unwrap issues

[shyamrajprasad]

There is an issue when we have to unwrap characters at the start or at the end only. I am highlighting 4 issues in below examples.

%dw 2.0
import unwrap from dw::core::Strings
output application/json
---
{
  "a": unwrap(null, ""),
  "b": unwrap(null, '\0'),
  "c": unwrap("'abc'", "'"),
  "d": unwrap("AABabcBAA", 'A'),
  "e": unwrap("A", '#'),
  "f": unwrap("#A", '#'), //current ouptut is "A#", which is wrong and this is not available in input also. Output should be "A"
  "g": unwrap("A#", '#') // current output is "#A", which is wrong and this is not available in input also. Output should be "A",
  "h": unwrap("ABC", 'A'), //current output is "B", which is wrong, it should not remove C from the input. 
  "i": unwrap("ABC",'C') //current output is "B", which is wrong, it should not remove A from the input. 
}

My suggestion will be to update the unwrap function to consider the wrapping characters from the end or start. I have the below suggestions.

fun unwrap(text: String, wrapper: String): String = do {
    if(!startsWith(text, wrapper) and !endsWith(text, wrapper))
        text
    else if(startsWith(text, wrapper) and !endsWith(text, wrapper))
        text[1 to -1]
    else if(!startsWith(text, wrapper) and endsWith(text, wrapper))
        text[0 to -2]         
    else
        text[1 to -2] default text
}

[machaval]

Hi @shyamrajprasad though the bug you are reporting does exits, I don't think that the solution is the one I would suggest. For me it should only remove or unwrap if it starts and ends with the specified character.

So I would propose

@Since(version = "2.2.0")
fun unwrap(text: String, wrapper: String): String = do {
    if(!startsWith(text, wrapper) or !endsWith(text, wrapper)) //changing from and to or
        text
    else
        text[1 to -2] default text
}

So the output for your input is going to be

{
  "a": null,
  "b": null,
  "c": "abc",
  "d": "ABabcBA",
  "e": "A",
  "f": "#A",
  "g": "A#",
  "h": "ABC",
  "i": "ABC"
}

What are your thoughts?

[shyamrajprasad]

@machaval I am fine with this proposal.