What's the point of "=true" in this test?

[Bart Schaefer <schaefer@brasslantern.com>]

In Test/E01options.ztst, the line "foo4=bar7 =true":

  fn() {
    emulate -L zsh
    setopt warncreateglobal
    foo1=bar1
    unset foo1
    foo1=bar2
    local foo2=bar3
    unset foo2
    foo2=bar4
    typeset -g foo3
    foo3=bar5
    fn2() {
      foo3=bar6
    }
    foo4=bar7 =true
    (( foo5=8 ))
    integer foo6=9
    (( foo6=10 ))
  }
  fn
0:WARN_CREATE_GLOBAL option


This caused a spurious test failure for me because the "true" that was
found in my path was emitting debugging output (long story having to do
with tracking down a path-search issue in a different app).

I'm not exactly sure what to suggest here, except to note that most
other tests try to insulate themselves from the environment.  Is the
requirement in this case simply that an external command be run?