Test script:

  #!/bin/bash

  rev1="foo"
  rev2="\"bar\""
  rev3="'bar'"

  newrev1="${rev1//[\'\"]}"
  newrev2="${rev2//[\'\"]}"
  newrev3="${rev3//[\'\"]}"

  oldrev1=$(echo "${rev1}" | sed "s/['\"]//g")
  oldrev2=$(echo "${rev2}" | sed "s/['\"]//g")
  oldrev3=$(echo "${rev3}" | sed "s/['\"]//g")

  echo "$newrev1 vs. $oldrev1"
  echo "$newrev2 vs. $oldrev2"
  echo "$newrev3 vs. $oldrev3"

expected output:

  foo vs. foo
  bar vs. bar
  bar vs. bar