rama-utils 0.4.0

utilities crate for rama
Documentation 
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/// Trim surrounding whitespace and return `None` when nothing remains.
#[must_use]
pub fn trim_non_empty(value: &str) -> Option<&str> {
    let value = value.trim();
    (!value.is_empty()).then_some(value)
}

/// Trim surrounding whitespace and ASCII quote marks.
///
/// This accepts the presentation used by command-line configuration tools:
/// either single or double quote marks may occur at either edge. Whitespace is
/// trimmed again after the quote marks, and an empty result is returned as
/// `None`. The returned string is always a slice of the input.
#[must_use]
pub fn trim_ascii_quotes_non_empty(value: &str) -> Option<&str> {
    trim_non_empty(value)
        .map(|value| value.trim_matches(['\'', '"']))
        .and_then(trim_non_empty)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn trims_without_allocating() {
        let value = String::from("  value  ");
        let trimmed = trim_non_empty(&value).unwrap();
        assert_eq!(trimmed, "value");
        assert!(core::ptr::eq(trimmed.as_ptr(), value[2..].as_ptr()));

        assert_eq!(trim_non_empty(" \t\n "), None);
    }

    #[test]
    fn trims_ascii_quotes_and_inner_edge_whitespace() {
        for (value, expected) in [
            ("  'value'  ", Some("value")),
            ("\"  value  \"", Some("value")),
            ("'\"value\"'", Some("value")),
            ("  ''  ", None),
            (" \" \t \" ", None),
        ] {
            assert_eq!(trim_ascii_quotes_non_empty(value), expected);
        }
    }
}