rubocop and rufo

I’ve been writing in the Ruby language since sometime in 2002, but if I was looking for a job, I don’t know enough to call myself a ruby programmer. I don’t know rails or anything of the other cool things people do with ruby. I’ve learned to use gems, but haven’t bothered to learn how to write them myself.

But I’m not opposed to learning. I just haven’t gotten around to it yet.

Or so I thought. Then I ran into rubocop, which is a sort of linter and style cop. Those can be helpful, so I thought I’d give it a try. And it’s mostly good. Except it’s opinionated, and some of their opinions are wrong. For example:

  • the indentation should be four spaces, not two as they suggest
  • parallel assignment is the bomb, despite what they say
  • I use double quotes (") pretty much everywhere I’m not forced to use single quotes ('). They want to save time for the compiler, I guess.
  • You need space inside parentheses (although I will grant the extra whitespace is less important with syntax highlighting than without it).
  • And if I’m declaring a RE that’s so complicated I’m using /x flag, then don’t tell me to use /.../ instead of %r<...>.
  • And speaking of which, go ahead and use $1 and $' when retrieving the results of an RE match. (In moderation.) Honestly, this is a tie. Go ahead and use named groups if you want to.

But you can’t fight city hall. If some younglings want to make Ruby over in the style of Python, well, that’s a crying shame. Ruby is supposed to occupy the perfect spot between Perl and Python. But these kids today! If they’re on your lawn, you might as well go along with their misguided project. And that brings us to rufo, the ruby reformatter. You can use it to do like 10% of the things that rubocop whinges about.

Setting Up a Mac

Fixing mouse scroll direction, key bindings, setting up Exposé spaces, etc.

Installing Keynote, Numbers, and Pages plus any software previously purchased from the App Store.

Installing replacement browsers: Chrome, Firefox, and Brave, along with Xee and iTerm2 and Skim.

Installing MacPorts, then software starting with ImageMagick. Imagemagick because it’s a good test of everything working properly.

$ sudo port install imagemagick +graphviz -x11

Then adding some of my favorite utilities

$ sudo port install antiword bat colordiff exiftool jhead lame sox tree xz

$ sudo port install ffmpeg -x11

$ sudo port install nnn ranger

Then install software development languages: go, rust, and ruby. Follow them with some CLI utilities written in those languages:

$ cargo install broot cw du-dust dutree exa fd hexyl \
just lsd pastel ripgrep sd

$ go get -u github.com/gokcehan/lf

installing eyeD3

I keep thinking I should learn the basics of Python programming. But I never seem to get around to it.

Today I needed to know how to install a program written in Python, because Homebrew used to include eyeD3 and today it didn’t. Here’s what I ended up doing:

$ sudo easy_install pip   # because pip isn’t installed

$ sudo pip install eyeD3

then it says that won’t work because libmagic isn’t installed. But fortunately, Homebrew provides that (whatever it is). So try again:

$ brew install libmagic

$ sudo pip install eyeD3

P.S. eyeD3 is the best command-line ID3 tag editor I’ve found. It is the only thing I’ve found that allows you to install album art from the command line. (See my earlier post.)

 

Mini Magick

I just discovered MiniMagick. It is exactly what I was looking for in a ruby-language wrapper for ImageMagick.

I’ve been using ImageMagick forever. Like, more than 20 years foreer. Maybe 30 years;  I don’t know when it was first developed, or how old it was when I discovered it.

Some of the time, I use ImageMagick from the command line: just convert a file or montage a couple of them, or whatever. But sometimes, I do the same three things to an image and expect to do it over and over again for multiple images, I’ll write a shell script.

Writing shell scripts is hard. (Like, do you use trap? Of course you don’t.)

Writing Ruby is easy. But the only Ruby wrapper for ImageMagick I knew about was RMagick, which is big and complex and the first couple of times I tried to use it I had build problems (this was back before gems and github).

So there I was. Use bash and keep it simple, or use ruby with some crazy backtick `convert foo.png foo.jpg` shell escape there instead of doing it right.

But MiniMagick is just a well-designed wrapper around those backticks. Kudos!

iMac configuration

I mentioned previously how I’ve rehabilitated the 10-year old iMac. Today, I’ve been setting up the software environment.

First, I transferred my iTunes library over to the new computer.

Then I installed some non-Safari browsers: Chrome, Firefox, and Brave.

Then I set up Homebrew, and after that, ruby:

$ brew install openssl # various messages because Apple doesn’t like openssl
$ brew install sqlite pcre
$ git clone git://github.com/sstephenson/rbenv.git ~/.rbenv
$ git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
$ rbenv install -l
$ rbenv install 2.4.1 # (as of May 19, 2017)
$ hash -r # rehash your environment

Things I Did After Installing 17.04

Here in one place is my list of things to do after installing a new operating system.

$ sudo apt update
$ sudo apt upgrade
$ sudo apt install ssh

Then try to ssh into the computer. If needed, apply the fix to Zeroconf / Avahi / NSSwitch.conf.

Next:

$ sudo apt install git
$ sudo apt install colordiff
$ sudo apt install libreadline-dev
$ sudo apt install vim vim-gtk3
$ sudo sudo apt-get --purge --reinstall install ttf-mscorefonts-installer

Then I got things ready for ruby. I prefer rbenv:

$ sudo apt install libssl-dev zlib1g-dev # needed for ruby
$ sudo apt install sqlite3 sqlite3-pcre
$ cd ; git clone git://github.com/sstephenson/rbenv.git .rbenv
$ git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
$ rbenv install -l
$ rbenv install 2.4.1 # (as of April 28, 2017)
$ hash -r # rehash your environment

P.S. if later on you want a later version of ruby, the way you update the list of installable ruby’s is:

$ cd ~/.rbenv/plugins/ruby-build ; git pull

Then use gdebi to install Google Chrome.

$ sudo apt install gdebi
$ apt install chromium-browser chromium-codecs-ffmpeg chromium-codecs-ffmpeg-extra
$ apt install telegram-desktop

I’d love to be able to pre-populate Dropbox from a local backup when I setup a new computer. But I’m not smart enough, I guess.

$ sudo apt install antiword wv jhead
$ sudo apt install imagemagick poppler-utils

Tech Links

LinuxUser (UK): Create a NAS box from spare parts.

Ars: Intel’s Broadwell mini-PC. I love the form factor. But then, I’ve owned three Mac Minis.

I keep thinking I should learn the R language. Of course, I used to think that about GnuPlot.

HowToForge: Installing Git and Using GitHub on Ubuntu.

GSoC: SciRuby. There’s a program I’d love to rewrite 20 years later using a high-level language to do the Fast Fourier Transforms. I’m not sure what I’d use for the GUI.

Web UpD8: Install the official Telegram client for Linux.

 

 

 

 

rbenv notes

I used to use rvm to manage my ruby environment, but the latest hotness seems to be rbenv. Here are some tips about using it. They’re aimed at me, because by the next time I need to use it, I’ll have forgotten. But you can read them too:

One of the things you want is rbenv-build:

Installing ruby-build as an rbenv plugin will give you access to the rbenv install command.

$ mkdir -p ~/.rbenv/plugins
$ cd ~/.rbenv/plugins
$ git clone git://github.com/sstephenson/ruby-build.git

(Note the assumption you’re using git. I don’t know what people who prefer mercurial are supposed to do.)

This will install the latest development version of ruby-build into the ~/.rbenv/plugins/ruby-build directory. From that directory, you can check out a specific release tag. To update ruby-build, run git pull to download the latest changes.

But that won’t work with Mountain Lion. So you’ll need a version of ruby that can be built with clang.

$ rbenv install 1.9.3-p125

Ruby and Mac OS X Lion

When Apple switched from GCC to LLVM in Xcode 4.2, they made it significantly more difficult for me to run ruby 1.9.2. (What are the odds this will get easier with Mountain Lion?)

I was using rbenv and its rbenv-build plugin to install ruby 1.9.2 and it told me this:

$ rbenv install 1.9.2-p320

ERROR: This package must be compiled with GCC, but ruby-build couldn't
find a suitable `gcc` executable on your system. Please install GCC
and try again.

DETAILS: Apple no longer includes the official GCC compiler with Xcode
as of version 4.2. Instead, the `gcc` executable is a symlink to
`llvm-gcc`, a modified version of GCC which outputs LLVM bytecode.

For most programs the `llvm-gcc` compiler works fine. However,
versions of Ruby older than 1.9.3-p125 are incompatible with
`llvm-gcc`. To build older versions of Ruby you must have the official
GCC compiler installed on your system.

TO FIX THE PROBLEM: Install the official GCC compiler using these
packages: https://github.com/kennethreitz/osx-gcc-installer/downloads

You will need to install the official GCC compiler to build older
versions of Ruby even if you have installed Apple's Command Line Tools
for Xcode package. The Command Line Tools for Xcode package only
includes `llvm-gcc`.

Note: when you install that, it doesn’t (appear to) provide an uninstaller. Instead it says this:

If something doesn’t work as expected, feel free to install Xcode over this installation.

Once installed, you can remove Xcode completely with the following:

sudo /Developer/Library/uninstall-devtools –mode=all

Bummer for me, huh? Mercifully, the GCC installation package doesn’t mess up the llvm-gcc link in /usr/bin/gcc. But that means when I do the ruby build, I need to add:

export CC=/usr/bin/gcc-4.2