@prantlf/faucet/index.js

Human-readable TAP reporter/formatter.

const through2 = require('through2')
const duplexer = require('duplexer3')
const Parser = require('tap-parser')
const { sprintf } = require('sprintf-js')

module.exports = opts => {
  const { verbose, width } = opts || {}
  const tap = new Parser()
  const out = through2()
  let test, lastComment
  let id = 0
  const epilog = new Set()

  tap.on('comment', comment => {
    if (comment === 'fail 0') return // a mocha thing

    let hide
    if (test && test.ok) {
      if (test.assertions.length === 0) {
        let match
        if ((match = /^tests\s+(\d+)$/.exec(test.name))) {
          epilog.add('tests')
          if (+match[1]) {
            out.push('\r' + updateName(test.offset + 1, '# ' + test.name, 1))
          } else {
            hide = true
          }
        } else if ((match = /^pass\s+\d+$/.exec(test.name))) {
          epilog.add('pass')
          if (+match[1]) {
            out.push('\r' + updateName(test.offset + 1, '✓ ' + test.name, 32))
          } else {
            hide = true
          }
        } else if ((match = /^fail\s+\d+$/.exec(test.name))) {
          epilog.add('fail')
          if (+match[1]) {
            out.push('\r' + updateName(test.offset + 1, '⨯ ' + test.name, 31))
          } else {
            hide = true
          }
        } else if ((match = /^todo\s+\d+$/.exec(test.name))) {
          epilog.add('todo')
          if (+match[1]) {
            out.push('\r' + updateName(test.offset + 1, '> ' + test.name, 35))
          } else {
            hide = true
          }
        } else if ((match = /^skip\s+\d+$/.exec(test.name))) {
          epilog.add('skip')
          if (+match[1]) {
            out.push('\r' + updateName(test.offset + 1, '- ' + test.name, 34))
          } else {
            hide = true
          }
        } else if ((match = /^test count\(\d+\) != plan\([^)]+\)$/.exec(test.name))) {
          out.push('\r' + updateName(test.offset + 1, '? ' + test.name, 33))
        } else {
          hide = true
        }
      } else {
        const skipped = test.assertions.filter(({ skip }) => skip)
        let s
        if (skipped.length) {
          if (skipped.length === test.assertions.length) {
            s = updateName(test.offset + 1, '- ' + test.name, 34)
          } else {
            s = updateName(test.offset + 1, '✓ ' + test.name + ' (some skipped)', 32)
          }
        } else {
          s = updateName(test.offset + 1, '✓ ' + test.name, 32)
        }
        out.push('\r' + s)
      }
    }

    test = {
      name: comment.startsWith('#') ? comment.substring(1).trim() : comment.trim(),
      assertions: [],
      offset: 0,
      ok: true
    }
    if (!hide) {
      out.push('\r\x1b[K\n')
    }
    lastComment = true
  })

  tap.on('assert', res => {
    lastComment = false
    const ok = res.ok ? 'ok' : 'not ok'
    const c = res.ok ? 32 : res.todo ? 35 : 31
    if (!test) {
      // mocha produces TAP results this way, whatever
      const s = res.name ? trim(res.name.trim()) : ''
      out.push(sprintf(
        '\x1b[1m\x1b[' + c + 'm%s\x1b[0m\n',
        trim((res.ok ? '✓' : res.todo ? '>' : '⨯') + ' ' + s, res.ok)
      ))
      const diag = printDiag(res.diag)
      if (diag) {
        out.push(diag)
      }
      return
    }

    if (!res.id) {
      res.id = ++id
    }

    const fmt = '\r  %s \x1b[1m\x1b[' + c + 'm%d\x1b[0m %s\x1b[K'
    let str = sprintf(fmt, ok, res.id, res.name ? trim(res.name, res.ok) : '')

    if (res.ok && verbose) {
      str += '\n'
    }
    if (!res.ok) {
      const y = (++test.offset) + 1
      str += '\n'
      if (test.ok) {
        if (verbose) {
          str += '\n'
        }
        str += updateName(y, (res.todo ? '>' : '⨯') + ' ' + test.name, res.todo ? 35 : 31)
      }
      str += printDiag(res.diag)
      test.ok = false
    }
    out.push(str)
    test.assertions.push(res)
  })

  tap.on('extra', extra => {
    if (!test || test.assertions.length === 0) return
    const last = test.assertions[test.assertions.length - 1]
    if (!last.ok) {
      out.push(extra.split('\n').map(line => `  ${line}`).join('\n') + '\n')
    }
  })

  tap.on('complete', res => {
    let line
    const lineBreak = () => {
      if (line) {
        out.push('\n')
      } else {
        line = true
      }
    }

    let empty
    if (!lastComment) {
      out.push('\r\x1b[K\n')
    }
    if (res.bailout) {
      lineBreak()
      out.push(updateName(1, '! ' + res.bailout, 31))
    }
    if (res.plan.skipReason) {
      lineBreak()
      if (res.plan.skipReason === 'no tests found') {
        empty = true
        out.push(updateName(1, '! ' + res.plan.skipReason, 31))
      } else {
        out.push(updateName(1, '- ' + res.plan.skipReason, 34))
      }
    }
    let pass = res.pass - res.skip
    let fail = res.fail - res.todo
    if (fail < 0) {
      pass -= res.todo
      fail = 0
    }
    if (!test) {
      if (res.count) {
        lineBreak()
        out.push(updateName(1, '# tests ' + res.count, 1))
      }
      if (pass) {
        lineBreak()
        out.push(updateName(1, '✓ pass  ' + pass, 32))
      }
      if (fail) {
        lineBreak()
        out.push(updateName(1, '⨯ fail  ' + fail, 31))
      }
      if (res.todo) {
        lineBreak()
        out.push(updateName(1, '> todo  ' + res.todo, 35))
      }
      if (res.skip) {
        lineBreak()
        out.push(updateName(1, '- skip  ' + res.skip, 34))
      }
    } else {
      if (!epilog.has('tests') && res.count) {
        lineBreak()
        out.push(updateName(test.offset + 1, '# tests ' + res.count, 1))
      }
      if (!epilog.has('pass') && pass) {
        lineBreak()
        out.push(updateName(test.offset + 1, '✓ pass  ' + pass, 32))
      }
      if (!epilog.has('fail') && fail) {
        lineBreak()
        out.push(updateName(test.offset + 1, '⨯ fail  ' + fail, 31))
      }
      if (!epilog.has('todo') && res.todo) {
        lineBreak()
        out.push(updateName(test.offset + 1, '> todo  ' + res.todo, 35))
      }
      if (!epilog.has('skip') && res.skip) {
        lineBreak()
        out.push(updateName(test.offset + 1, '- skip  ' + res.skip, 34))
      }
    }

    out.push(null)

    dup.emit('complete', res)
    if (!res.ok || empty) dup.emit('fail')
    dup.exitCode = res.ok && !empty ? 0 : 1
  })

  const dup = duplexer(tap, out)
  return dup

  function trim (s, ok) {
    if (width && s.length > width - 2) {
      const more = ok ? 0 : 4
      s = s.slice(0, width - 5 - more) + '...'
    }
    return s
  }

  function updateName (y, str, c) {
    return '\x1b[' + y + 'A' +
            '\x1b[1G' +
            '\x1b[1m\x1b[' + c + 'm' +
            trim(str) +
            '\x1b[0m' +
            '\x1b[' + y + 'B\x1b[1G'
  }

  function printArray (lines, indent, items) {
    for (const item of items) {
      lines.push(indent + item + '\n')
    }
  }

  function printObject (lines, indent, diag) {
    for (const key in diag) {
      let val = diag[key]
      if (key === 'stack') {
        if (verbose) {
          val = '\n' + val
            .split('\n')
            .map((line, index) => index ? `      ${line}` : `        ${line}`)
            .join('\n')
        } else {
          continue
        }
      }
      if (val) {
        if (Array.isArray(val)) {
          lines.push(indent + (key + ':').padEnd(10) + '\n')
          printArray(lines, indent + '  ', val)
          continue
        }
        if (typeof val === 'object') {
          lines.push(indent + (key + ':').padEnd(10) + '\n')
          printObject(lines, indent + '  ', val)
          continue
        }
      }
      lines.push(indent + (key + ':').padEnd(10) + val + '\n')
    }
  }

  function printDiag (diag) {
    if (diag) {
      const lines = ['    ---\n']
      printObject(lines, '      ', diag)
      lines.push('    ...\n')
      return lines.join('')
    }
    return ''
  }
}