test: add demonstration

Author: Hweinstock

core/aws-lsp-core/src/util/demo.test.ts

@@ -0,0 +1,29 @@
+import * as fs from 'fs'
+import * as assert from 'assert'
+import * as cp from 'child_process'
+
+describe('demo', function () {
+    const temporaryDir = '/tmp/myTestDirectory'
+
+    it('test', async function () {
+        // Create temporary dir and assert it exists.
+        fs.mkdirSync(temporaryDir, { recursive: true })
+        assert.ok(fs.existsSync(temporaryDir), 'does not exist directly after creating')
+
+        // Run a process that checks that it exists.
+        const result = new Promise((resolve, reject) => {
+            const proc = cp.spawn('ls', [temporaryDir])
+            proc.on('exit', function (code) {
+                resolve(code)
+            })
+            proc.stderr.on('data', function (data) {
+                reject(data.toString())
+            })
+        })
+        const r = await result
+        // Assert that process found the file
+        assert.strictEqual(r, 0, 'did not exit with 0')
+        assert.ok(fs.existsSync(temporaryDir), 'does not exist after the test')
+        fs.rmdirSync(temporaryDir, { recursive: true })
+    })
+})