[THRIFT-4195] Compilation to GO produces broken code

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Invalid
• Affects Version/s: 0.10.0
• Fix Version/s: 0.11.0
• Component/s: Go - Compiler

Environment

MacOS 10.12.4 (16E195)
go version go1.8.1 darwin/amd64

• Assignee: Unassigned
• Reporter: Stanislav Baranov
• Created: 10/May/17 14:00
• Updated: 14/Dec/17 13:55
• Resolved: 13/May/17 19:29

Description

Sample source file (see attached sample.thrift):

namespace go reports

typedef string ReportState
const ReportState ReportStateQueued = "QUEUED";
const ReportState ReportStateCalculating = "CALCULATING";
const ReportState ReportStateImporting = "IMPORTING";
const ReportState ReportStateFinished = "FINISHED";
const ReportState ReportStateFailed = "FAILED";

struct ReportFilter {
    1: i64 quantity,
    2: i64 dataVersion,
    3: string subscriptionID,
    4: optional string principalID,
    5: optional string createdOn,
    6: optional list<ReportState> states,
}

after compilation as:

thrift -r -v -o ./ -out ./go --gen go:package_prefix="git.4tree.de/" ./sample.thrift

Produces code (see attached sample.go) which contains:

func (p *ReportFilter)  ReadField6(iprot thrift.TProtocol) error {
  _, size, err := iprot.ReadListBegin()
  if err != nil {
    return thrift.PrependError("error reading list begin: ", err)
  }
  tSlice := make([]ReportState, 0, size)
  p.States =  tSlice
  for i := 0; i < size; i ++ {
var _elem0 string
    if v, err := iprot.ReadString(); err != nil {
    return thrift.PrependError("error reading field 0: ", err)
} else {
    _elem0 = v
}
    p.States = append(p.States, _elem0)
  }
  if err := iprot.ReadListEnd(); err != nil {
    return thrift.PrependError("error reading list end: ", err)
  }
  return nil
}

When trying to compile this code, GO triggers an error:

cannot use _elem0 (type string) as type ReportState in append

at line:

 p.States = append(p.States, _elem0)

This code compiles normal using thrift 0.9.3

Issue Links

• duplicates: THRIFT-4173 Go: thrift compiler generates wrong code for list of aliased type