feat: use blazediff instead of pixelmatch

package.json

@@ -48,6 +48,7 @@
     "@babel/core": "^7.8.7",
     "@babel/plugin-proposal-class-properties": "^7.8.3",
     "@babel/preset-env": "^7.8.7",
+    "@blazediff/core": "1.0.0",
     "@rollup/plugin-babel": "^5.2.1",
     "@rollup/plugin-json": "4.0.1",
     "@rollup/plugin-node-resolve": "6.0.0",
@@ -73,7 +74,6 @@
     "jest-puppeteer": "^10.0.1",
     "nunjucks": "3.2.4",
     "nyc": "15.0.0",
-    "pixelmatch": "5.1.0",
     "pngjs": "3.4.0",
     "postcss": "^8.4.21",
     "prettier": "2.8.5",

tests/e2e/samples.js

@@ -2,7 +2,7 @@ const chalk = require('chalk')
 const { spawnSync } = require('child_process')
 const fs = require('fs-extra')
 const path = require('path')
-const pixelmatch = require('pixelmatch')
+const blazediff = require('@blazediff/core')
 const { PNG } = require('pngjs')
 const { Cluster } = require('puppeteer-cluster')
 const os = require('os')
@@ -100,7 +100,7 @@ async function processSample(page, sample, command) {
 
   await page.goto(`file://${htmlPath}`)
 
-  let wait;
+  let wait
   do {
     //Wait for all intervals in the page to have been cleared
     await page.waitForFunction(() => window.activeIntervalCount === 0)
@@ -117,7 +117,11 @@ async function processSample(page, sample, command) {
     //After the network requests, timers, and intervals finish, if another request, timer, or interval is created then we need
     //to wait for that to finish before continuing on.
     wait = await page.evaluate(() => {
-      return !(window.activeIntervalCount === 0 && window.activeTimerCount === 0 && chart.w.globals.animationEnded)
+      return !(
+        window.activeIntervalCount === 0 &&
+        window.activeTimerCount === 0 &&
+        chart.w.globals.animationEnded
+      )
     })
   } while (wait)
 
@@ -151,7 +155,7 @@ async function processSample(page, sample, command) {
     // Compare screenshot to the original and throw error on differences
     const testImg = PNG.sync.read(testImgBuffer)
     // BUG: copy if original image doesn't exist and report in test results?
-    let originalImg;
+    let originalImg
     try {
       originalImg = PNG.sync.read(fs.readFileSync(originalImgPath))
     } catch (e) {
@@ -168,7 +172,7 @@ async function processSample(page, sample, command) {
     let err
 
     try {
-      numDiffs = pixelmatch(
+      numDiffs = blazediff(
         originalImg.data,
         testImg.data,
         diffImg.data,
@@ -180,7 +184,7 @@ async function processSample(page, sample, command) {
       err = e
     }
 
-    // Save screenshot even if pixelmatch failed (due to image size mismatch)
+    // Save screenshot even if blazediff failed (due to image size mismatch)
     if (numDiffs !== 0) {
       await fs.ensureDir(`${e2eDir}/diffs/${sample.dirName}`)
       fs.writeFileSync(`${e2eDir}/diffs/${relPath}.png`, testImgBuffer)
@@ -331,7 +335,11 @@ async function processSamples(command, paths, isCI) {
     )
 
     if (testsMissingSnapshots.length > 0) {
-      console.log(chalk.yellow.bold(`${testsMissingSnapshots.length} tests were missing snapshots to compare against. Those tests are:`))
+      console.log(
+        chalk.yellow.bold(
+          `${testsMissingSnapshots.length} tests were missing snapshots to compare against. Those tests are:`
+        )
+      )
       for (const testMissingSnapshot of testsMissingSnapshots) {
         console.log(chalk.yellow.bold(`${testMissingSnapshot}\n`))
       }

tests/e2e/spec/utils.js

@@ -1,6 +1,6 @@
 import fs from 'fs'
 import path from 'path'
-import pixelmatch from 'pixelmatch'
+import blazediff from '@blazediff/core'
 import { PNG } from 'pngjs'
 import puppeteer from 'puppeteer'
 import { setTimeout as promisifiedTimeout } from 'timers/promises'
@@ -36,7 +36,7 @@ export function chartVisualTest(type, filename, imageFilename, validate) {
           const diffImg = new PNG({ width, height })
 
           // BUG: fix threshold
-          const numDiffs = pixelmatch(
+          const numDiffs = blazediff(
             originalImg.data,
             testImg.data,
             diffImg.data,