Grand test fixup (#138)

* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig

vendor/github.com/tmthrgd/go-hex/hex_amd64.go

@@ -0,0 +1,94 @@
+// Copyright 2016 Tom Thorogood. All rights reserved.
+// Use of this source code is governed by a
+// Modified BSD License license that can be found in
+// the LICENSE file.
+
+// +build amd64,!gccgo,!appengine
+
+package hex
+
+import "golang.org/x/sys/cpu"
+
+// RawEncode encodes src into EncodedLen(len(src))
+// bytes of dst.  As a convenience, it returns the number
+// of bytes written to dst, but this value is always EncodedLen(len(src)).
+// RawEncode implements hexadecimal encoding for a given alphabet.
+func RawEncode(dst, src, alpha []byte) int {
+	if len(alpha) != 16 {
+		panic("invalid alphabet")
+	}
+
+	if len(dst) < len(src)*2 {
+		panic("dst buffer is too small")
+	}
+
+	if len(src) == 0 {
+		return 0
+	}
+
+	switch {
+	case cpu.X86.HasAVX:
+		encodeAVX(&dst[0], &src[0], uint64(len(src)), &alpha[0])
+	case cpu.X86.HasSSE41:
+		encodeSSE(&dst[0], &src[0], uint64(len(src)), &alpha[0])
+	default:
+		encodeGeneric(dst, src, alpha)
+	}
+
+	return len(src) * 2
+}
+
+// Decode decodes src into DecodedLen(len(src)) bytes, returning the actual
+// number of bytes written to dst.
+//
+// If Decode encounters invalid input, it returns an error describing the failure.
+func Decode(dst, src []byte) (int, error) {
+	if len(src)%2 != 0 {
+		return 0, errLength
+	}
+
+	if len(dst) < len(src)/2 {
+		panic("dst buffer is too small")
+	}
+
+	if len(src) == 0 {
+		return 0, nil
+	}
+
+	var (
+		n  uint64
+		ok bool
+	)
+	switch {
+	case cpu.X86.HasAVX:
+		n, ok = decodeAVX(&dst[0], &src[0], uint64(len(src)))
+	case cpu.X86.HasSSE41:
+		n, ok = decodeSSE(&dst[0], &src[0], uint64(len(src)))
+	default:
+		n, ok = decodeGeneric(dst, src)
+	}
+
+	if !ok {
+		return 0, InvalidByteError(src[n])
+	}
+
+	return len(src) / 2, nil
+}
+
+//go:generate go run asm_gen.go
+
+// This function is implemented in hex_encode_amd64.s
+//go:noescape
+func encodeAVX(dst *byte, src *byte, len uint64, alpha *byte)
+
+// This function is implemented in hex_encode_amd64.s
+//go:noescape
+func encodeSSE(dst *byte, src *byte, len uint64, alpha *byte)
+
+// This function is implemented in hex_decode_amd64.s
+//go:noescape
+func decodeAVX(dst *byte, src *byte, len uint64) (n uint64, ok bool)
+
+// This function is implemented in hex_decode_amd64.s
+//go:noescape
+func decodeSSE(dst *byte, src *byte, len uint64) (n uint64, ok bool)