Anastasiia Hlushkova | Oct2025-1 | Module-Tools | Sprint-3 | Implement-shell-tools - #5

There is a subtle difference in behaviour for the line numbers, when using -n across multiple files:

$ cat -n sample-files/*.txt
    
     1	Once upon a time...
     1	There was a house made of gingerbread.
     1	It looked delicious.
     2	I was tempted to take a bite of it.
     3	But this seemed like a bad idea...
     4
     5	There's more to come, though...


$ node cat.js -n sample-files/*.txt

1	Once upon a time...
2	There was a house made of gingerbread.
3	It looked delicious.
4	I was tempted to take a bite of it.
5	But this seemed like a bad idea...
6
7	There's more to come, though...

I'm not too concerned about the formatting, but when running 'cat -n' it gives you the line numbers relative to each file, whereas in your implementation you are joining the file contents together first, and then adding in the line numbers

I fixed this by moving the lineNumber variable inside the file loop so it resets to 1 for each file. I also took the opportunity to match cat's formatting by right-aligning line numbers in a 6-character wide field using padStart(6). Thanks for reviewing!

Couple of things:

First when showing hidden files, ls also shows the routes to the current and parent directory (. and ..) i.e.:

$ ls -1 -a sample-files
.
..
.hidden.txt
1.txt
2.txt
3.txt
dir

$ node ls.js -1 -a sample-files
.
..
.hidden.txt
1.txt
2.txt
3.txt
dir

Secondly, it doesn't look like you support the -1 argument. For ls the difference between supplying and not is:

$ ls
README.md	ls.js		sample-files

$ ls -1
README.md
ls.js
sample-files

whereas yours always returns the filenames one per line.

Thanks for the feedback!

I've fixed both issues:

Added support for the -1 flag — now the output is printed in a single column only when this flag is provided, and defaults to a tab-separated format otherwise.
Updated the -a behavior to include . and .., matching the standard ls output.

Now the results align with the expected behavior for both -a and -1 options.

It looks like there's a bug in the line counting:

$ wc -l sample-files/*
       1 sample-files/1.txt
       1 sample-files/2.txt
       5 sample-files/3.txt
       7 total

$ node wc.js -l sample-files/*
2 sample-files/1.txt
2 sample-files/2.txt
6 sample-files/3.txt

It's because when you do data.split('\n') you also get an empty string afterwards because there's a '\n' at the end of the last line e.g. "Once upon a time...\n" => ['Once upon a time...', '' ].

wc also shows the option when flags are supplied, showing the total for the aspects selected, which yours isn't doing e.g.:

$ wc -l sample-files/*
       1 sample-files/1.txt
       1 sample-files/2.txt
       5 sample-files/3.txt
       7 total

Thanks for pointing this out!

You're absolutely right — the issue was caused by splitting on '\n', which adds an extra empty string when the file ends with a newline. I’ve fixed the line counting to handle this case correctly.

Also implemented the total count output when flags are used, so now it matches the behavior of wc.

Appreciate the detailed review!