Added methods to detect whether the log level is enabled.

log.go

@@ -54,6 +54,31 @@ type Log interface {
 	// WithStack adds call stack information to the current log.
 	WithStack() Log
 
+	// IsLevelEnabled checks whether the given log level is enabled.
+	// Always returns false if the given log level is invalid.
+	IsLevelEnabled(Level) bool
+
+	// IsPanicLevelEnabled checks whether the PanicLevel is enabled.
+	IsPanicLevelEnabled() bool
+
+	// IsFatalLevelEnabled checks whether the FatalLevel is enabled.
+	IsFatalLevelEnabled() bool
+
+	// IsErrorLevelEnabled checks whether the ErrorLevel is enabled.
+	IsErrorLevelEnabled() bool
+
+	// IsWarnLevelEnabled checks whether the WarnLevel is enabled.
+	IsWarnLevelEnabled() bool
+
+	// IsInfoLevelEnabled checks whether the InfoLevel is enabled.
+	IsInfoLevelEnabled() bool
+
+	// IsDebugLevelEnabled checks whether the DebugLevel is enabled.
+	IsDebugLevelEnabled() bool
+
+	// IsTraceLevelEnabled checks whether the TraceLevel is enabled.
+	IsTraceLevelEnabled() bool
+
 	// Log uses the given parameters to record a log of the specified level.
 	// If the given log level is PanicLevel, the given panic function will be
 	// called automatically after logging is completed.
@@ -425,6 +450,47 @@ func (o *log) getCaller(level Level) string {
 	return internal.GetCaller(o.caller.Skip())
 }
 
+// IsLevelEnabled checks whether the given log level is enabled.
+// Always returns false if the given log level is invalid.
+func (o *log) IsLevelEnabled(level Level) bool {
+	return Level(atomic.LoadUint32(&o.core.level)).IsEnabled(level)
+}
+
+// IsPanicLevelEnabled checks whether the PanicLevel is enabled.
+func (o *log) IsPanicLevelEnabled() bool {
+	return o.IsLevelEnabled(PanicLevel)
+}
+
+// IsFatalLevelEnabled checks whether the FatalLevel is enabled.
+func (o *log) IsFatalLevelEnabled() bool {
+	return o.IsLevelEnabled(FatalLevel)
+}
+
+// IsErrorLevelEnabled checks whether the ErrorLevel is enabled.
+func (o *log) IsErrorLevelEnabled() bool {
+	return o.IsLevelEnabled(ErrorLevel)
+}
+
+// IsWarnLevelEnabled checks whether the WarnLevel is enabled.
+func (o *log) IsWarnLevelEnabled() bool {
+	return o.IsLevelEnabled(WarnLevel)
+}
+
+// IsInfoLevelEnabled checks whether the InfoLevel is enabled.
+func (o *log) IsInfoLevelEnabled() bool {
+	return o.IsLevelEnabled(InfoLevel)
+}
+
+// IsDebugLevelEnabled checks whether the DebugLevel is enabled.
+func (o *log) IsDebugLevelEnabled() bool {
+	return o.IsLevelEnabled(DebugLevel)
+}
+
+// IsTraceLevelEnabled checks whether the TraceLevel is enabled.
+func (o *log) IsTraceLevelEnabled() bool {
+	return o.IsLevelEnabled(TraceLevel)
+}
+
 // Log uses the given parameters to record a log of the specified level.
 // If the given log level is PanicLevel, the given panic function will be
 // called automatically after logging is completed.

logger_test.go

@@ -724,3 +724,92 @@ func TestLogger_AsStandardLogger(t *testing.T) {
 		t.Fatalf("Logger.AsStandardLogger(): got %q, want %q", got, want)
 	}
 }
+
+func TestLogger_IsLevelEnabled(t *testing.T) {
+	o := New("test")
+	o.SetLevel(TraceLevel)
+
+	items := []struct {
+		Given Level
+		Want  bool
+	}{
+		{TraceLevel, true},
+		{DebugLevel, true},
+		{InfoLevel, true},
+		{WarnLevel, true},
+		{ErrorLevel, true},
+		{FatalLevel, true},
+		{PanicLevel, true},
+		{Level(0), false},
+		{Level(10000), false},
+	}
+	for _, item := range items {
+		if got := o.IsLevelEnabled(item.Given); got != item.Want {
+			t.Fatalf("Logger.IsLevelEnabled(): got %v, want %v", got, item.Want)
+		}
+	}
+	if !o.IsPanicLevelEnabled() {
+		t.Fatal("Logger.IsPanicLevelEnabled(): got false, want true")
+	}
+	if !o.IsFatalLevelEnabled() {
+		t.Fatal("Logger.IsFatalLevelEnabled(): got false, want true")
+	}
+	if !o.IsErrorLevelEnabled() {
+		t.Fatal("Logger.IsErrorLevelEnabled(): got false, want true")
+	}
+	if !o.IsWarnLevelEnabled() {
+		t.Fatal("Logger.IsWarnLevelEnabled(): got false, want true")
+	}
+	if !o.IsInfoLevelEnabled() {
+		t.Fatal("Logger.IsInfoLevelEnabled(): got false, want true")
+	}
+	if !o.IsDebugLevelEnabled() {
+		t.Fatal("Logger.IsDebugLevelEnabled(): got false, want true")
+	}
+	if !o.IsTraceLevelEnabled() {
+		t.Fatal("Logger.IsTraceLevelEnabled(): got false, want true")
+	}
+
+	o.SetLevel(InfoLevel)
+
+	items = []struct {
+		Given Level
+		Want  bool
+	}{
+		{TraceLevel, false},
+		{DebugLevel, false},
+		{InfoLevel, true},
+		{WarnLevel, true},
+		{ErrorLevel, true},
+		{FatalLevel, true},
+		{PanicLevel, true},
+		{Level(0), false},
+		{Level(10000), false},
+	}
+	for _, item := range items {
+		if got := o.IsLevelEnabled(item.Given); got != item.Want {
+			t.Fatalf("Logger.IsLevelEnabled(): got %v, want %v", got, item.Want)
+		}
+	}
+	if !o.IsPanicLevelEnabled() {
+		t.Fatal("Logger.IsPanicLevelEnabled(): got false, want true")
+	}
+	if !o.IsFatalLevelEnabled() {
+		t.Fatal("Logger.IsFatalLevelEnabled(): got false, want true")
+	}
+	if !o.IsErrorLevelEnabled() {
+		t.Fatal("Logger.IsErrorLevelEnabled(): got false, want true")
+	}
+	if !o.IsWarnLevelEnabled() {
+		t.Fatal("Logger.IsWarnLevelEnabled(): got false, want true")
+	}
+	if !o.IsInfoLevelEnabled() {
+		t.Fatal("Logger.IsInfoLevelEnabled(): got false, want true")
+	}
+	if o.IsDebugLevelEnabled() {
+		t.Fatal("Logger.IsDebugLevelEnabled(): got true, want false")
+	}
+	if o.IsTraceLevelEnabled() {
+		t.Fatal("Logger.IsTraceLevelEnabled(): got true, want false")
+	}
+}