Test failed in salsa20

[xiegeo]

go test -v github.com/davidlazar/go-crypto/salsa20 failed

FAIL: TestRandom (0.01s) panic: salsa20: output smaller than input

=== RUN   TestSalsa20
--- PASS: TestSalsa20 (0.11s)
=== RUN   TestXSalsa20
--- PASS: TestXSalsa20 (0.00s)
=== RUN   TestRandom
--- FAIL: TestRandom (0.01s)
panic: salsa20: output smaller than input [recovered]
        panic: salsa20: output smaller than input

goroutine 21 [running]:
testing.tRunner.func1(0xc0000bc300)
        c:/go/src/testing/testing.go:830 +0x6a4
panic(0x5d5ce0, 0x638e10)
        c:/go/src/runtime/panic.go:522 +0x1c3
golang.org/x/crypto/salsa20.XORKeyStream(0x7721d0, 0x0, 0x0, 0xc0000602e4, 0x2, 0x2, 0xc000060208, 0x8, 0x8, 0xc00005e240)
        C:/Users/xiege/go/pkg/mod/golang.org/x/crypto@v0.0.0-20190911031432-227b76d455e7/salsa20/salsa20.go:36 +0x2ea
github.com/davidlazar/go-crypto/salsa20.TestRandom(0xc0000bc300)
        C:/Users/xiege/go/pkg/mod/github.com/davidlazar/go-crypto@v0.0.0-20190522120613-62389b5e4ae0/salsa20/salsa20_test.go:40 +0x511
testing.tRunner(0xc0000bc300, 0x6165a0)
        c:/go/src/testing/testing.go:865 +0x16b
created by testing.(*T).Run
        c:/go/src/testing/testing.go:916 +0x662
FAIL    github.com/davidlazar/go-crypto/salsa20 0.651s

Using version go-crypto@v0.0.0-20190522120613-62389b5e4ae0,
golang.org/x/crypto@v0.0.0-20190911031432-227b76d455e7,
and go version go1.12.9 windows/amd64

[davidlazar]

Fixed; thanks.