test: rebalance test suite (#5972)

* test: glob no longer in use by test suite

* test: remove manual balancing of tests

* chore: remove tools package

* test: match workflow parallelism count to matrix machine count

* chore: npm audit fix

* chore: update documentation around test balancing

.github/workflows/workflow.yml

@@ -198,7 +198,7 @@ jobs:
         env:
           # split tests across multiple machines
           CI_NODE_INDEX: ${{ matrix.machine }}
-          CI_NODE_TOTAL: 4
+          CI_NODE_TOTAL: 5
         with:
           timeout_minutes: 30
           max_attempts: 3

CONTRIBUTING.md

@@ -51,12 +51,6 @@ See our [testing documentation](packages/build/tests/README.md) to learn about o
 
 After submitting the pull request, please make sure the Continuous Integration checks (GitHub actions) are passing.
 
-### Testing in CI
-
-To speed up CI, we load balance the tests across multiple machines. The information required to load balance the tests
-is stored in `tests-metadata.json`, and later used by our test [runner](ava.config.js#L10). To regenerate the data (e.g.
-when adding a new test file) run `npm test:measure` and commit the changes to GitHub.
-
 ### Testing locally
 
 The `@netlify/testing` package will need to be built regardless of which package you are working on. In order to do this

ava.base.js

@@ -1,30 +1,12 @@
-import fs, { existsSync } from 'fs'
-import path from 'path'
 import process from 'process'
 
-import { isCI } from 'ci-info'
 import * as execa from 'execa'
 
 const { execaCommand } = execa
 if (process.argv.includes('-w')) {
   execaCommand('tsc -w', { cleanup: true })
 }
 
-// `tests-metadata.json` is created by running `npx lerna run test:measure --scope @netlify/build`
-const testData = existsSync('tests-metadata.json') ? JSON.parse(fs.readFileSync('tests-metadata.json', 'utf-8')) : {}
-
-const getOrder = (file) => {
-  const fileRelative = path.relative(process.cwd(), file).replace(/\\/g, '/')
-  if (testData[fileRelative]) {
-    return testData[fileRelative].order
-  }
-
-  console.warn(`Missing test metadata for ${fileRelative}`)
-  return Number.MAX_SAFE_INTEGER
-}
-
-const sortTestFiles = (file1, file2) => getOrder(file1) - getOrder(file2)
-
 const config = {
   files: ['packages/**/tests/*.{cjs,mjs,js}', 'packages/**/tests/**/tests.{cjs,mjs,js}'],
   verbose: true,
@@ -34,8 +16,6 @@ const config = {
   environmentVariables: {
     FORCE_COLOR: '1',
   },
-  // we only sort in CI to split efficiently across machines
-  ...(isCI && { sortTestFiles }),
 }
 
 export default config