Add some length/offset tests where offset < length.
diff --git a/snappy_test.go b/snappy_test.go
index a6fbbf0..c365e9c 100644
--- a/snappy_test.go
+++ b/snappy_test.go
@@ -198,6 +198,16 @@
"abcdabcd",
nil,
}, {
+ `decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=2; valid input`,
+ "\x08" + "\x0cabcd" + "\x01\x02",
+ "abcdcdcd",
+ nil,
+ }, {
+ `decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=1; valid input`,
+ "\x08" + "\x0cabcd" + "\x01\x01",
+ "abcddddd",
+ nil,
+ }, {
`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=0; zero offset`,
"\x08" + "\x0cabcd" + "\x01\x00",
"",
