Replace jest with vitest

.eslintrc.json

@@ -31,8 +31,8 @@
   "overrides": [
     {
       "files": ["*.spec.ts"],
-      "plugins": ["jest"],
-      "extends": ["plugin:jest/recommended"]
+      "plugins": ["@vitest"],
+      "extends": ["plugin:@vitest/legacy-recommended"]
     }
   ]
 }

.github/workflows/test.yml

@@ -55,12 +55,8 @@ jobs:
       - name: Install dependencies
         run: pnpm install && pnpm add --global concurrently
 
-      - name: Build & Unit Test
-        run: concurrently --prefix none --group "pnpm:build" "pnpm:test"
-
-      - name: Smoke Test
-        # Don't collect coverage here as it overrides the unit test's coverage
-        run: pnpm test:smoke --coverage=false
+      - name: Build & Test
+        run: concurrently --prefix none --group "pnpm:build" "pnpm:test --coverage" "pnpm:test:smoke"
 
       - name: Submit coverage
         uses: coverallsapp/github-action@master

.vscode/extensions.json

@@ -3,6 +3,6 @@
     "dbaeumer.vscode-eslint",
     "esbenp.prettier-vscode",
     "editorconfig.editorconfig",
-    "orta.vscode-jest"
+    "vitest.explorer"
   ]
 }

.vscode/settings.json

@@ -1,6 +1,7 @@
 {
-  "jest.runMode": "watch",
-  "jest.jestCommandLine": "pnpm test --",
+  // For contributors with the Jest extension installed,
+  // it might incorrectly report errors in the suite
+  "jest.enable": false,
   "editor.codeActionsOnSave": {
     "source.fixAll.eslint": "explicit"
   },

bin/concurrently.spec.ts

@@ -9,6 +9,7 @@ import * as readline from 'readline';
 import * as Rx from 'rxjs';
 import { map } from 'rxjs/operators';
 import stringArgv from 'string-argv';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { escapeRegExp } from '../src/utils';
 

package.json

@@ -36,8 +36,8 @@
     "lint:fix": "pnpm run lint --fix",
     "prepublishOnly": "safe-publish-latest && pnpm run build",
     "report-coverage": "cat coverage/lcov.info | coveralls",
-    "test": "jest --selectProjects unit",
-    "test:smoke": "jest --selectProjects smoke",
+    "test": "vitest run --project unit",
+    "test:smoke": "vitest run --project smoke",
     "prepare": "husky"
   },
   "repository": {
@@ -65,16 +65,14 @@
   },
   "devDependencies": {
     "@hirez_io/observer-spy": "^2.2.0",
-    "@jest/types": "^30.0.0",
-    "@swc/core": "^1.7.23",
-    "@swc/jest": "^0.2.36",
-    "@types/jest": "^30.0.0",
     "@types/node": "^18.19.50",
     "@types/shell-quote": "^1.7.5",
     "@types/supports-color": "^8.1.3",
     "@types/yargs": "^17.0.33",
     "@typescript-eslint/eslint-plugin": "^7.18.0",
     "@typescript-eslint/parser": "^7.18.0",
+    "@vitest/coverage-v8": "^3.2.4",
+    "@vitest/eslint-plugin": "^1.3.4",
     "coveralls-next": "^5.0.0",
     "ctrlc-wrapper": "^0.0.4",
     "esbuild": "~0.25.0",
@@ -85,13 +83,12 @@
     "eslint-plugin-prettier": "^5.2.1",
     "eslint-plugin-simple-import-sort": "^12.1.1",
     "husky": "^9.1.5",
-    "jest": "^30.0.0",
-    "jest-create-mock-instance": "^2.0.0",
     "lint-staged": "^15.2.10",
     "prettier": "^3.0.3",
     "safe-publish-latest": "^2.0.0",
     "string-argv": "^0.3.2",
-    "typescript": "~5.2.2"
+    "typescript": "~5.2.2",
+    "vitest": "^3.2.4"
   },
   "files": [
     "dist",