Snippets

[AlanGreene]

npm scripts access to npm-specific environment variables, e.g. $npm_new_version for npm version command

"check-env": "node -e 'console.log(process.env)' | grep npm"

https://www.twilio.com/blog/npm-scripts

"demo": "echo \"Hello $npm_config_first $npm_config_last\""

npm run demo --last=Kundel --first=Dominik

git merge histories (e.g. importing existing projects into monorepo)

# Add an external repository as a remote
git remote add -f <external-repo-name> <external-repo-path>
# Merge commit history of a required branch
git merge --allow-unrelated-histories <external-repo-name>/<branch-name>
# files will be merged to root of repo so then need to move to appropriate place in e.g. `packages/`
# also create branch to track original repo to preserve history
git branch init/$package $package/master

[AlanGreene]

detect clamshell mode (tested on macOS 12.6)
ioreg -r -k AppleClamshellState -d 1 | grep AppleClamshellState | head -n1

[AlanGreene]

disable sleep on battery in clamshell mode:

pmset -g | grep hibernatemode (record this, was 3 when I checked)

sudo pmset -a sleep 0
sudo pmset -a hibernatemode 0
sudo pmset -a disablesleep 1

revert:

sudo pmset -a sleep 1
sudo pmset -a hibernatemode <original hibernatemode value | usually 3 on a MacBook>
sudo pmset -a disablesleep 0

may only need the disablesleep setting… (worked when testing on macOS 12.6 with 2021 16-inch M1 Max)

[AlanGreene]

# Delete a given line number in the known_hosts file.
knownrm() {
 re='^[0-9]+$'
 if ! [[ $1 =~ $re ]] ; then
   echo "error: line number missing" >&2;
 else
   sed -i '' "$1d" ~/.ssh/known_hosts
 fi
}

[AlanGreene]

You can also enable remote login on the command line:

sudo systemsetup -setremotelogin on

[AlanGreene]

GitHub Flavored Markdown - note / warning blocks

https://github.com/orgs/community/discussions/16925

> [!NOTE]  
> Highlights information that users should take into account, even when skimming.

Note

Highlights information that users should take into account, even when skimming.

> [!IMPORTANT]  
> Crucial information necessary for users to succeed.

Important

Crucial information necessary for users to succeed.

> [!WARNING]  
> Critical content demanding immediate user attention due to potential risks.

Warning

Critical content demanding immediate user attention due to potential risks.

• NOTE: the trailing whitespace at the end of the first line of each block is intentional

[AlanGreene]

Cypress - better CI logs

https://slides.com/bahmutov/fast-me?utm_source=substack&utm_medium=email#/20/2/0

// cypress.config.js
setupNodeEvents(on, config) {
  require('cypress-mochawesome-reporter/plugin')(on)
  require('cypress-terminal-report/src/installLogsPrinter')(on)
},
  
// spec or support file
require('cypress-mochawesome-reporter/register')
afterEach(() => {
  cy.wait(50, { log: false }).then(() => {
    cy.addTestContext(Cypress.TerminalReport.getLogs('txt'))
  })
})
require('cypress-terminal-report/src/installLogsCollector')()

Cypress test replay

https://currents.dev/posts/currents-cypress-replay-debugger
https://github.com/currents-dev/cypress-debugger

The plugin is free and open source. You can start using it today on your CI setup. When installed it will capture:

capture Cypress test execution steps
capture DOM snapshots for each step
capture browser console messages
capture browser the networks requests (HAR)

All this information will be dumped into a file that we can then load into a web player for replaying. The player is available at https://cypress-debugger.dev/

[AlanGreene]

50 most frequently updated files in past year:

git log --name-only --since=12.month --format=format: | egrep -v '^$' | sort | uniq -c | sort -nr | head -n50

[AlanGreene]

# sudo not required for some system commands
for command in mount umount sv pacman updatedb su shutdown poweroff reboot ; do
	alias $command="sudo $command"
done; unset command

[AlanGreene]

# Get week number
alias week='date +%V'

[AlanGreene]

# Highlight section titles in manual pages.
export LESS_TERMCAP_md="${yellow}";

[AlanGreene]

# `tre` is a shorthand for `tree` with hidden files and color enabled, ignoring
# the `.git` directory, listing directories first. The output gets piped into
# `less` with options to preserve color and line numbers, unless the output is
# small enough for one screen.
function tre() {
	tree -aC -I '.git|node_modules|bower_components' --dirsfirst "$@" | less -FRNX;
}

[AlanGreene]

Style XML to point users at RSS reader for example: https://jakearchibald.com/2025/making-xml-human-readable-without-xslt/

<?xml-stylesheet type="text/css" href="styles.css"?>

That said, if you just want to catch users that mistakenly land on some XML, you can get away with something like this:

:root {
  & > * {
    display: none;
  }

  &::before {
    content: 'Hi there! This is my RSS feed. '
      "It isn't meant to be human-readable…";
  }
}

Which is what I've done with my RSS feed.

[AlanGreene]

# Convert epoch to human readable (print current date if no args)
epoch() {
	local num=${1:--1}
	printf '%(%B %d, %Y %-I:%M:%S %p %Z)T\n' "$num"
}

[AlanGreene]

Using Node.js for platform-independent utils

# Platform-independent interfaces
interfaces() {
	node <<-EOF
	var os = require('os');
	var i = os.networkInterfaces();
	Object.keys(i).forEach(function(name) {
		i[name].forEach(function(int) {
			if (int.family === 'IPv4') {
				console.log('%s: %s', name, int.address);
			}
		});
	});
	EOF
}

# Calculate CPU load / Core Count
load() {
	node -p <<-EOF
	var os = require('os');
	var c = os.cpus().length;
	os.loadavg().map(function(l) {
		return (l/c).toFixed(2);
	}).join(' ');
	EOF
}

# Platform-independent memory usage
meminfo() {
	node <<-EOF
	var os = require('os');
	var free = os.freemem();
	var total = os.totalmem();
	var used = total - free;
	console.log('memory: %dmb / %dmb (%d%%)',
	    Math.round(used / 1024 / 1024),
	    Math.round(total / 1024 / 1024),
	    Math.round(used * 100 / total));
	EOF
}

[AlanGreene]

# print lines over X columns (defaults to 80)
over() {
	awk -v c="${1:-80}" 'length($0) > c {
		printf("%4d %s\n", NR, $0);
	}'
}