document.getSelection with img.alt text

getSelectionWithAlt.ts

function isImg(node: Node):node is HTMLImageElement{
    return node.nodeName==='IMG'
}
function selectionToFragment(){
    const s = document.getSelection()
    const r = s!.getRangeAt(0)
    return r.cloneContents()
}
function getTextFromFragment(f: DocumentFragment) {
    const walker = document.createTreeWalker(f, NodeFilter.SHOW_ELEMENT | NodeFilter.SHOW_TEXT,
        {
            acceptNode: (node) => node.hasChildNodes()
                ? NodeFilter.FILTER_SKIP
                : NodeFilter.FILTER_ACCEPT
        }
    )
    const text: (string | Node | null)[] = [];
    let currentNode: Node | null = walker.nextNode();
    while (currentNode) {
        text.push(isImg(currentNode) ? currentNode.alt : currentNode.textContent);
        currentNode = walker.nextNode();
    }
    return text.join("")
}
function selectionToText(){
    return getTextFromFragment(selectionToFragment())
}
function selectionToHtml(){
    const div = document.createElement('div');
    div.appendChild(selectionToFragment());
    return div.innerHTML
}
console.log(selectionToHtml())

https://www.typescriptlang.org/play?#code/FAMwrgdgxgLglgewgKgAQwE4FMsHUCGANgNZYYAUIAXKgCIJRgC2WEMAYhvgOYtsCUqAN7BUY1FCQBnGKgDuRUhlQBeVABMGzVjAB0UbPhhYAKtjyKylADSoAcgnVZ2cQsYy6AygAkA8rgB9AFEAGSCAWSC7E1QAH3tHZ1d3Lz9AkyCADRNrUXF8kXyi8XwoKCwABxgHJxpyCETBFQA+VAanXQALfCkAYU7XdRqsKXJ+POLJ1AB+BKcXNzJddgBJEIyAJQDPAGkVgAUJqaKaYYWU1fWgrYBBXt6g-ZMj-IBfI-H8wixZRgxsNjDU6JOJtMCEQhHOQDb6och-AHVEFqBQkJYQLAADyRTjGgkKkwAnnAsIR1BIwP8dMMju93uBoPAkKg4FIVkxuPVEsCnPwaO0sCypKhvCZwiF2TwsEFvnxZASxNgYJSIG1EroBXZ8CxVCo1AByFbhADi+uA9MgsEQquM2N8GBubi5tTmWHxRyVKqF7M5AsEswFuiIsn56ttMF6SGMbHNoEtTNV3B+nlJWCtSFwcBgnUdMDGwiOkggMlQwrUmkYct0SZgKe+6YgYyOcBAcIAhFJBJ6MKqAES9wvSWTKNRSas-Db4CBJm55gAMn3ERZLrbUHighCQWEjbB0o0XYmXsnDqlQN3++EJuhAGAQTHImBwBDRFBA-H4uiY+AqD6xMHtuYfgAVggcCNv2B6oN2Np-rGQA