x/tools/cmd/eg: does not support variadic functions

[mrwonko]

What version of Go are you using (go version)?

Go 1.7.1
eg 69f6f5b

What operating system and processor architecture are you using (go env)?

MacOSX 10.12 Sierra (Darwin) x64

What did you do?

Given the template

package egtemplates

import (
    "fmt"
    "github.com/Sirupsen/logrus"
)

func before(vlog logrus.Logger, format string, args ...interface{}) {
    vlog.Errorf(fmt.Sprintf(format, args...))
}

func after(vlog logrus.Logger, format string, args ...interface{}) {
    vlog.Errorf(format, args...)
}

and the test file

package test

import (
    "fmt"

    "github.com/Sirupsen/logrus"
)

func articleCIPQ(vlog logrus.Logger) {
    vlog.Errorf(fmt.Sprintf("Table %s: %s", "something", "err"))
}

I executed eg -t egtemplates/logrus-errorf.go -v ./egtemplates/test/myfile.go.

What did you expect to see?

=== egtemplates/test/myfile.go (1 matches)
package test

import (
    "fmt"

    "github.com/Sirupsen/logrus"
)

func articleCIPQ(vlog logrus.Logger) {
    vlog.Errorf("Table %s: %s", "something", "err")
}

What did you see instead?

No substitutions, but no errors either.