chore: add tests (#3921)

core/breaker/googlebreaker.go

@@ -1,7 +1,6 @@
 package breaker
 
 import (
-	"math"
 	"time"
 
 	"github.com/zeromicro/go-zero/core/collection"
@@ -38,7 +37,8 @@ func (b *googleBreaker) accept() error {
 	accepts, total := b.history()
 	weightedAccepts := b.k * float64(accepts)
 	// https://landing.google.com/sre/sre-book/chapters/handling-overload/#eq2101
-	dropRatio := math.Max(0, (float64(total-protection)-weightedAccepts)/float64(total+1))
+	// for better performance, no need to care about negative ratio
+	dropRatio := (float64(total-protection) - weightedAccepts) / float64(total+1)
 	if dropRatio <= 0 {
 		return nil
 	}

zrpc/internal/serverinterceptors/breakerinterceptor_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/zeromicro/go-zero/core/breaker"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
@@ -27,3 +28,12 @@ func TestUnaryBreakerInterceptor(t *testing.T) {
 	})
 	assert.NotNil(t, err)
 }
+
+func TestUnaryBreakerInterceptor_Unavailable(t *testing.T) {
+	_, err := UnaryBreakerInterceptor(context.Background(), nil, &grpc.UnaryServerInfo{
+		FullMethod: "any",
+	}, func(_ context.Context, _ any) (any, error) {
+		return nil, breaker.ErrServiceUnavailable
+	})
+	assert.NotNil(t, err)
+}