lighthouse/plots/ab-screenshot

A/B Screenshot Comparison

This tools enables you to look at how two different versions of perf metrics measure real world sites.

Generating & viewing charts

# 1. Run measure two times (e.g two different versions of lighthouse)

# In /plots/
$ node measure.js

# Save the first results into another directory
$ mv ./out ./out-first

# (e.g. switch versions of lighthouse, modify algorithm)
$ node measure.js

# Switch to /plots/ab-screenshot
$ cd ab-screenshot

# Analyze the screenshot data to generate a summary file
# This will launch the screenshot viewer in the browser
$ node analyze.js -a ../out-first -b ../out-second

# If you need to open the screenshot viewer later
$ node open.js