From 0b1e844a0fced54aeacb66ba0352bc2e455507ee Mon Sep 17 00:00:00 2001
From: ZiJian Liu <Lxxyxzj@gmail.com>
Date: Tue, 29 Dec 2020 01:06:34 +0800
Subject: [PATCH] test: increase coverage for events

1. test EventEmitter.setMaxListeners with invalid listener count
https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L171

2. test EventEmitter.setMaxListeners with invalid emitter
https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L186

3. test getEventListeners with invalid emiiter
Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L706

4. test events.once with options: null
Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/events.js.html#L712

5. add test case for inspect new Event()
Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/internal/event_target.js.html#L111

6. add test case for insepct new EventTarget()
Refs: https://coverage.nodejs.org/coverage-0b6d3070a176d437/lib/internal/event_target.js.html#L446

7. add test case for Event and EventTarget constructor name
---
 .../test-event-emitter-max-listeners.js       | 14 +++++++++
 test/parallel/test-events-once.js             | 13 ++++++++
 .../test-events-static-geteventlisteners.js   |  7 +++++
 test/parallel/test-eventtarget.js             | 31 ++++++++++++++++++-
 4 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/test/parallel/test-event-emitter-max-listeners.js b/test/parallel/test-event-emitter-max-listeners.js
index d1ac013bfb239f..a881bf86497f16 100644
--- a/test/parallel/test-event-emitter-max-listeners.js
+++ b/test/parallel/test-event-emitter-max-listeners.js
@@ -56,3 +56,17 @@ for (const obj of throwsObjs) {
 }
 
 e.emit('maxListeners');
+
+{
+  const { EventEmitter, defaultMaxListeners } = events;
+  for (const obj of throwsObjs) {
+    assert.throws(() => EventEmitter.setMaxListeners(obj), {
+      code: 'ERR_OUT_OF_RANGE',
+    });
+  }
+
+  assert.throws(
+    () => EventEmitter.setMaxListeners(defaultMaxListeners, 'INVALID_EMITTER'),
+    { code: 'ERR_INVALID_ARG_TYPE' }
+  );
+}
diff --git a/test/parallel/test-events-once.js b/test/parallel/test-events-once.js
index ea1963f0e58c1b..7c37f576c29fd3 100644
--- a/test/parallel/test-events-once.js
+++ b/test/parallel/test-events-once.js
@@ -23,6 +23,18 @@ async function onceAnEvent() {
   strictEqual(ee.listenerCount('myevent'), 0);
 }
 
+async function onceAnEventWithNullOptions() {
+  const ee = new EventEmitter();
+
+  process.nextTick(() => {
+    ee.emit('myevent', 42);
+  });
+
+  const [value] = await once(ee, 'myevent', null);
+  strictEqual(value, 42);
+}
+
+
 async function onceAnEventWithTwoArgs() {
   const ee = new EventEmitter();
 
@@ -195,6 +207,7 @@ async function eventTargetAbortSignalAfterEvent() {
 
 Promise.all([
   onceAnEvent(),
+  onceAnEventWithNullOptions(),
   onceAnEventWithTwoArgs(),
   catchesErrors(),
   stopListeningAfterCatchingError(),
diff --git a/test/parallel/test-events-static-geteventlisteners.js b/test/parallel/test-events-static-geteventlisteners.js
index d717ff74242f90..71d9b0a28ddc75 100644
--- a/test/parallel/test-events-static-geteventlisteners.js
+++ b/test/parallel/test-events-static-geteventlisteners.js
@@ -4,6 +4,7 @@ const common = require('../common');
 
 const {
   deepStrictEqual,
+  throws
 } = require('assert');
 
 const { getEventListeners, EventEmitter } = require('events');
@@ -34,3 +35,9 @@ const { getEventListeners, EventEmitter } = require('events');
   deepStrictEqual(getEventListeners(target, 'bar'), []);
   deepStrictEqual(getEventListeners(target, 'baz'), [fn1]);
 }
+
+{
+  throws(() => {
+    getEventListeners('INVALID_EMITTER');
+  }, /ERR_INVALID_ARG_TYPE/);
+}
diff --git a/test/parallel/test-eventtarget.js b/test/parallel/test-eventtarget.js
index 45c63e0dd18be3..dd3a5a106b5a01 100644
--- a/test/parallel/test-eventtarget.js
+++ b/test/parallel/test-eventtarget.js
@@ -13,7 +13,7 @@ const {
 
 const { once } = require('events');
 
-const { promisify } = require('util');
+const { promisify, inspect } = require('util');
 const delay = promisify(setTimeout);
 
 // The globals are defined.
@@ -541,3 +541,32 @@ let asyncTest = Promise.resolve();
   et.addEventListener('foo', listener);
   et.dispatchEvent(new Event('foo'));
 }
+
+{
+  const ev = new Event('test');
+  const evConstructorName = inspect(ev, {
+    depth: -1
+  });
+  strictEqual(evConstructorName, 'Event');
+
+  const inspectResult = inspect(ev, {
+    depth: 1
+  });
+  ok(inspectResult.includes('Event'));
+}
+
+{
+  const et = new EventTarget();
+  const inspectResult = inspect(et, {
+    depth: 1
+  });
+  ok(inspectResult.includes('EventTarget'));
+}
+
+{
+  const ev = new Event('test');
+  strictEqual(ev.constructor.name, 'Event');
+
+  const et = new EventTarget();
+  strictEqual(et.constructor.name, 'EventTarget');
+}