node test runner plugin

Author: zoeyTM

pnpm-lock.yaml

@@ -5,6 +5,7 @@ import {
   emptyTask,
   configVariable,
   globalOption,
+  HardhatUserConfig,
 } from "@ignored/hardhat-vnext/config";
 import HardhatNodeTestRunner from "@ignored/hardhat-vnext-node-test-runner";
 
@@ -93,7 +94,7 @@ const pluginExample = {
   ],
 };
 
-const config = {
+const config: HardhatUserConfig = {
   tasks: [
     exampleTaskOverride,
     testSolidityTask,

v-next/example-project/hardhat.config.js v-next/example-project/hardhat.config.ts

@@ -26,5 +26,8 @@
     "@types/node": "^20.14.9",
     "prettier": "3.2.5",
     "typescript": "~5.5.0"
+  },
+  "dependencies": {
+    "tsx": "^4.11.0"
   }
 }

v-next/example-project/package.json

@@ -1,8 +1,6 @@
 import assert from "node:assert/strict";
 import { describe, it } from "node:test";
 
-import hre from "@ignored/hardhat-vnext";
-
 describe("Example test", () => {
   it("should work", () => {
     assert.equal(1 + 1, 2);

v-next/example-project/test/example-test.js v-next/example-project/test/example-test.ts

@@ -196,6 +196,26 @@ Please add the property "type" with the value "module" in your package.json to e
       websiteTitle: "Invalid config",
       websiteDescription: `The configuration you provided is invalid. Please check the documentation to learn how to configure Hardhat correctly.`,
     },
+    TYPESCRIPT_NOT_INSTALLED: {
+      number: 17,
+      messageTemplate: `Your Hardhat project uses typescript, but it's not installed.
+
+Please run: npm install --save-dev typescript`,
+      websiteTitle: "typescript not installed",
+      websiteDescription: `You are running a Hardhat project that uses typescript, but it's not installed.
+
+Please run this and try again: \`npm install --save-dev typescript\``,
+    },
+    TSX_NOT_INSTALLED: {
+      number: 18,
+      messageTemplate: `Your Hardhat project uses typescript, but tsx is not installed.
+
+Please run: npm install --save-dev tsx`,
+      websiteTitle: "tsx not installed",
+      websiteDescription: `You are running a Hardhat project that uses typescript, but you haven't installed tsx.
+
+Please run this and try again: \`npm install --save-dev tsx\``,
+    },
   },
   INTERNAL: {
     ASSERTION_ERROR: {

v-next/hardhat-errors/src/descriptors.ts

@@ -60,6 +60,6 @@
     "@ignored/hardhat-vnext-errors": "workspace:^3.0.0-next.2",
     "@ignored/hardhat-vnext-node-test-reporter": "workspace:^3.0.0-next.2",
     "@ignored/hardhat-vnext-utils": "workspace:^3.0.0-next.2",
-    "ts-node": "^10.8.0"
+    "tsx": "^4.11.0"
   }
 }

v-next/hardhat-node-test-runner/package.json

@@ -3,10 +3,10 @@ import type { NewTaskActionFunction } from "@ignored/hardhat-vnext-core/types/ta
 
 import { resolve } from "node:path";
 import { run } from "node:test";
-import "tsx";
 
+import { HardhatError } from "@ignored/hardhat-vnext-errors";
 import hardhatTestReporter from "@ignored/hardhat-vnext-node-test-reporter";
-import { getAllFilesMatching } from "@ignored/hardhat-vnext-utils/fs";
+import { findUp, getAllFilesMatching } from "@ignored/hardhat-vnext-utils/fs";
 
 interface TestActionArguments {
   testFiles: string[];
@@ -39,16 +39,36 @@ async function getTestFiles(
   );
 }
 
+async function hasTypescriptConfig(): Promise<boolean> {
+  const hhConfig = await findUp("hardhat.config.ts");
+
+  return hhConfig !== undefined;
+}
+
 const runScriptWithHardhat: NewTaskActionFunction<TestActionArguments> = async (
   { testFiles, only },
   hre,
 ) => {
   const files = await getTestFiles(testFiles, hre.config);
 
-  if (files.some((f) => isTypescriptFile(f))) {
-    // @ts-expect-error -- typescript will complain about lack of type info for this import
-    // but we don't need it, we just need to load the module to run typescript tests
-    await import("ts-node/register/transpile-only");
+  // the second check is needed for the case of a user having a hardhat.config.ts file
+  // but all their test files are js files. probably an edge case, but we should handle it
+  if (files.some((f) => isTypescriptFile(f)) || (await hasTypescriptConfig())) {
+    try {
+      import.meta.resolve("typescript");
+    } catch {
+      throw new HardhatError(
+        HardhatError.ERRORS.GENERAL.TYPESCRIPT_NOT_INSTALLED,
+      );
+    }
+
+    try {
+      import.meta.resolve("tsx");
+    } catch {
+      throw new HardhatError(HardhatError.ERRORS.GENERAL.TSX_NOT_INSTALLED);
+    }
+
+    process.env.NODE_OPTIONS = "--import tsx";
   }
 
   run({ files, only }).compose(hardhatTestReporter).pipe(process.stdout);