Add async iterator tests (#62)

Author: brianc

package.json

@@ -32,10 +32,17 @@
     "eslint-plugin-standard": "^3.0.1",
     "mocha": "^6.2.2",
     "pg": "^7.5.0",
+    "prettier": "^1.18.2",
     "stream-spec": "~0.3.5",
     "stream-tester": "0.0.5",
     "through": "~2.3.4"
   },
+  "prettier": {
+    "semi": false,
+    "printWidth": 120,
+    "trailingComma": "es5",
+    "singleQuote": true
+  },
   "dependencies": {
     "pg-cursor": "2.0.0"
   }

test/async-iterator.es6

@@ -0,0 +1,57 @@
+const QueryStream = require('../')
+const pg = require('pg')
+const assert = require('assert')
+
+const queryText = 'SELECT * FROM generate_series(0, 200) num'
+describe('Async iterator', () => {
+  it('works', async () => {
+    const stream = new QueryStream(queryText, [])
+    const client = new pg.Client()
+    await client.connect()
+    const query = client.query(stream)
+    const rows = []
+    for await (const row of query) {
+      rows.push(row)
+    }
+    assert.equal(rows.length, 201)
+    await client.end()
+  })
+
+  it('can async iterate and then do a query afterwards', async () => {
+    const stream = new QueryStream(queryText, [])
+    const client = new pg.Client()
+    await client.connect()
+    const query = client.query(stream)
+    const iteratorRows = []
+    for await (const row of query) {
+      iteratorRows.push(row)
+    }
+    assert.equal(iteratorRows.length, 201)
+    const { rows } = await client.query('SELECT NOW()')
+    assert.equal(rows.length, 1)
+    await client.end()
+  })
+
+  it('can async iterate multiple times with a pool', async () => {
+    const pool = new pg.Pool({ max: 1 })
+
+    const allRows = []
+    const run = async () => {
+      // get the client
+      const client = await pool.connect()
+      // stream some rows
+      const stream = new QueryStream(queryText, [])
+      const iteratorRows = []
+      client.query(stream)
+      for await (const row of stream) {
+        iteratorRows.push(row)
+        allRows.push(row)
+      }
+      assert.equal(iteratorRows.length, 201)
+      client.release()
+    }
+    await Promise.all([run(), run(), run()])
+    assert.equal(allRows.length, 603)
+    await pool.end()
+  })
+})

test/async-iterator.js

@@ -0,0 +1,4 @@
+// only newer versions of node support async iterator
+if (!process.version.startsWith('v8')) {
+  require('./async-iterator.es6')
+}

yarn.lock

@@ -1217,6 +1217,11 @@ prelude-ls@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/prelude-ls/-/prelude-ls-1.1.2.tgz#21932a549f5e52ffd9a827f570e04be62a97da54"
 
+prettier@^1.18.2:
+  version "1.18.2"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.18.2.tgz#6823e7c5900017b4bd3acf46fe9ac4b4d7bda9ea"
+  integrity sha512-OeHeMc0JhFE9idD4ZdtNibzY0+TPHSpSSb9h8FqtP+YnoZZ1sl8Vc9b1sasjfymH3SonAF4QcA2+mzHPhMvIiw==
+
 process-nextick-args@~1.0.6:
   version "1.0.7"
   resolved "https://registry.yarnpkg.com/process-nextick-args/-/process-nextick-args-1.0.7.tgz#150e20b756590ad3f91093f25a4f2ad8bff30ba3"