Merge pull request #18 from ssgreg/feature/with-level

add: WithLevel to stack additional level checker

README.md

@@ -3,7 +3,7 @@
 [![GoDoc](https://godoc.org/github.com/ssgreg/logf?status.svg)](https://godoc.org/github.com/ssgreg/logf)
 [![Build Status](https://github.com/ssgreg/logf/actions/workflows/go.yml/badge.svg)](https://github.com/ssgreg/logf/actions/workflows/go.yml)
 [![Go Report Status](https://goreportcard.com/badge/github.com/ssgreg/logf)](https://goreportcard.com/report/github.com/ssgreg/logf)
-[![Coverage Status](https://coveralls.io/repos/github/ssgreg/logf/badge.svg?branch=master&service=github)](https://coveralls.io/github/ssgreg/logf?branch=master)
+[![Coverage Status](https://codecov.io/gh/ssgreg/logf/branch/master/graph/badge.svg)](https://codecov.io/gh/ssgreg/logf)
 
 Faster-than-light, asynchronous, structured logger in Go with zero allocation count.
 

level.go

@@ -12,7 +12,7 @@ type Level int8
 const (
 	// LevelError allows to log errors only.
 	LevelError Level = iota
-	// LevelWarning allows to log errors and warnings.
+	// LevelWarn allows to log errors and warnings.
 	LevelWarn
 	// LevelInfo is the default logging level. Allows to log errors, warnings and infos.
 	LevelInfo

logger.go

@@ -63,10 +63,20 @@ func (l *Logger) AtLevel(lvl Level, fn func(LogFunc)) {
 	})
 }
 
+// WithLevel returns a new logger with the given additional level checker.
+func (l *Logger) WithLevel(level LevelChecker) *Logger {
+	cc := l.clone()
+	cc.level = func(lvl Level) bool {
+		return level(lvl) && l.level(lvl)
+	}
+
+	return cc
+}
+
 // WithName returns a new Logger adding the given name to the calling one.
 // Name separator is a period.
 //
-// Loggers has no name by default.
+// Loggers have no name by default.
 func (l *Logger) WithName(n string) *Logger {
 	if n == "" {
 		return l

logger_test.go

@@ -76,6 +76,23 @@ func TestLoggerName(t *testing.T) {
 	assert.Equal(t, "1.2", w.Entry.LoggerName)
 }
 
+func TestLoggerWithLevel(t *testing.T) {
+	w := &testEntryWriter{}
+
+	// Set a name for the logger.
+	logger := NewLogger(LevelInfo, w).WithLevel(
+		func(lvl Level) bool {
+			return lvl == LevelError
+		},
+	)
+
+	logger.Info("")
+	assert.Nil(t, w.Entry)
+
+	logger.Error("")
+	assert.NotNil(t, w.Entry)
+}
+
 func TestLoggerAtLevel(t *testing.T) {
 	w := &testEntryWriter{}
 	logger := NewLogger(LevelError, w)