tests/heredoctest.py

tests: replace "cp -r" with "cp -R"

The POSIX documentation about "cp" [1] says:

  ....

  RATIONALE
    ....
    Earlier versions of this standard included support for the -r option to
    copy file hierarchies. The -r option is historical practice on BSD and
    BSD-derived systems. This option is no longer specified by POSIX.1-2008
    but may be present in some implementations. The -R option was added as a
    close synonym to the -r option, selected for consistency with all other
    options in this volume of POSIX.1-2008 that do recursive directory
    descent.

    The difference between -R and the removed -r option is in the treatment
    by cp of file types other than regular and directory. It was
    implementation-defined how the - option treated special files to allow
    both historical implementations and those that chose to support -r with
    the same abilities as -R defined by this volume of POSIX.1-2008. The
    original -r flag, for historic reasons, did not handle special files any
    differently from regular files, but always read the file and copied its
    contents. This had obvious problems in the presence of special file
    types; for example, character devices, FIFOs, and sockets.
    ....

  ....

  Issue 6
    The -r option is marked obsolescent.
    ....

  Issue 7
    ....
    The obsolescent -r option is removed.
    ....

  (No "Issue 8" yet)

Therefore it's clear that "cp -R" is strictly better than "cp -r".

The issue was discovered when running tests on OS X after 0d87b1caed92.

[1]: pubs.opengroup.org/onlinepubs/9699919799/utilities/cp.html

from __future__ import absolute_import, print_function

import sys

globalvars = {}
lines = sys.stdin.readlines()
while lines:
    l = lines.pop(0)
    if l.startswith('SALT'):
        print(l[:-1])
    elif l.startswith('>>> '):
        snippet = l[4:]
        while lines and lines[0].startswith('... '):
            l = lines.pop(0)
            snippet += l[4:]
        c = compile(snippet, '<heredoc>', 'single')
        try:
            exec(c, globalvars)
        except Exception as inst:
            print(repr(inst))