Why does escaping spaces with backslash fail to work in some cases?

[Flimm]

I'm using Ghostty 1.0.1 on Ubuntu 24.10 with the fish shell. These commands work as expected:

$ echo 'Hello world' > 'one two.txt'
$ cat one\ two.txt
Hello world

I've verified using other methods that a file named one two.txt was created, and that it contains the expected content.

Now, if I type this, it fails to work:

$ cat one\ two.txt | head
cat: one: No such file or directory
cat: two.txt: No such file or directory

Now, suddenly, the backslash space no longer seems to function as intended. cat seems to see two arguments one and two.txt, rather than just one argument one two.txt. I had to pipe the output to something else for the problem to manifest itself. I'm using backslash space, because that is what the shell autocompletes to.

If I change my shell from Fish to Bash, I no longer experience this problem. If I use GNOME Terminal instead of Ghostty, I no longer experience this problem, even when using Fish. My mistake. I experience this issue even on GNOME Terminal. So I don't think Ghostty is the problem here, I think it is Fish. At this point, I would delete this discussion if I could.

[00-kat]

That's a shell issue, not a terminal issue. I don't have this issue on Fish (version 3.7.1) though.