strings.Split crashes on empty string, empty split

[bytbox]

What steps will reproduce the problem?
1. strings.Split(line, "", -1)
2. compile
3. run

What is the expected output?
It should return an empty array.

What do you see instead?
Crash:
panic PC=0x2b75b4c5e228
runtime.panic+0x7c /usr/local/src/i9/src/pkg/runtime/proc.c:1012
        runtime.panic(0x2b7500000000, 0x405eaa)
panicstring+0x60 /usr/local/src/i9/src/pkg/runtime/runtime.c:83
        panicstring(0x464758, 0x2b75b4c7c1e0)
runtime.panicindex+0x1c /usr/local/src/i9/src/pkg/runtime/runtime.c:44
        runtime.panicindex()
strings.explode+0x145 /usr/local/src/i9/src/pkg/strings/strings.go:32
        strings.explode(0x43e408, 0x0, 0x0, 0x43e408, 0x0, ...)
strings.genSplit+0x4f /usr/local/src/i9/src/pkg/strings/strings.go:145
        strings.genSplit(0x43e408, 0x0, 0x0, 0x6, 0x0, ...)
strings.Split+0x43 /usr/local/src/i9/src/pkg/strings/strings.go:173
        strings.Split(0x43e408, 0x0, 0x43e408, 0x0, 0xffffffff00000000, ...)
etc...


What is your $GOOS?  $GOARCH?
$ echo $GOOS and $GOARCH
linux and amd64


Which revision are you using?  (hg identify)
b69ec24ad6dc+ tip

[bytbox]

Comment 1:

correction - strings.Split(line, "", -1) should read strings.Split("", "", -1).

[rsc]

Comment 2:

Nice.

Owner changed to [email protected].

Status changed to Accepted.

[rsc]

Comment 3:

Status changed to HelpWanted.

[gopherbot]

Comment 4 by jan.hosang:

Analogously
strings.Split("", "a", -1)
should be an empty array as well?
Currently the result is [""].

[rsc]

Comment 5:

Re #4: No, the only way to get an empty array is to pass a max of zero (kind of useless).
Split(",,", ",", -1) = []string{"", "", ""}
Split(",", ",", -1) = []string{"", ""}
Split("", ",", -1) = []string{""}

[gopherbot]

Comment 6 by jan.hosang:

But
Split("", "", -1) = []string{}
? (Just to make sure.)
When I fix this, should I include a test for these cases anywhere?

[rsc]

Comment 7:

> Split("", "", -1) = []string{}
It does appear that way.  That's a bit odd, but consistent with the other "" separators,
because
Split("ab", "", -1) = []string{"a", "b"}
NOT Split("ab", "", -1) = []string{"", "a", "b", ""}

[bytbox]

Comment 8:

Potentially, someone might use Split(str, "", -1) to loop through all characters in a
string (that's pretty much the only use for it, I think) - in which case len(Split(str,
"", -1)) had better be the same as len(str).

[robpike]

Comment 9:

This issue was closed by revision 0cd8777.

Status changed to Fixed.