Fix String#encode and convert fallback value into String with #to_str

Author: andrykonchin

CHANGELOG.md

@@ -38,6 +38,7 @@ Compatibility:
 * Fix `IO#{autoclose=,autoclose?}` and raise `IOError` when io is closed (@andrykonchin).
 * Fix `Thread#{thread_variable_get,thread_variable_set,thread_variable?,key?,[],[]=,fetch}` and convert a non-String/Symbol thread-local variable name to String using `#to_str` (@andrykonchin).
 * Fix formatting in `Exception#full_message` when `RuntimeError` is not handled and `highlight` option is specified (@andrykonchin).
+* Fix `String#encode` and convert fallback values into String using `#to_str` (@andrykonchin).
 
 Performance:
 

spec/tags/core/string/encode_tags.txt

@@ -1,30 +1,14 @@
-fails:String#encode given the fallback option given a hash calls to_str on the returned value
-fails:String#encode given the fallback option given a hash does not call to_s on the returned value
 fails:String#encode given the fallback option given a hash raises an error if the key is not present in the hash
 fails:String#encode given the fallback option given a hash raises an error if the value is itself invalid
 fails:String#encode given the fallback option given an object not responding to [] raises an error
-fails:String#encode given the fallback option given a proc calls to_str on the returned value
-fails:String#encode given the fallback option given a proc does not call to_s on the returned value
 fails:String#encode given the fallback option given a proc raises an error if the returned value is itself invalid
-fails:String#encode given the fallback option given a lambda calls to_str on the returned value
-fails:String#encode given the fallback option given a lambda does not call to_s on the returned value
 fails:String#encode given the fallback option given a lambda raises an error if the returned value is itself invalid
-fails:String#encode given the fallback option given a method calls to_str on the returned value
-fails:String#encode given the fallback option given a method does not call to_s on the returned value
 fails:String#encode given the fallback option given a method raises an error if the returned value is itself invalid
 fails:String#encode when passed options normalizes newlines with cr_newline option
 fails:String#encode when passed options normalizes newlines with crlf_newline option
-fails:String#encode! given the fallback option given a hash calls to_str on the returned value
-fails:String#encode! given the fallback option given a hash does not call to_s on the returned value
 fails:String#encode! given the fallback option given a hash raises an error if the key is not present in the hash
 fails:String#encode! given the fallback option given a hash raises an error if the value is itself invalid
 fails:String#encode! given the fallback option given an object not responding to [] raises an error
-fails:String#encode! given the fallback option given a proc calls to_str on the returned value
-fails:String#encode! given the fallback option given a proc does not call to_s on the returned value
 fails:String#encode! given the fallback option given a proc raises an error if the returned value is itself invalid
-fails:String#encode! given the fallback option given a lambda calls to_str on the returned value
-fails:String#encode! given the fallback option given a lambda does not call to_s on the returned value
 fails:String#encode! given the fallback option given a lambda raises an error if the returned value is itself invalid
-fails:String#encode! given the fallback option given a method calls to_str on the returned value
-fails:String#encode! given the fallback option given a method does not call to_s on the returned value
 fails:String#encode! given the fallback option given a method raises an error if the returned value is itself invalid

src/main/ruby/truffleruby/core/string.rb

@@ -419,6 +419,7 @@ def encode!(to = undefined, from = undefined, **options)
           (_, fallback_enc_from, fallback_enc_to, error_bytes, _) = ec.primitive_errinfo
           rep = fallback[error_bytes.force_encoding(fallback_enc_from)]
           raise ec.last_error unless rep
+          rep = Truffle::Type.rb_convert_type rep, String, :to_str
           dest << rep.encode(fallback_enc_to)
           status = ec.primitive_convert src, dest, nil, nil
         end