chore: add discovery example tests (#841)

examples/discovery-mechanisms/test-2.js

@@ -0,0 +1,35 @@
+'use strict'
+
+const path = require('path')
+const execa = require('execa')
+const pWaitFor = require('p-wait-for')
+const uint8ArrayToString = require('uint8arrays/to-string')
+
+const discoveredCopy = 'Discovered:'
+
+async function test() {
+  const discoveredNodes = []
+
+  process.stdout.write('2.js\n')
+
+  const proc = execa('node', [path.join(__dirname, '2.js')], {
+    cwd: path.resolve(__dirname),
+    all: true
+  })
+
+  proc.all.on('data', async (data) => {
+    process.stdout.write(data)
+    const line = uint8ArrayToString(data)
+
+    if (line.includes(discoveredCopy)) {
+      const id = line.trim().split(discoveredCopy)[1]
+      discoveredNodes.push(id)
+    }
+  })
+
+  await pWaitFor(() => discoveredNodes.length === 2)
+
+  proc.kill()
+}
+
+module.exports = test