Add Logger values into Msg before handling and log values

logger-core.go

@@ -3,6 +3,7 @@ package log
 import (
 	"fmt"
 	"path/filepath"
+	"slices"
 )
 
 // loggerCore is the essential part of Logger.
@@ -24,7 +25,8 @@ func (l loggerCore) asLogger() Logger {
 
 // Returns a logger that adds the given values to logged messages.
 func (l loggerCore) WithValues(v ...interface{}) Logger {
-	l.values = append(l.values, v...)
+	l.assertNonZero()
+	l.values = append(slices.Clone(l.values), v...)
 	return l.asLogger()
 }
 
@@ -91,6 +93,7 @@ func (l loggerCore) lazyLog(level Level, skip int, f func() Msg) {
 	for i := len(l.msgMaps) - 1; i >= 0; i-- {
 		r = l.msgMaps[i](r)
 	}
+	r = r.WithValues(l.values...)
 	l.handle(level, r, names)
 }
 
@@ -102,9 +105,7 @@ func (l loggerCore) handle(level Level, m Msg, names []string) {
 		Level: level,
 		Names: names,
 	}
-	if !l.nonZero {
-		panic(fmt.Sprintf("Logger uninitialized. names=%q", l.names))
-	}
+	l.assertNonZero()
 	for _, h := range l.Handlers {
 		h.Handle(r)
 	}
@@ -123,3 +124,9 @@ func (l *loggerCore) SetHandlers(h ...Handler) {
 	l.Handlers = h
 	l.nonZero = true
 }
+
+func (l *loggerCore) assertNonZero() {
+	if !l.nonZero {
+		panic(fmt.Sprintf("Logger uninitialized. names=%q", l.names))
+	}
+}

stream-handler.go

@@ -1,6 +1,7 @@
 package log
 
 import (
+	"fmt"
 	"io"
 )
 
@@ -34,6 +35,15 @@ func twoLineFormatter(msg Record) []byte {
 	}
 	b = append(b, "]\n  "...)
 	b = append(b, msg.Text()...)
+	msg.Values(func(value interface{}) (more bool) {
+		b = append(b, ' ')
+		if item, ok := value.(item); ok {
+			b = fmt.Appendf(b, "%s=%s", item.key, item.value)
+		} else {
+			b = fmt.Append(b, value)
+		}
+		return true
+	})
 	if b[len(b)-1] != '\n' {
 		b = append(b, '\n')
 	}