feat: new method--HIncrByFloat(#136)

structure/hash.go

@@ -494,3 +494,64 @@ func (hs *HashStructure) HIncrBy(key, field []byte, increment int64) (int64, err
 
 	return val, nil
 }
+
+// HIncrByFloat increments the float value of a hash field by the given number.
+func (hs *HashStructure) HIncrByFloat(key, field []byte, increment float64) (float64, error) {
+	// Check the parameters
+	if len(key) == 0 || len(field) == 0 {
+		return 0, _const.ErrKeyIsEmpty
+	}
+
+	// Find the hash metadata by the given key
+	hashMeta, err := hs.findHashMeta(key, Hash)
+	if err != nil {
+		return 0, err
+	}
+
+	// If the counter is 0, return 0
+	if hashMeta.counter == 0 {
+		return 0, nil
+	}
+
+	// Create a new HashField
+	hf := &HashField{
+		field:   field,
+		key:     key,
+		version: hashMeta.version,
+	}
+
+	// Encode the HashField
+	hfBuf := hf.encodeHashField()
+
+	// Get the field from the database
+	value, err := hs.db.Get(hfBuf)
+	if err != nil && err == _const.ErrKeyNotFound {
+		return 0, nil
+	}
+
+	// Convert the value to float64
+	val, err := strconv.ParseFloat(string(value), 64)
+	if err != nil {
+		return 0, err
+	}
+
+	// Add the increment to the value
+	val += increment
+
+	// Convert the value to string
+	value = []byte(strconv.FormatFloat(val, 'f', -1, 64))
+
+	// new a write batch
+	batch := hs.db.NewWriteBatch(config.DefaultWriteBatchOptions)
+
+	// Put the field to the database
+	_ = batch.Put(hfBuf, value)
+
+	// Commit the write batch
+	err = batch.Commit()
+	if err != nil {
+		return 0, err
+	}
+
+	return val, nil
+}

structure/hash_test.go

@@ -175,3 +175,36 @@ func TestHashStructure_HIncrBy(t *testing.T) {
 	assert.Equal(t, v4, int64(0))
 
 }
+
+func TestHashStructure_HIncrByFloat(t *testing.T) {
+	hash := initHashDB()
+
+	ok1, err := hash.HSet(randkv.GetTestKey(1), []byte("field1"), []byte("10"))
+	assert.Nil(t, err)
+	assert.True(t, ok1)
+
+	ok2, err := hash.HSet(randkv.GetTestKey(1), []byte("field2"), []byte("10"))
+	assert.Nil(t, err)
+	assert.True(t, ok2)
+
+	ok3, err := hash.HSet(randkv.GetTestKey(1), []byte("field3"), []byte("10"))
+	assert.Nil(t, err)
+	assert.True(t, ok3)
+
+	v1, err := hash.HIncrByFloat(randkv.GetTestKey(1), []byte("field1"), 1.1)
+	assert.Nil(t, err)
+	assert.Equal(t, v1, float64(11.1))
+
+	v2, err := hash.HIncrByFloat(randkv.GetTestKey(1), []byte("field2"), -1.1)
+	assert.Nil(t, err)
+	assert.Equal(t, v2, float64(8.9))
+
+	v3, err := hash.HIncrByFloat(randkv.GetTestKey(1), []byte("field3"), 0)
+	assert.Nil(t, err)
+	assert.Equal(t, v3, float64(10))
+
+	v4, err := hash.HIncrByFloat(randkv.GetTestKey(1), []byte("field4"), 1.1)
+	assert.Nil(t, err)
+	assert.Equal(t, v4, float64(0))
+
+}