frankie/src/frankie.js

A snailish mocha reporter

var Base = require('mocha').reporters.Base;

var charm = require('./charm-wrapper');
var art = require('./art-loader');

class Frankie extends Base {
  constructor(runner) {
    super(runner);

    this.tests = 0;
    this.passes = 0;
    this.fails = 0;
    this.testHistory = [];

    this.snailHeight = art.snail1.height - 1;
    this.sunHeight = art.sun.height - 1;
    this.sunVerticalOffset = 5;

    this.minWidth = Math.floor(Base.window.width * 0.4);
    this.maxWidth = Math.floor(Base.window.width * 0.6);
    this.width = this.minWidth;

    this.snailState = 1;

    runner.on('start', this.onStart.bind(this));
    runner.on('pass', this.onPass.bind(this));
    runner.on('fail', this.onFail.bind(this));
    runner.on('end', this.onEnd.bind(this));
  }

  onStart() {
    Base.cursor.hide();
    charm.clearVerticalSpace(this.snailHeight + this.sunVerticalOffset);
    charm.down(this.sunVerticalOffset);
  }

  onPass() {
    this.recordTest(true);
    this.draw();
  }

  onFail() {
    this.recordTest(false);
    this.draw();
  }

  onEnd() {
    Base.cursor.show();
    charm.down(this.snailHeight);
    this.epilogue();
  }

  recordTest(pass) {
    this.tests += 1;

    // increment `passes` or `failures`
    if (pass) this.passes += 1;
    else this.fails += 1;

    // add result to `testHistory`
    this.testHistory.push(pass);

    if (this.testHistory.length === this.width) {
      this.width = this.minWidth + 
        Math.floor(Math.random() * (this.maxWidth - this.minWidth));
    } else if (this.testHistory.length > this.width) {
      this.testHistory.shift();
      
      if (this.tests % 3 === 2) this.testHistory.shift();
    } 

    // transition snail state (roughly) every 10 tests
    if (this.tests % 10 === 9) {
      this.transitionSnailState();
    }
  }

  transitionSnailState() {
    if (this.snailState === 1 || this.snailState === 3) {
      this.snailState = 2;
    } else if (this.snailState === 2) {
      this.snailState = Math.random() < .5 ? 1 : 3;
    }
  }

  drawTrail() {
    const length = this.testHistory.length;
    let state;

    charm.down(this.snailHeight - 1);

    for (let i = 0; i < length; i++) {
      state = this.testHistory[i];

      charm
        .foreground(state ? 'green' : 'red')
        .write(art.trail.art);
    }

    return charm
      .up(this.snailHeight - 1)
      .left(art.trail.width * length);
  }

  drawSnail(offset) {
    const snail = 'snail' + this.snailState;

    return charm
      .foreground('black')
      .writeOffset(offset, art[snail].art);
  }

  drawSun() {
    const sun = this.tests % 10 > 7 ? 'sun2' : 'sun';

    charm
      .up(this.sunVerticalOffset + 1)
      .foreground('yellow')
      .drawArt(art[sun].art);
  }

  draw() {
    this.drawSnail(this.testHistory.length);
    this.drawSun();
    this.drawTrail();
  }
}

module.exports = Frankie;