#!/bin/bash
# Tests bash implementation of cat
#
#  Copyright (C) 2014 Mike Gerwitz
#
#  This file is part of pkgsh.
#
#  pkgsh is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
##

source src/coreutils/cat.sh

set -T

declare -r qcalled=$'\001'
trap _callset RETURN

_callset()
{
  # can't set a var because we're likely in a subshell
  if [ "${FUNCNAME[1]}" == quickcat ]; then
    # quickcat recurses
    if [ "${FUNCNAME[2]}" != quickcat ]; then
      echo -n "$qcalled"
    fi
  fi
}

_chk()
{
  local given="$1" expected="$2"

  [[ "$given" =~ "$qcalled"$ ]] \
    || assert -z "quickcat not called: $given"

  given="${given%$qcalled}"

  assert "$given" == "$expected"
}


_readall()
{
  local -r var="$1"
  IFS= read -rd '' "$var" || true
}


##
# Leading and trailing whitespace, be it spaces, newlines, or otherwise,
# should be retained (something that the shell does not normally like doing)
test-retains-leading-trailing-whitespace()
{
  _readall val < <( echo -e "\n   foo   \n" )
  _readall expected < <( command cat <( echo -n "$val" ) )
  _readall given < <( cat <( echo -n "$val" ) )
  _chk "$given" "$expected"
}


##
# If there is no trailing newline, one should not be added
test-does-not-add-trailing-whitespace()
{
  _readall expected < <( command cat <( echo -n foo ) )
  _readall given < <( cat <( echo -n foo ) )
  _chk "$given" "$expected"
}


##
# It is, after all, what `cat` is good at
test-concatenates-multiple-files()
{
  _readall expected < <( command cat <( echo -n foo ) <( echo "Bar" ) )
  _readall given < <( cat <( echo -n foo ) <( echo "Bar" ) )
  _chk "$given" "$expected"
}


##
# As by convention, `-` means `stdin` and can appear anywhere in the file
# list
test-can-read-stdin-via-dash()
{
  _readall expected < <( command cat <( echo -n foo ) - <<< "Baz" )
  _readall given < <( cat <( echo -n foo ) - <<< "Baz" )
  _chk "$given" "$expected"
}


##
# If no arguments are provided, input is accepted from `stdin`
test-defaults-to-stdin()
{
  _readall expected < <( command cat <<< "foo" )
  _readall given < <( cat <<< "foo" )
  _chk "$given" "$expected"
}


##
# We do not currently handle any options; defer to system binary
test-any-option-defers-to-binary()
{
  _readall given < <( cat -E <<< "foo" )

  # note that this assertion will implicitly ensure that quickcat was not
  # called; see _callset
  assert "$given" == 'foo$'$'\n'
}


test-concatenates-multiple-files
test-can-read-stdin-via-dash
test-defaults-to-stdin
test-retains-leading-trailing-whitespace
test-does-not-add-trailing-whitespace
test-any-option-defers-to-binary