Today's tip of the day is a follow up from something I learned at
this year's Polyglot UnConference -- how
select with the Bash shell for interactive goodness.
At Polyglot I saw an example that looked like this:
select x in * ; do stat $x; done
Try this (go to a terminal and in the bash shell type it verbatim). Go ahead, I'll wait.
Did that? Cool, so as you saw the
select keyword is this way of interactively selecting
items from a glob with bash. In that above example, it allowed you to
stat a file you
Today I found a practical application of this: interactively deleting untracked files from a checked out Git repo.
My scenario: I was working on a future blog post and had created a handful of image files in the current directory. This isn't uncommon: I'll often get a single image that I want to use for something like the OpenGraph summary image for a post, and then I edit it via ImageMagick to resize it, change a background to transparent, etc, and then I run it through Crunch to shrink it down.
Today I found that after getting the final image I wanted, a
git status showed a number of
untracked files I didn't care about:
$ git status On branch codependentcodr/ch202/vscode-python-debugging-unit-tests-tasks Untracked files: (use "git add <file>..." to include in what will be committed) content/python-and-vs-code-part1.md content/static/imgs/vscode141.png content/static/imgs/vscodeAndPython.png content/static/imgs/vscodelogo-crunch.png content/static/imgs/vscodelogo.png nothing added to commit but untracked files present (use "git add" to track)
The only file I wanted from
vscodeAndPython.png, all the other stuff in
content/static/imgs was junk that could be deleted. I could manually delete
each one, typing the full filename each time, or I could save some keystrokes by
select and a little command-line fu:
select x in git status --porcelain | tr -d \?\?; do rm $x ; done
git status --porcelain just spits out the filenames from a
(no header/footer, extra stuff), and
tr -d \?\? removes the leading
prepended to any filename that is untracked. The
select iterates over each file
matched by this command in an interactive way, and then the
do rm $x removes whatever
file I select. This allowed me to interactively delete files that were untracked:
$ select x in `git status --porcelain | tr -d \?\?`; do rm $x ; done 1) content/python-and-vs-code-part1.md 4) content/static/imgs/vscodelogo-crunch.png 2) content/static/imgs/vscode141.png 5) content/static/imgs/vscodelogo.png 3) content/static/imgs/vscodeAndPython.png #? 2 #? 4 #? 5 $ git status On branch codependentcodr/ch202/vscode-python-debugging-unit-tests-tasks Untracked files: (use "git add <file>..." to include in what will be committed) content/python-and-vs-code-part1.md content/static/imgs/vscodeAndPython.png nothing added to commit but untracked files present (use "git add" to track)
I thought this was pretty cool, next time you find yourself wanting to choose from
a number of files on the command line, think about
Ok: I realize I could've just added the md file & the image I wanted to git and then deleted all untracked files, but would that have been as interesting as this blog post? I think not.