create-new-app/modules/makeTable.js

Easily generate a new React application, optionally with Express & MongoDB.

/*
  This module is used to create fancy tables that display
  information when using the command `cna --mongoHelp`.
  It's also used internally for the `checkDependencies` module.
*/

const removeAnsiChars = require('./removeAnsiChars')
const thinTable = {
  h: '─',
  v: '│',
  tl: '┌',
  t: '┬',
  tr: '┐',
  l: '├',
  m: '┼',
  r: '┤',
  bl: '└',
  b: '┴',
  br: '┘',
}
const thickTable = {
  h: '━',
  v: '┃',
  tl: '┏',
  t: '┳',
  tr: '┓',
  l: '┣',
  m: '╋',
  r: '┫',
  bl: '┗',
  b: '┻',
  br: '┛',
}
const curveCorners = {tl: '╭', tr: '╮', bl: '╰', br: '╯'}

// For each column, find the widest length item.
function getColumnWidths(rows) {
  const columnWidths = []

  // Iterate through each of the rows.
  for (let i = 0; i < rows.length; i++) {
    const row = rows[i]

    // Iterate through each item for the current row.
    for (let j = 0; j < row.length; j++) {
      const existingColWidth = columnWidths[j] || 0
      const lengths = row[j]
        .split('\n')
        .map(text => removeAnsiChars(text).length)
      const currentColWidth = Math.max(...lengths)

      if (currentColWidth > existingColWidth) columnWidths[j] = currentColWidth
    }
  }

  return columnWidths
}

function createTableRow({
  row,
  columnWidths,
  centered,
  colors,
  padding,
  tableType,
  makeTop,
}) {
  const cells = row.map(r => (Array.isArray(r) ? r : r.split('\n')))
  const cellHeight = Math.max(...cells.map(cell => cell.length))
  const {l, m, r, h, v} = tableType
  const results = []

  // Cells may be multi-line.
  // Iterate through each line for this single row of cells.
  for (let i = 0; i < cellHeight; i++) {
    const line = cells.map((cell, j) => {
      const colorizer = typeof colors[j] === 'function' ? colors[j] : x => x
      const colWidth = columnWidths[j]
      const currentLine = cell[i] || ''
      const lineLength = removeAnsiChars(currentLine).length
      const lengthDiff = colWidth - lineLength
      const leftPad = ' '.repeat(
        centered ? Math.floor(lengthDiff / 2 + padding) : padding,
      )
      const rightPad = ' '.repeat(
        centered ? Math.ceil(lengthDiff / 2 + padding) : padding + lengthDiff,
      )

      return leftPad + colorizer(currentLine) + rightPad
    })

    results.push(v + line.join(v) + v)
  }

  // Conditionally add the top border of the row.
  if (makeTop) {
    const top = l + columnWidths.map(w => h.repeat(padding * 2 + w)).join(m) + r
    results.unshift(top)
  }

  return results
}

// Because `.flat()` isn't widely supported yet :/
function flatten(arr) {
  return arr.reduce(
    (acc, item) =>
      Array.isArray(item) ? [...acc, ...flatten(item)] : [...acc, item],
    [],
  )
}

function makeTable(rows, options = {}) {
  const columnWidths = getColumnWidths(rows)
  const {rounded, thick, centered, colors = [], padding = 1} = options
  const tableType = rounded
    ? {...thinTable, ...curveCorners}
    : thick
    ? thickTable
    : thinTable
  const {h, tl, t, tr, bl, b, br} = tableType
  const createTableTopBorder = () =>
    tl + columnWidths.map(w => h.repeat(w + padding * 2)).join(t) + tr
  const createTableBottomBorder = () =>
    bl + columnWidths.map(w => h.repeat(w + padding * 2)).join(b) + br

  return [
    createTableTopBorder(),
    ...flatten(
      rows.map((row, i) =>
        createTableRow({
          row,
          columnWidths,
          centered,
          colors,
          padding,
          tableType,
          makeTop: !!i,
        }),
      ),
    ),
    createTableBottomBorder(),
  ].join('\n')
}

module.exports = makeTable