adding a warning, trying to fix linter

Author: tlhunter

integration-tests/esbuild.spec.js

@@ -27,5 +27,5 @@ try {
   console.error(err)
   process.exit(1)
 } finally {
-    process.chdir(CWD)
+  process.chdir(CWD)
 }

integration-tests/esbuild/package.json

@@ -16,5 +16,9 @@
     "apm"
   ],
   "author": "Thomas Hunter II <tlhunter@datadog.com>",
-  "license": "ISC"
+  "license": "ISC",
+  "dependencies": {
+    "esbuild": "0.16.12",
+    "express": "^4.16.2"
+  }
 }

packages/datadog-esbuild/index.js

@@ -3,6 +3,8 @@ const NAMESPACE = 'datadog'
 const instrumented = Object.keys(require('../datadog-instrumentations/src/helpers/hooks.js'))
 const rawBuiltins = require('module').builtinModules
 
+warnIfUnsupported()
+
 const builtins = new Set()
 
 for (const builtin of rawBuiltins) {
@@ -88,3 +90,13 @@ module.exports.setup = function (build) {
     }
   })
 }
+
+function warnIfUnsupported() {
+  const [major, minor] = process.versions.node.split('.').map(Number);
+  if (major < 14 || major == 14 && minor < 17) {
+    console.error('WARNING: Esbuild support isn\'t available for older versions of Node.js.')
+    console.error(`Expected: Node.js >= v14.17. Actual: Node.js = ${process.version}.`)
+    console.error('This application may build properly with this version of Node.js, but unless a')
+    console.error('more recent version is used at runtime, third party packages won\'t be instrumented.')
+  }
+}