package retry import ( "errors" "fmt" "testing" "github.com/stretchr/testify/assert" ) func TestSizer(t *testing.T) { tooLong := errors.New("too long") src := [][]byte{ []byte("foobarbaz"), []byte("gondwandaland"), []byte("longer and longer still, not quite done"), []byte("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua."), } // mimic a complex-ish data copy call bcopy := func(src []byte, size int) ([]byte, error) { if size < len(src) { return nil, tooLong } dst := make([]byte, size) copy(dst, src) return dst, nil } for i, b := range src { t.Run(fmt.Sprintf("bcopy_%d", i), func(t *testing.T) { var out []byte var err error WithSizes(1, 4096, func(size int) Hint { out, err = bcopy(b, size) return DoubleSize.If(err == tooLong) }) assert.Nil(t, err) assert.Equal(t, b, out[:len(b)]) }) } for i, b := range src { t.Run(fmt.Sprintf("bcopy_hint_%d", i), func(t *testing.T) { var tries int var err error var out []byte WithSizes(1, 4096, func(size int) Hint { tries++ out, err = bcopy(b, size) return Size(len(b)).If(err == tooLong) }) assert.Nil(t, err) assert.Equal(t, b, out) assert.Equal(t, 2, tries) }) } t.Run("exceedsMax", func(t *testing.T) { var tries int var err error WithSizes(1, 1024, func(_ int) Hint { tries++ err = errors.New("foo") return DoubleSize }) assert.Error(t, err) assert.Equal(t, 11, tries) }) t.Run("hintExceedsMax", func(t *testing.T) { var tries int var lastSize int WithSizes(1, 1024, func(size int) Hint { tries++ lastSize = size return Size(1025) }) assert.Equal(t, 1024, lastSize) assert.Equal(t, 2, tries) }) t.Run("weirdSizeAndMax", func(t *testing.T) { var tries int var lastSize int WithSizes(3, 1022, func(size int) Hint { tries++ lastSize = size return DoubleSize }) assert.Equal(t, 10, tries) assert.Equal(t, 1022, lastSize) }) t.Run("sizeExceedsMax", func(t *testing.T) { var lastSize int WithSizes(1023, 1022, func(size int) Hint { lastSize = size return DoubleSize }) assert.Equal(t, 0, lastSize) }) }