This week, I expanded my knowledge on the importance of code formatting in software development. Just as we rely on word processing software with spell check features to identify and correct spelling errors, developers should leverage code editors that offer formatting and linting capabilities to maintain code quality.
Why Use Static Analysis Tools
To enhance the quality of our code and reduce development time, it is essential for programmers to utilize static analysis tools. When collaborating on projects with multiple contributors, adherence to coding standards becomes crucial, as it allows others to read and understand the code more easily. This necessity has led to the emergence of various tools tailored to different programming languages. For my project this week, I chose to implement Prettier
for my JavaScript codebase. In addition to formatting tools, a linter is also essential. A linter assists developers in identifying overlooked errors that may not affect the program's execution but can lead to significant issues in the code if left unchecked. For this purpose, I selected ESLint
.
Prettier
To use Prettier, I installed it locally in my project with the following command:
npm install --save-dev --save-exact prettier
Next, I created two configuration files: .prettierrc
and .prettierignore
:
-
.prettierrc
: This configuration file contains the rules for formatting.
I left it as an empty object because I want to use the default Prettier's setup without overriding any rules.
-
.prettierignore
: This file lists the files or directories that Prettier should not format.
I included all the files and folders that I don't want Prettier will approach. Most of them are configuration files and self-generated files.
Notes:
- Both files must be placed in the root directory of the project.
- After installation, I can test Prettier's functionality by running:
npx prettier . --write
- To make it easier to run that command, I made a script that will run in command-line. Inside the
package.json
file, I added a new script namedformat
.
To use this, you just type this command:
npm run format
In addition to the local setup and command-line usage, Prettier can also be integrated into the code editor (such as VSCode) via an extension. Once installed, it automatically formats code upon saving a file.
Linter
ESLint
is a tool designed to identify and report on patterns in ECMAScript/JavaScript code, aiming to enhance code consistency and minimize bugs. You can install and configure ESLint
using:
npm init @eslint/config@latest
Upon executing this command, a series of questions will guide you through the setup in the terminal, and a new configuration file named .eslint.config.mjs
will be created. Since I am using ESLint
version 9.x, all configurations will be specified within this file. I also listed unnecessary files and folders for ESLint
to ignore using the ignore property.
To streamline the linting process, I added a script in package.json
for easier execution.
To run the script, you just type this command:
npm run lint
Editor Integration
While the aforementioned setup suffices for individual projects, ensuring a uniform development environment for all contributors is vital in collaborative settings. Therefore, I created a .vscode
folder in the root directory containing two files:
extensions.json
: This file lists the necessary extensions that developers should install when opening the project, providing prompts upon project launch.-
settings.json
: This configuration ensures that:- The editor formats code on save using Prettier.
- ESLint automatically fixes linting issues on save.
- ESLint validates JavaScript files.
- Prettier requires a configuration file to format the code.
By establishing the .vscode
folder with settings.json
and extensions.json
, I ensure that all contributors share a consistent development environment, with Prettier
and ESLint
seamlessly integrated into Visual Studio Code. This setup facilitates automatic code formatting and linting according to the project’s configuration, simplifying the maintenance of code quality and consistency.
Addressing Formatting Issues
After running
Prettier
, I identified a few files that required manual adjustments, primarily adding commas to the last elements of objects.Following the ESLint run, I discovered 13 issues, most of which were due to the use of the global object
process
, which does not require initialization. To resolve this, I added the following comment at the top of the affected files:
/* eslint-disable no-undef */
Additionally, there were some imported values that were not used; for these cases, I simply removed them.
Conclusion
Through my exploration of static analysis tools, I have gained a deeper understanding of their significance, particularly in collaborative projects. The primary goal of these tools is to facilitate teamwork and maintain high code quality, and I now appreciate how to effectively set up a project to integrate these essential tools from the outset.