Fix EncodingError message in String#to_sym

Author: andrykonchin

spec/ruby/core/string/shared/to_sym.rb

@@ -67,6 +67,6 @@
     invalid_utf8.should_not.valid_encoding?
     -> {
       invalid_utf8.send(@method)
-    }.should raise_error(EncodingError, /invalid/)
+    }.should raise_error(EncodingError, 'invalid symbol in encoding UTF-8 :"\xC3"')
   end
 end

src/main/java/org/truffleruby/core/exception/CoreExceptions.java

@@ -1118,6 +1118,15 @@ public RubyException encodingError(String message, Node currentNode) {
         return ExceptionOperations.createRubyException(context, exceptionClass, errorMessage, currentNode, null);
     }
 
+    @TruffleBoundary
+    public RubyException encodingError(Object string, RubyEncoding encoding, Node currentNode) {
+        RubyClass exceptionClass = context.getCoreLibrary().encodingErrorClass;
+        String message = StringUtils.format("invalid symbol in encoding %s :%s", encoding, inspect(string));
+        RubyString errorMessage = StringOperations.createUTF8String(context, language, message);
+
+        return ExceptionOperations.createRubyException(context, exceptionClass, errorMessage, currentNode, null);
+    }
+
     @TruffleBoundary
     public RubyException encodingCompatibilityErrorIncompatible(RubyEncoding a, RubyEncoding b, Node currentNode) {
         return encodingCompatibilityError(

src/main/java/org/truffleruby/core/string/StringNodes.java

@@ -2618,7 +2618,7 @@ protected RubySymbol toSymBroken(Object string, boolean preserveSymbol,
                 @Cached RubyStringLibrary strings,
                 @Bind("strings.getTString(string)") AbstractTruffleString tstring,
                 @Bind("strings.getEncoding(string)") RubyEncoding encoding) {
-            throw new RaiseException(getContext(), coreExceptions().encodingError("invalid encoding symbol", this));
+            throw new RaiseException(getContext(), coreExceptions().encodingError(string, encoding, this));
         }
     }