'file name differs from already included file name only in casing' on relative path with same casing

typescript

best-practices

file-management

typescript-configuration

byAnton Shumikhin·Jan 3, 2025

// Correct file import case:
import CorrectCase from './FileExactCase'; // Precise as a German train schedule

// Common mistake:
import incorrectcase from './fileexactcase'; // This could lead to a casing catastrophe!

// Tip: Use the exact case for file names in your imports. 
// Missteps in case handling could make your code go BOOM in 
// case-sensitive environments like Linux or during builds with tools like Webpack.
// Solution: Spruce it up! Align the case in your import statements 
// with the actual file names.

Ensure your import statements' casing matches the actual file names—especially crucial when dealing with case-sensitive systems.

What Makes Case Important

The OS Factor

While Windows tends to be very forgiving when it comes to file name casing, stricter systems like Linux aren't. They treat SomeFile.ts and someFile.ts as two completely different entities.

TypeScript Configuration to the Rescue

Within your tsconfig.json, enable forceConsistentCasingInFileNames.

{
  "compilerOptions": {
    "forceConsistentCasingInFileNames": true 
  }
}

With this turned on, TypeScript will throw an error if your imports don't perfectly match the case of the actual files.

Choosing Names Wisely

For effective file management, remember:

Consistency is king: Stick to a naming convention, like camelCase or PascalCase, and ensure all files follow suit.
Mirror your imports: Make sure the file name casing in your import paths aligns with the actual file names.

Handling Renaming and Cache Issues

Sometimes, a simple rename operation might not be enough. Fret not:

Try renaming the file twice: For instance, rename SomeFile.ts to somefile.ts and then back to SomeFile.ts.
Or, you can restart the TypeScript server within your development environment.

Cross-Platform Pitfalls and How to Avoid Them

To avoid stepping on cross-platform landmines:

Regularly test your code on different operating systems.
Keep in mind that build tools like Webpack might act differently based on file casing.

IDEs and Their Role in File Management

Modern IDEs like Visual Studio Code are your faithful allies. They can:

Prompt you when there's a casing mismatch.
Rename your files.

Consistent is Strong: forceConsistentCasingInFileNames

You may be tempted to disable forceConsistentCasingInFileNames for a quick fix. However, I advise against doing so. Using a consistent casing approach ensures your code stays robust across different environments.

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