Linux CoreUtils developers break "ls"

I've been running Linux Mint 18.2 on my desktop for the last few years, and I've been pretty happy with it. However, it's based on Ubuntu 16.04, which is getting kinda long in the tooth. Specifically I found I couldn't compile the version of wxformbuilder I need for my KiCad work because it requires a newer compiler than is available for Ubuntu 16.04.

So I decided to upgrade my systems to something based on the Ubuntu 18.04 release, which is the latest long-term support release. Everything seemed to be going well until I started tried to list files in a directory. The first thing I found is that the sorting in "ls" now ignores underscores in file names.

For example, I was looking for a file named "pcb_parser.cpp" in the file listing:

pcb_layer_widget.cpp
pcb_legacy_draw_utils.cpp
pcb_netlist.cpp
pcbnew_config.cpp
pcbnew.cpp
pcbnew_printout.cpp

When I reached the file named "pcbnew_config.cpp" I figured I must have missed it and scanned the list from the top again. Confused, I looked more methodically and found the names continue:

pcbnew.cpp
pcbnew_printout.cpp
pcb_origin_transform.cpp
pcb_painter.cpp
pcb_parser.cpp
pcbplot.cpp
pcb_plot_params.cpp

What is this madness? This doesn't look like a sorted list to me.

As best I can tell, the people who maintain the core apps (like "ls") have decided to "improve" this fundamental application by changing the default sort algorithm to so-called "Natural Sorting". This means that if you have files with names from "file1" to "file20", you'll see "file10" after "file9" rather than after "file1". That's kind of a nifty trick, but the change in behavior is extremely confusing to those of us who have worked with Linux, Unix, and Unix-like systems for decades.

Apparently they also decided that underscores and spaces don't really count as a character, and file names are sorted as if they don't exist. Except when they do, because "file 13" will be sorted just before "file_13" which will come just before "file13", but after "file12". Clear?

That's all very nice. Except they decided to make "Natural Sorting" the new default behavior instead of an option you can choose. The docs say that the "-v" option turns on this behavior, but by trial and error I discovered that the "-v" option actually turns it OFF. Quite frankly, the unexpected change to a 40 year-old behavior is both unwanted and alarming.

Then I discovered something else: if you have spaces in a file name, "ls" now adds single-quote marks around the name. Like this:

pcb_plot_params.cpp
'pcb plumber.cpp'
pcb_screen.cpp

But only if it's displaying on a terminal, so sometimes you see them and sometimes you don't. Again, this is the new default behavior.

You can disable this by adding either "-N" or "--literal" to the "ls" command, or by setting an environment variable in your .bashrc file:

QUOTING_STYLE=literal

But to find this you have to go looking for this in email threads and bug reports, because it's seemingly not documented elsewhere.

Many people have objected to these changes, but the CoreUtils developers don't care. I guess they want to leave their marks on the world, even if they're black marks.