Function trim_element

src/interface.rs:415–521

Not really meant to be public -- used by tests in some packages

(e: &Element)

/// Not really meant to be public -- used by tests in some packages
pub fn trim_element(e: &Element) {
    // "<mtext>this is text</mtext" results in 3 text children
    // these are combined into one child as it makes code downstream simpler
    const WHITESPACE: &[char] = &[' ', '\u{0009}', '\u{000A}', '\u{000D}'];      // Rust complains if I don't give this type (from an example)

    if is_leaf(*e) {
        // Assume it is HTML inside of the leaf -- turn the HTML into a string
        make_leaf_element(*e);
        return;
    }

    let mut single_text = "".to_string();
    for child in e.children() {
        match child {
            ChildOfElement::Element(c) => {
                    trim_element(&c);
            },
            ChildOfElement::Text(t) => {
                single_text += t.text();
                e.remove_child(child);
            },
            _ => {
                e.remove_child(child);
            }
        }
    }

    // CSS considers only space, tab, linefeed, and carriage return as collapsable whitespace
    let trimmed_text = single_text.trim_matches(WHITESPACE);
    if !(is_leaf(*e) || name(e) == "intent-literal" || single_text.is_empty()) {  // intent-literal comes from testing intent
        // FIX: we have a problem -- what should happen???
        // FIX: For now, just keep the children and ignore the text and log an error -- shouldn't panic/crash
        if !trimmed_text.is_empty() {
            error!("trim_element: both element and textual children which shouldn't happen -- ignoring text '{}'", single_text);
        }
        return;
    }
    if e.children().is_empty() && !single_text.is_empty() {
        // debug!("Combining text in {}: '{}' -> '{}'", e.name().local_part(), single_text, trimmed_text);
        e.set_text(trimmed_text);
    }

    fn make_leaf_element(mathml_leaf: Element) {
        // MathML leaves like <mn> really shouldn't have non-textual content, but you could have embedded HTML
        // Here, we take convert them to leaves by grabbing up all the text and making that the content
        // Potentially, we leave them and let (default) rules do something, but it makes other parts of the code
        //   messier because checking the text of a leaf becomes Option<&str> rather than just &str
        let children = mathml_leaf.children();
        if children.is_empty() {
            return;
        }

        // gather up the text
        let mut text ="".to_string();
        let mut previous_element_was_text = false;
        for child in children {
            let (child_text, space) = match child {
                ChildOfElement::Element(child) => {