Process.run( ... ({ "stdin": "" }) ) fails - Pike-devel

8 Jan 2019


      Process.run fails if stdin is an empty string.  Here is a toy program
that demonstrates it:
-- cut here --
void run(string input)
{
  werror("Input: %O\n", input);
  werror("Result: %O\n", Process.run( ({ "od", "-c" }),
    			      ([ "stdin": input ]) ));
}
int main()
{
  run("foo");
  run("");
  return 0;
}
-- cut here --
The for invocation (which essentiall runs "echo foo | od -c") works
fine.  The second crashes with an error message: "Failed to convert
argument to a source".
This used to work in Pike 7.8, but fails in Pike 8.0.388 (in the
version distributed with Debian 9 ("stretch")), and on the 8.0 and
master branches in the Pike git repo.
The complete output I'm seeing is:
Input: "foo"
Result: ([ /* 3 elements */
  "exitcode": 0,
  "stderr": "",
  "stdout": "0000000   f   o   o\n"
    "0000003\n"
])
Input: ""
Failed to convert argument to a source
/usr/lib/pike8.0/modules/Shuffler.so:1: Shuffler.Shuffle()->add_source("")
/usr/lib/pike8.0/modules/Process.pmod:617:
    Process.run(({"od","-c"}),mapping[1])
run-stdin.pike:4: /main()->run("")
run-stdin.pike:11: /main()->main()