wc.NET: A Unix-like word count tool for Windows

This project aims to recreate the Unix wc utility for Windows as part of the Coding Challenges series by John Crickett.
The key objectives of this project are (for more details visit here):

• Achieve support for the following commands: -c, -l, -w, -m.
• Develop a robust and efficient wc implementation.
• Ensure the application is modular and can accommodate future enhancements with minimal code changes.
• Adhere to best practices and coding standards, including SOLID principles, design patterns, and TDD to maintain code quality.

Technical Stack

• C# with .NET 8.0
• LightResults
• Xunit
• NSubstitute
• FluentAssertions

Features

Source Code

• Byte count (-c): Counts the number of bytes in a file.
• Line count (-l): Counts the number of lines in a file.
• Word count (-w): Counts the number of words in a file.
• Character count (-m): Counts the number of characters in a file. If the current locale does not support multibyte characters this will match the -c option.
• No command/Default option: It is an equivalent to -c, -l, and -w options.
• .editorconfig: Enforces consistent coding styles and formatting across the project, ensuring adherence to best practices and reducing code review overhead.
• Flexible dependency injection: Utilizes .NET 8 Dependency Injection with Keyed Services for scalable and maintainable command resolution.
• Command pattern: Implements the Command Pattern for handling different command-line arguments, ensuring flexibility and adherence to SOLID principles.
• Command-line arguments parser: Includes a built-in parser for handling command-line inputs.
• Template method pattern: Incorporates the Template Method Pattern to share common execution logic across commands.

Tests

• End-to-End tests: Test the application as a whole, ensuring that it behaves as expected in real-world scenarios.
• Integration tests: Test how different parts of the application work together.
• Unit tests: Comprehensive unit tests for each component, ensuring code reliability.
• Benchmarks: Performance testing to ensure the tool operates efficiently even with large files.

Build the solution

Run the application

Project structure

vp-coding-challenge-wcnet/
├── src/
│   └── WCNet/
|       ├── VP.CodingChallenges.WCNet.csproj    #.csproj file
│       ├── Attributes/                         # Custom attributes like CommandKeyAttribute
│       ├── CommandResolvers/                   # Command resolver classes
│       ├── CommandHandlers/                    # CommandHandler and base classes
│       ├── Commands/                           # Command implementations (e.g., ByteCountCommand)
│       ├── Models/                             # Core models like Command
│       ├── appsettings.json                    # Configuration for the application
|       └── Program.cs                          # Entry point of the application
└── test/
|   └── WCNet/
|       └── Tests
|           └── VP.CodingChallenges.WCNet.Tests.csproj    #.csproj file
|               ├── E2ETests
|               ├── IntegrationTests
|               └── UnitTests
|       └── Benchmarks
|           └── VP.CodingChallenges.WCNet.Benchmarks.csproj    #.csproj file

How to?

Add a new command

• Create a class in Commands > Concrete directory/folder, with prefix Command and add CommandKeyAttribute to it.

  [CommandKey("x")]
  internal sealed class TestCommand : ICommand
  {
  	public String Execute (String filepath) => throw new NotImplementedException();
  }
  

• Add the same command-key (x in this case) in ParserOptions of appsettings.json as follows:

  //before
  {
  	"ParserOptions": {
    	"CommandExpression": "^(-[clwm])"
  	}
    }
  
  //after
  {
  	"ParserOptions": {
  		"CommandExpression": "^(-[clwmx])"
  	}
  }
  

Run your newly added command

• Modify launchSettings.json as follows:

  "commandLineArgs": "-<your_command-key> <filename>.txt"
  

• Build and run the application.