Fix IncreaseLevel being reset after With

increase_level_test.go

@@ -29,10 +29,13 @@ import (
 	"go.uber.org/zap/zaptest/observer"
 )
 
-func newLoggedEntry(level zapcore.Level, msg string) observer.LoggedEntry {
+func newLoggedEntry(level zapcore.Level, msg string, fields ...zapcore.Field) observer.LoggedEntry {
+	if len(fields) == 0 {
+		fields = []zapcore.Field{}
+	}
 	return observer.LoggedEntry{
 		Entry:   zapcore.Entry{Level: level, Message: msg},
-		Context: []zapcore.Field{},
+		Context: fields,
 	}
 }
 
@@ -75,9 +78,15 @@ func TestIncreaseLevel(t *testing.T) {
 		errorLogger.Warn("ignored warn log")
 		errorLogger.Error("increase level error log")
 
+		withFields := errorLogger.With(String("k", "v"))
+		withFields.Debug("ignored debug log with fields")
+		withFields.Warn("ignored warn log with fields")
+		withFields.Error("increase level error log with fields")
+
 		assert.Equal(t, []observer.LoggedEntry{
 			newLoggedEntry(WarnLevel, "original warn log"),
 			newLoggedEntry(ErrorLevel, "increase level error log"),
+			newLoggedEntry(ErrorLevel, "increase level error log with fields", String("k", "v")),
 		}, logs.AllUntimed(), "unexpected logs")
 
 		assert.Empty(t, errorOut.String(), "expect no error output")

zapcore/increase_level.go

@@ -23,8 +23,7 @@ package zapcore
 import "fmt"
 
 type levelFilterCore struct {
-	Core
-
+	core  Core
 	level LevelEnabler
 }
 
@@ -46,10 +45,22 @@ func (c *levelFilterCore) Enabled(lvl Level) bool {
 	return c.level.Enabled(lvl)
 }
 
+func (c *levelFilterCore) With(fields []Field) Core {
+	return &levelFilterCore{c.core.With(fields), c.level}
+}
+
 func (c *levelFilterCore) Check(ent Entry, ce *CheckedEntry) *CheckedEntry {
 	if !c.Enabled(ent.Level) {
 		return ce
 	}
 
-	return c.Core.Check(ent, ce)
+	return c.core.Check(ent, ce)
+}
+
+func (c *levelFilterCore) Write(ent Entry, fields []Field) error {
+	return c.core.Write(ent, fields)
+}
+
+func (c *levelFilterCore) Sync() error {
+	return c.core.Sync()
 }

zapcore/increase_level_test.go

@@ -26,6 +26,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
 	. "go.uber.org/zap/zapcore"
 	"go.uber.org/zap/zaptest/observer"
 )
@@ -35,6 +36,7 @@ func TestIncreaseLevel(t *testing.T) {
 		coreLevel     Level
 		increaseLevel Level
 		wantErr       bool
+		with          []Field
 	}{
 		{
 			coreLevel:     InfoLevel,
@@ -49,6 +51,11 @@ func TestIncreaseLevel(t *testing.T) {
 			coreLevel:     InfoLevel,
 			increaseLevel: ErrorLevel,
 		},
+		{
+			coreLevel:     InfoLevel,
+			increaseLevel: ErrorLevel,
+			with:          []Field{zap.String("k", "v")},
+		},
 		{
 			coreLevel:     ErrorLevel,
 			increaseLevel: DebugLevel,
@@ -82,6 +89,10 @@ func TestIncreaseLevel(t *testing.T) {
 				return
 			}
 
+			if len(tt.with) > 0 {
+				filteredLogger = filteredLogger.With(tt.with)
+			}
+
 			require.NoError(t, err)
 
 			for l := DebugLevel; l <= FatalLevel; l++ {