emoji split in word wrap

[mscalora]

Problem Summary

Emoji is being split in half nu the wordwrap mechanism

Expected Result (screen shot if possible)

emoji should wrap instead of being split

Actual Result (screen shot if possible)

illegal char error symbol

Environment Information

• OS: Mac

• Terminal Emulator: iTerm

Steps to Reproduce

1. run this code form example folder:

const Table = require("../")

process.stdout.columns = process.argv[2] && parseInt(process.argv[2]) || 25

console.log("Starting... (user CTRL-C to give up)")
console.log("\"fix\" by uncommenting line format.js:70")

let output = new Table([
  {minWidth: 6, shrink: 0},
  {minWidth: 12, shrink: 1},
  {minWidth: 24, shrink: 1000}
], [[
  "aaa bbb ccc",
  "aaa bbb ccc 😀😃😄😁 eee fff ggg hhh",
  "aaa bbb ccc ddd eee fff ggg hhh iii jjj kkk lll mmm nnn ooo ppp qqq rrr sss ttt"
]], {
  paddingLeft: 0,
  paddingRight: 0,
  marginTop: 0
}).render()

console.log(output)

Discussion

I did not to dig into this one very much, not sure if the cause is in the smartwrap module

[tecfu]

Options:

1. Embed a static array of emojis within the smartwrap module, and then refuse to wrap them.
2. Create option to set an array of character combinations that cannot be split, then pass that array to smartwrap.

Preferred option:
2.

[mscalora]

Doesn't the spread op [..."ccc 😀😃😄😁 eee"] idom correctly show where you can't split?

I implemented a string truncate using it that appears to always split chars in the right place.

// eslint-disable-next-line no-control-regex
const ansiMatcher = new RegExp("([^\u001B\u009B]*)([\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[-a-zA-Z\\d\\/#&.:=?%@~_]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PR-TZcf-ntqry=><~]))|$)", "g")

/**
 * split a unicode string into code points
 * @param {string} s - string with unicode
 * @return {Array<string>} - array of code points
 */
const splitUnicode = s => [...s]

/**
 * truncate a unicode string that may contain ansi and/or multi-column unicode characters
 * @param {string} s - string with unicode and/or multi-column unicode characters
 * @param {number} length - width in terminal char column
 * @return {string}
 */
Format.truncate = (s, length) => {
  let total = 0
  return s.replace(ansiMatcher, function (match, content, ansi) {
    if (total === length || 0) {
      // skip all visible content
      return ansi
    }
    let contentLength = Wcwidth(content)
    if (contentLength <= length - total) {
      // pass all visible content
      total += contentLength
      return content + ansi
    }
    // partial chunk
    let chars = splitUnicode(content)
    while (Wcwidth(chars.join("")) > length - total) {
      chars.pop()
    }
    content = chars.join("")
    // set total so the rest of content is skipped
    total = length
    return content + ansi
  })
}

-Mike