Stuck on #IP1, /bin/cat not found on test environment

Challenges
1

I’m stuck on Stage #IP1

I’ve tried running on my local, “type cat” command works fine, but I cannot get it right in the test environment.

Here are my logs:

[tester::#MG5] Running tests for Stage #MG5 (The type builtin: executable files)
[tester::#MG5] [setup] export PATH=/tmp/quz:$PATH
[tester::#MG5] [setup] export PATH=/tmp/baz:$PATH
[tester::#MG5] [setup] PATH is now: /tmp/baz:/tmp/quz:/usr/local/sbin:...
[tester::#MG5] [setup] Available executables:
[tester::#MG5] [setup] - my_exe
[tester::#MG5] Running ./your_program.sh
[your-program] $ type cat
[your-program] cat: command not found
[tester::#MG5] ^ Line does not match expected value.
[tester::#MG5] Expected: "cat is /bin/cat"
[tester::#MG5] Received: "cat: command not found"
[your-program] $ 
[tester::#MG5] Assertion failed.
[tester::#MG5] Test failed

And here’s a snippet of my code:

 using System.Diagnostics;

namespace codecrafters_shell.CommandInterpreter;

public class CommandInterpreter : ICommandInterpreter
{
    private const string EchoCommand = "echo";
    private const string TypeCommand = "type";
    private const string ExitCommand = "exit";

    private const string PathEnvironmentVariable = "PATH";

    private static readonly HashSet<string> ValidCommands =
    [
        EchoCommand,
        TypeCommand,
        ExitCommand
    ];

    // The boolean return type is for indicating whether the shell should continue running.
    public bool InterpretCommand(string commandString)
    {
        var command = new Queue<string>(commandString.Split(' '));

        if (TryRunProgram(command)) return true;
        var action = command.Dequeue();

        if (action == ExitCommand)
            //Ignore if it is exit 0 or not for now
            return false; // Indicates that the shell should stop running.
        if (action == EchoCommand)
        {
            ExecuteEchoCommand(command);
            return true;
        }

        if (action == TypeCommand)
        {
            ExecuteTypeCommand(command);
            return true;
        }

        Console.WriteLine($"{action}: command not found");
        return true;
    }

    private void ExecuteTypeCommand(Queue<string> command)
    {
        if (command.Count == 0)
        {
            Console.WriteLine("No command provided for type command.");
            return;
        }

        var action = command.Dequeue();
        if (ValidCommands.Contains(action))
        {
            Console.WriteLine($"{action} is a shell builtin");

            return;
        }

        var paths = GetEnvironmentPaths(action);
        foreach (var path in paths)
        {
            if (File.Exists(path))
            {
                Console.WriteLine($"{action} is {path}");
                return;
            }
        }


        Console.WriteLine($"{action}: not found");
    }

...

* List item

private List<string> GetEnvironmentPaths(string fileName)
    {
        var pathEnvironmentVariable = Environment.GetEnvironmentVariable(PathEnvironmentVariable);
        var paths = pathEnvironmentVariable?.Split(':').ToList() ?? [];
        return paths.Distinct().Select(path => Path.Combine(path, fileName)).ToList();
    }
}

I have uploaded the whole project to github in case you want to run it: GitHub - leonCTL12/CodeCrafterShell

4

Hey @leonCTL12, looks like your shell isn’t running type as the command:

image
image1628×668 198 KB

This is happening because TryRunProgram dequeues the command but doesn’t put it back:

image
image1148×1218 96.4 KB

Let me know if you’d like further clarification!

6

Thank you so much for your help. I indeed overlooked the fact that the command queue is passed by reference instead of value

The reason why I got it right in the local environment because I actually ran “type” as an executable instead of a command. And in the test environment, there is no “type” executable. That’s why it exits the TryRunProgram() with false and continues to look for the matching case for “cat” command.

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