Name: What A Test Plan Is And Why Every Code Review Needs One
Uploaded: 2022-04-09T18:34:09+00:00
Duration: 5 min 46 s
Description: In this video, we explore the value of including a clear test plan or demo with every code review

What A Test Plan Is And Why Every Code Review Needs One

In this video, we explore the value of including a **clear test plan or demo** with every code review. This simple but often overlooked practice builds trust, improves collaboration, and turns code reviews into lasting pieces of product and engineering history.

### Key Takeaways:

- **We always include a test plan or demo**: Whether it's a video, GIF, image, or command-line instruction, we attach an artifact that shows what our code does—especially when it impacts visual or user-facing components.
- **We demonstrate the *actual* behavior of our code**: A video showing the happy-path functionality proves the feature works and saves reviewers from guessing or manually testing our changes.
- **We create long-term product context**: Test plans turn code reviews into searchable, durable documentation. They help future engineers (including ourselves) understand *why* a piece of code was written and what it was supposed to do.
- **We reduce risk when extending legacy code**: When we need to modify or build on old code, a past test plan often reveals how that code works, what features it powers, and how to avoid breaking it.
- **We invest a few minutes now to save hours later**: Including a test plan takes only 5–10 minutes but dramatically improves team empathy, speeds up reviews, and enhances the maintainability of the entire codebase.

This practice is one of the easiest and most impactful ways we show care for our teammates—and for the long-term health of the code we ship.

In this video, we explore the value of including a clear test plan or demo with every code review

[Masterclass] How To Do Amazing Code Review

Code review is one of the most effective ways to learn as a software engineer, especially for those earlier-in-career. Unfortunately, way too many engineering teams get it wrong with slow review speed and low quality comments.

There is a mountain of information in this presentation, so here's our 5 favorite points (in no particular order):
- **Code review is NOT for catching bugs** - Of course, if you find a bug in a PR (pull request), you should call it out, but that's not the primary purpose of code review. The core benefit of code review is to build up engineering culture, propagating best practices amongst the team and growing newer and more junior engineers.
- **Add deep context to your PRs** - Explain what your pull request does and the reasoning behind your approach. Also, *include a test plan.* A test plan is a demo showcasing what your code changes do; try to make it a video/gif, which is especially powerful if you work on front-end (Android/iOS/web). If you can't do a video, try attaching a screenshot or a set of commands to run tests.
- **One diff, one thesis** - Every PR should be focused and atomic: Don't jam the entire new feature you just coded up in a single 1,000+ line PR. Huge commits are hard to review, and your teammates will hate you for it. For the vast majority of cases, you can break down your PRs to 25-250 lines of code.
- **Read others' code reviews** - Similar to so many other things in tech, stand on the shoulders of giants where you can. With code review, this means looking at how senior+ engineers on your team comment on reviews. Try to find patterns in the issues they're finding and incorporate it into how you review code. Revisions that have been rejected with changes requested are a gold mine for this learning.
- **Code review MUST be fast** - When we say fast, we mean that feedback should arrive in <24 hours. What a lot of engineers don't realize is that code review delay is multiplicative: Sometimes commit will need 3-5 revisions before they're able to be merged. If turnaround is 2+ days, this can easily lead to commits taking weeks to land, which is far too slow.

A lot of the terminology in this video is Meta specific. If you're more used to GitHub:
- Diff review = Pull request
- Diff = Commit

Related resources:
- ["How to give better code reviews without full business context?"](https://www.jointaro.com/question/vio35mw1SYWM8AYojB2w/how-to-give-better-code-reviews-without-full-business-context/)
- ["How to review code in another language/ from another team?"](https://www.jointaro.com/question/B79W3aWc8xMB8cCULFdJ/how-to-review-code-in-another-language-from-another-team/)
- [Presentation Slides](https://docs.google.com/presentation/d/1koyIR9K_CtESD7Vnh3GQOE-svFW-ngrQeEAduSAoH0w/edit)