template.go: .section {@} won't output integers #1357
Description
by sam.irvine:
What steps will reproduce the problem?
import template "template"
import bytes "bytes"
type astruct struct {
intval []int
intval2 int
}
var testTemplate string =
`
{.repeated section intval}{@}{.alternates with},{.or}EMPTY!{.end}
{.section intval2}{@},{.or}EMPTY!{.end}
"{.section intval2}{@}{.end}"<- Quote should not be empty
`
func TestEmpty(t *testing.T) {
templ,err := template.Parse(testTemplate,nil)
if err != nil {
t.Errorf("Template parse error")
return
}
apply := astruct{intval: []int{10,20,30,40}, intval2: 10}
writeBuffer := bytes.NewBuffer(new([512]byte)[0:512])
_ = templ.Execute(apply,writeBuffer)
fmt.Printf("Template apply results: %s\n", writeBuffer.String())
}
What is the expected output?
Template apply results:
10,20,30,40
10
"10"<- Quote should not be empty
What do you see instead?
Template apply results:
10,20,30,40
EMPTY!
""<- Quote should not be empty
Which compiler are you using (5g, 6g, 8g, gccgo)?
6g
Which operating system are you using?
Linux 2.6.35.9-64.fc14.x86_64
Which revision are you using? (hg identify)
23006c94f1aa
Please provide any additional information below.
reflect.IntValue (and probably others) are missing from the type switch in
template/template.go: func empty(v reflect.Value) bool
This result defaults to true. This causes int types to be considered empty in some
cases and thus skipped in .section template evaluation. It does not happen all the time
but I didn't dig around long enough to figure out why. Adding a type switch case to
handle reflect.IntValue: return false resolved the issue for me.