Fix logrus verbosity level checker (#369)

* fix verbosity checker

* add test for verbosity checker

logging/logrus/grpclogger.go

@@ -21,5 +21,5 @@ type logrusGrpcLoggerV2 struct {
 }
 
 func (l *logrusGrpcLoggerV2) V(level int) bool {
-	return int(l.Level) >= level
+	return l.Logger.IsLevelEnabled(logrus.Level(level))
 }

logging/logrus/grpclogger_test.go

@@ -0,0 +1,71 @@
+package grpc_logrus
+
+import (
+	"testing"
+
+	"github.com/sirupsen/logrus"
+)
+
+func Test_logrusGrpcLoggerV2_V(t *testing.T) {
+	tests := []struct {
+		name       string
+		setupLevel logrus.Level
+		inLevel    logrus.Level
+		want       bool
+	}{
+		{
+			name:       "WarnLevel setup when we have WarnLevel msg should return TRUE",
+			setupLevel: logrus.WarnLevel,
+			inLevel:    logrus.WarnLevel,
+			want:       true,
+		},
+		{
+			name:       "WarnLevel setup when we have ErrorLevel msg should return TRUE",
+			setupLevel: logrus.WarnLevel,
+			inLevel:    logrus.ErrorLevel,
+			want:       true,
+		},
+		{
+			name:       "WarnLevel setup when we have InfoLevel msg should return FALSE",
+			setupLevel: logrus.WarnLevel,
+			inLevel:    logrus.InfoLevel,
+			want:       false,
+		},
+		{
+			name:       "WarnLevel setup when we have DebugLevel msg should return FALSE",
+			setupLevel: logrus.WarnLevel,
+			inLevel:    logrus.DebugLevel,
+			want:       false,
+		},
+		{
+			name:       "WarnLevel setup when we have TraceLevel msg should return FALSE",
+			setupLevel: logrus.WarnLevel,
+			inLevel:    logrus.TraceLevel,
+			want:       false,
+		},
+		{
+			name:       "TraceLevel setup when we have WarnLevel msg should return TRUE",
+			setupLevel: logrus.TraceLevel,
+			inLevel:    logrus.WarnLevel,
+			want:       true,
+		},
+		{
+			name:       "TraceLevel setup when we have TraceLevel msg should return TRUE",
+			setupLevel: logrus.TraceLevel,
+			inLevel:    logrus.TraceLevel,
+			want:       true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			lr := logrus.New()
+			lr.SetLevel(tt.setupLevel)
+
+			l := &logrusGrpcLoggerV2{logrus.NewEntry(lr)}
+
+			if got := l.V(int(tt.inLevel)); got != tt.want {
+				t.Errorf("V() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}