Duplicate output

[tchap]

The following demo program prints two matching log entries:

package main

import (
	"os"

	"github.com/blendle/zapdriver"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

func main() {
	consoleEncoder := zapcore.NewConsoleEncoder(zap.NewDevelopmentEncoderConfig())

	core := zapcore.NewTee(
		zapcore.NewCore(consoleEncoder, os.Stderr, zapcore.ErrorLevel),
		zapcore.NewCore(consoleEncoder, os.Stdout, zapcore.InfoLevel),
	)

	logger := zap.New(core, zap.AddCaller())

	logger = logger.WithOptions(zapdriver.WrapCore())
	defer logger.Sync()

	logger.Info("Starting...")
}

I am actually not sure this can be fixed or simply this is a limitation of Zap, but it seems to me that Check simply cannot work properly in this case without calling Check on the underlying core. Will investigate the issue further...

[tchap]

In other words, using return c.Core.Check(ent, ce) in Check fixes the issue, but that is not what you want, you want to register the wrapping core, right?

[tchap]

What obviously works is to add

func Wrap(c zapcore.Core) zapcore.Core {
	return &core{c, newLabels(), newLabels()}
}

and do

core := zapcore.NewTee(
	zapdriver.Wrap(zapcore.NewCore(consoleEncoder, os.Stderr, zapcore.ErrorLevel)),
	zapdriver.Wrap(zapcore.NewCore(consoleEncoder, os.Stdout, zapcore.InfoLevel)),
)

[tchap]

Ok, can be done already

core := zapcore.NewTee(
	zap.New(zapcore.NewCore(consoleEncoder, os.Stderr, zapcore.ErrorLevel)).
                WithOptions(zapdriver.WrapCore()).Core(),
	zap.New(zapcore.NewCore(consoleEncoder, os.Stdout, zapcore.InfoLevel)).
                WithOptions(zapdriver.WrapCore()).Core(),
)

Still wondering whether the library can be fixed so that the original code works. Not sure...