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option_parser: Simplify code for splitting on commas

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The parsing is now O(1) as we only consider each character in the input
once and further it removes the need for allocating memory for
reassembling the option parameter.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This commit is contained in:
Rob Bradford 2022-08-08 13:47:38 +01:00
parent 9990439829
commit 46b790b582
1 changed files with 29 additions and 17 deletions
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46
option_parser/src/lib.rs
View file

@ -40,26 +40,38 @@ type OptionParserResult<T> = std::result::Result<T, OptionParserError>;
fn split_commas_outside_brackets(s: &str) -> OptionParserResult<Vec<String>> {
let mut list: Vec<String> = Vec::new();
let mut opened_brackets: usize = 0;
for element in s.trim().split(',') {
if opened_brackets > 0 {
if let Some(last) = list.last_mut() {
*last = format!("{},{}", last, element);
} else {
return Err(OptionParserError::InvalidSyntax(s.to_owned()));
}
} else {
list.push(element.to_string());
}
let mut opened_brackets = 0;
let mut current = String::new();
opened_brackets += element.matches('[').count();
let closing_brackets = element.matches(']').count();
if closing_brackets > opened_brackets {
return Err(OptionParserError::InvalidSyntax(s.to_owned()));
} else {
opened_brackets -= closing_brackets;
for c in s.trim().chars() {
match c {
'[' => {
opened_brackets += 1;
current.push('[');
}
']' => {
opened_brackets -= 1;
if opened_brackets < 0 {
return Err(OptionParserError::InvalidSyntax(s.to_owned()));
}
current.push(']');
}
',' => {
if opened_brackets > 0 {
current.push(',')
} else {
list.push(current);
current = String::new();
}
}
c => current.push(c),
}
}
list.push(current);
if opened_brackets != 0 {
return Err(OptionParserError::InvalidSyntax(s.to_owned()));
}
Ok(list)
}