forked from extern/nushell
Prevent cubic time on nested parentheses (#10467)
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@ -1425,6 +1425,21 @@ pub fn parse_range(working_set: &mut StateWorkingSet, span: Span) -> Expression
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return garbage(span);
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}
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};
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// Avoid calling sub-parsers on unmatched parens, to prevent quadratic time on things like ((((1..2))))
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// No need to call the expensive parse_value on "((((1"
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if dotdot_pos[0] > 0 {
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let (_tokens, err) = lex(
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&contents[..dotdot_pos[0]],
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span.start,
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&[],
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&[b'.', b'?'],
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true,
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);
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if let Some(_err) = err {
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working_set.error(ParseError::Expected("Valid expression before ..", span));
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return garbage(span);
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}
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}
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let (inclusion, range_op_str, range_op_span) = if let Some(pos) = token.find("..<") {
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if pos == range_op_pos {
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