprecated_format(uri, charOffset, colorError("Error: $message"));
-}
-
-String colorError(String message) {
-  // TODO(ahe): Colors need to be optional. Doesn't work well in Emacs or on
-  // Windows.
-  return red(message);
-}
-
 class deprecated_InputError {
   final Uri uri;
 
@@ -76,8 +56,16 @@ class deprecated_InputError {
 
   toString() => "deprecated_InputError: $error";
 
-  String deprecated_format() =>
-      deprecated_formatUnexpected(uri, charOffset, safeToString(error));
+  /// Converts [error] to a [LocatedMessage] using [templateUnspecified]. Using
+  /// [templateUnspecified] is deprecated behavior.
+  ///
+  /// Static method to discourage use and requiring call-sites to include the
+  /// text `deprecated_`.
+  static LocatedMessage toMessage(deprecated_InputError error) {
+    return templateUnspecified
+        .withArguments(safeToString(error.error))
+        .withLocation(error.uri, error.charOffset);
+  }
 }
 
 class Crash {