Fixed prefixFieldClashes for TextFormatter and added coverage

formatter.go

@@ -34,15 +34,18 @@ func prefixFieldClashes(data Fields, fieldMap FieldMap) {
 	timeKey := fieldMap.resolve(FieldKeyTime)
 	if t, ok := data[timeKey]; ok {
 		data["fields."+timeKey] = t
+		delete(data, timeKey)
 	}
 
 	msgKey := fieldMap.resolve(FieldKeyMsg)
 	if m, ok := data[msgKey]; ok {
 		data["fields."+msgKey] = m
+		delete(data, msgKey)
 	}
 
 	levelKey := fieldMap.resolve(FieldKeyLevel)
 	if l, ok := data[levelKey]; ok {
 		data["fields."+levelKey] = l
+		delete(data, levelKey)
 	}
 }

text_formatter.go

@@ -51,7 +51,6 @@ type TextFormatter struct {
 	// be desired.
 	DisableSorting bool
 
-
 	// Disables the truncation of the level text to 4 characters.
 	DisableLevelTruncation bool
 
@@ -81,7 +80,8 @@ func (f *TextFormatter) init(entry *Entry) {
 
 // Format renders a single log entry
 func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
-	var b *bytes.Buffer
+	prefixFieldClashes(entry.Data, f.FieldMap)
+
 	keys := make([]string, 0, len(entry.Data))
 	for k := range entry.Data {
 		keys = append(keys, k)
@@ -90,14 +90,14 @@ func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
 	if !f.DisableSorting {
 		sort.Strings(keys)
 	}
+
+	var b *bytes.Buffer
 	if entry.Buffer != nil {
 		b = entry.Buffer
 	} else {
 		b = &bytes.Buffer{}
 	}
 
-	prefixFieldClashes(entry.Data, emptyFieldMap)
-
 	f.Do(func() { f.init(entry) })
 
 	isColored := (f.ForceColors || f.isTerminal) && !f.DisableColors

text_formatter_test.go

@@ -191,6 +191,12 @@ func TestTextFormatterFieldMap(t *testing.T) {
 		Message: "oh hi",
 		Level:   WarnLevel,
 		Time:    time.Date(1981, time.February, 24, 4, 28, 3, 100, time.UTC),
+		Data: Fields{
+			"field1":     "f1",
+			"message":    "messagefield",
+			"somelevel":  "levelfield",
+			"timeywimey": "timeywimeyfield",
+		},
 	}
 
 	b, err := formatter.Format(entry)
@@ -199,7 +205,13 @@ func TestTextFormatterFieldMap(t *testing.T) {
 	}
 
 	assert.Equal(t,
-		`timeywimey="1981-02-24T04:28:03Z" somelevel=warning message="oh hi"`+"\n",
+		`timeywimey="1981-02-24T04:28:03Z" `+
+			`somelevel=warning `+
+			`message="oh hi" `+
+			`field1=f1 `+
+			`fields.message=messagefield `+
+			`fields.somelevel=levelfield `+
+			`fields.timeywimey=timeywimeyfield`+"\n",
 		string(b),
 		"Formatted doesn't respect correct FieldMap")
 }