add non optimal parallelization across 6 instances (#815)

* add non optimal parallelization across 6 instances

* randomize sequencer with deterministic ordering
disable fail-fast to allow more explicit failure reporting

* fixed tests sorting code ordering

.github/workflows/ci.yml

@@ -27,6 +27,12 @@ jobs:
   test:
     name: Test
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        instance: [ 0, 1, 2, 3, 4, 5]
+    env:
+      GH_INSTANCE_TOTAL: 6
     steps:
       - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
       - uses: actions/setup-node@270253e841af726300e85d718a5f606959b2903c
@@ -36,6 +42,8 @@ jobs:
 
       - run: npm ci
       - run: npm run test:ci
+        env:
+          GH_INSTANCE_INDEX: ${{ matrix.instance }}
 
       - uses: codecov/codecov-action@f32b3a3741e1053eb607407145bc9619351dc93b
         with:

jest.config.js

@@ -1,6 +1,7 @@
 module.exports = {
   preset: 'ts-jest',
   testRegex: '((\\.|/)(e2e|test|spec))\\.[jt]sx?$',
+  testSequencer: require.resolve('./jest.sequencer'),
   moduleNameMapper: {
     '@defichain/jellyfish-(.*)': '<rootDir>/packages/jellyfish-$1/src',
     '@defichain/testcontainers': '<rootDir>/packages/testcontainers/src',

jest.sequencer.js

@@ -0,0 +1,19 @@
+const Sequencer = require('@jest/test-sequencer').default
+const ShuffleSeed = require('shuffle-seed')
+
+class CustomSequencer extends Sequencer {
+  sort (tests) {
+    // In CI, GitHub Actions tests are parallelized across multiple instance
+    if (process.env.GH_INSTANCE_TOTAL) {
+      const total = parseInt(process.env.GH_INSTANCE_TOTAL, 10)
+      const index = parseInt(process.env.GH_INSTANCE_INDEX, 10)
+
+      return ShuffleSeed.shuffle(tests, 'deterministic')
+        .filter((_, i) => i % total === index)
+    }
+
+    return tests
+  }
+}
+
+module.exports = CustomSequencer

package.json

@@ -41,6 +41,7 @@
     "jest": "^27.3.1",
     "lerna": "^4.0.0",
     "lint-staged": "^11.2.6",
+    "shuffle-seed": "^1.1.6",
     "ts-jest": "^27.0.7",
     "typescript": "4.2.4",
     "wait-for-expect": "^3.0.2"