---input---
echo 'testing \' quotes'
echo 'testing quotes\''
echo 'testing quotes\\'
echo 'testing quotes\\\\'
echo 'testing \'\'\'\\ quotes\''
echo 'testing quotes'
echo ''
echo '\''

---tokens---
'echo'        Keyword
' '           Text
"'testing \\' quotes'" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'testing quotes\\''" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'testing quotes\\\\'" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'testing quotes\\\\\\\\'" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'testing \\'\\'\\'\\\\ quotes\\''" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'testing quotes'" Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"''"          Literal.String.Single
'\n'          Text

'echo'        Keyword
' '           Text
"'\\''"       Literal.String.Single
'\n'          Text
