jrDev

Master the real-world skills every junior developer needs.

Reading Other People's Code

Reading Other People’s Code

As a junior developer, you’re going to read a lot of code that wasn’t written by you. Some of it will be beautiful, and some of it will be… well, let’s call it “challenging.”

The Empathy Rule

Before you judge a messy piece of code, remember:

  1. You weren’t there: You don’t know the deadline they were facing.
  2. Code evolves: What was once clean might have been changed by 10 different people over 5 years.
  3. Knowledge grows: The person who wrote it might know much more now than they did then.

Step-by-Step: The “Empathy First” Approach

  1. Read for intent: What was the author trying to achieve?
  2. Look for patterns: Does this person like using short, descriptive functions? Or do they prefer one large, comprehensive function?
  3. Don’t assume “different” is “bad”: Just because they use a different style than you doesn’t mean it’s wrong.
  4. Find the “why”: Read the comments (if they exist) and the Git commit messages to understand the context.

Practical Strategy: The “Git Blame” Tool

Use git blame (or your IDE’s “Annotate” feature) to see:

  • Who wrote a specific line.
  • When it was written.
  • The commit message associated with it.
    Git Blame Output:
    [8a2f1c] 2022-03-15  John Doe: Fix session timeout bug
    [4c5d6e] 2023-11-10  Jane Smith: Add logging for better debugging

Real-World Example: The “Mysterious Loop”

You find a complex loop that seems unnecessary. You check the git log and find a commit from 2 years ago: “Fix: Handling edge case for Leap Year calculations.” Suddenly, the complexity makes sense!

Mental Model: The Conversation

Think of reading someone else’s code as a one-way conversation. The code is telling you a story about how it solves a problem. Your job is to listen and understand, not to interrupt with your own opinions (until you’re ready to make a pull request!).

Practical Strategy: Learn from the Best

Want to get better at reading code? Read open-source projects. Go to GitHub, find a library you use (like lodash or express), and read through their source code. Look at how they name their variables and how they structure their folders.

Common Mistake: “The Style Snob”

Don’t spend time reformatting someone else’s code just because you don’t like where they put their braces. Focus on the behavior and correctness of the code first.

Next: Common Reading Mistakes