...notice that the records you create are not deleted and will bleed into your specs the next time you run them. You probably have DatabaseCleaner configured to take care of...

...not bloating your test database with old records: RSpec.configure do |config| config.before(:suite) do DatabaseCleaner.clean_with(:deletion) end config.before(:each) do DatabaseCleaner.strategy = :transaction end config.before(:each, transaction: false) do DatabaseCleaner.strategy...

makandracards.com

...bug) and want to use git bisect to find out when it was introduced? Smart kid. If you have a shell command ready to reveal if your current state is...

...other hand will use the return value of that call to decide if the state is good or bad. First, start bisecting git bisect start Then tell git which revisions...

...the commit which was deployed. If you want to know the currently deployed release, simply SSH to a server and view that file. $ cat /var/www/my-project/current/REVISION cf8734ece3938fc67262ad5e0d4336f820689307 Capistrano task

...application is deployed to multiple servers, you probably want to see a result for all of them. Here is a Capistrano task that checks all servers with the :app role...

...if you do not know. How are cookies transferred between your browser and the server? Open the development tools in your browser for this page. Can you find the cookies...

...your browser stores for makandracards? In the network tab, can you see how the cookies are transferred to or from the server? Can you log yourself out by manipulating a...

github.com

...Mocking the time zone You can't really change the local time zone of the Selenium-controlled browser. What you can do is change the time zone of the process...

...setting this from an individual test, since you don't know whether or not the Selenium-controlled browser has already launched. Note that we have only tested this with a...

github.com

Capybara-screenshot can automatically save screenshots and the HTML for failed Capybara tests in Cucumber, RSpec or Minitest. Requires Capybara-Webkit, Selenium or poltergeist for making screenshots. Screenshots are saved...

...into $APPLICATION_ROOT/tmp/capybara. Manually saving a page Additionally you can trigger the same behavior manually from the test using Capybara::Session#save_and_open_page and Capybara::Session#save_screenshot...

Geordi provides a pretty neat way to generate beautiful commit messages according to your stories in Linear: geordi commit Geordi reads from a .geordi.yml file inside your repo and connects...

...to Linear to list started and finished stories with their title. Choosing one of them generates a commit message including id and title from Linear app and a link to...

linux.die.net

...files. Those can be used to apply to a different repository [1] or by someone else (e.g. sent when sent to them via e-mail). Creating a patch in git...

...changes and commit them. Run git format-patch COMMIT_REFERENCE to convert all commits since the referenced commit (not including it) into patch files. For example, let's say you...

I recently noticed a new kind of flaky tests on the slow free tier GitHub Action runners: Integration tests were running on smaller screen sizes than specified in the device...

...metrics. The root cause was the use of Selenium's page.driver.resize_window_to methods, which by design does not block until the resizing process has settled: We discussed this issue...

...been released just a few days ago, allowing us to use Webpack 4. I successfully upgraded an existing real-world Webpack 3 application. Below are notes on everything that I...

Note that we prefer not using the Rails asset pipeline at all and serving all assets through Webpack for the sake of consistency. Preparations Remove version locks in Gemfile...

developer.mozilla.org

You can do so much more than console.log(...)! See the attached link for a great breakdown of what the developer console can give you. Some of my favorites: console.log takes...

E.g. console.log("Current string:", string, "Current number:", 12) Your output can have hyperlinks to Javascript objects E.g. console.log("Check out the current %o, it's great", location)

Sometimes you need to remove high Unicode characters from a string, so all characters have a code point between 0 and 127. The remaining 7-bit-encoded characters ("Low-ASCII...

...can be transported in most strings where escaping is impossible or would be visually jarrring. Note Transliteration this will change the string. If you need to preserve the exact string...

github.com

...default it allows only accessing visible elements -- when you are using a driver that supports it (e.g. Selenium, not the default Rack::Test driver). Consider the following HTML: One

...true) or find(..., visible: :visible). Note that you could change the default behavior by setting the ignore_hidden_elements config option. However, ignoring invisible elements is a useful default.

...Learn to create test data effectively using factories. Decouple tests by having each test start with an empty database and create only the records needed for the test. Learn

...with every test. In our experience the use of fixtures can make a test suite hard to work with. In any non-trivial test suite there will be thousands of...

...library => Google Drive) CLI tricks every developer should know Install the tldr tool using sudo apt install tldr. You can then get usage examples for every console command, e.g. tldr...

...ssh to get examples for the ssh command. (If there are no entries, run tldr -u and try again) Exercises Basic commands Experiment and do something useful with the following...

...want to be in there. In order to reduce the chance to accidentally commit something you didn't intend, review your changes before committing. My preferred way of doing this...

...paths (including new files), but not their contents git add -p Git will now show you all your changes in small chunks and ask you in an interactive mode whether...

github.com

...a global variable in Rails? Ugh, that's the worst. If you need global state, you've probably reached for Thread.current. When you're using Thread.current, you must make sure...

...yourself or your cached data will stay in Thread.current. For Sidekiq, you can use request_store-sidekiq. Cronjobs are unaffected, as a new process is created each time...

rubydoc.info

CarrierWave comes with some RSpec matchers which will make testing more comfortable. Let's say you have an Uploader like this: class MyUploader < CarrierWave::Uploader::Base include CarrierWave::MiniMagick

...different versions of your uploaded files: version :small do process resize_to_fill: [100, 100] end version :medium do process resize_to_fit: [200, nil] end version :large do

...or ::1 (IPv6) can only be reached from your own PC: Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port Process tcp LISTEN...

...address 0.0.0.0 can be reached from other PCs on your network: Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port Process tcp LISTEN...

Learn to treat files as an ActiveRecord attribute type, like :string or :integer Research Look at the README for the carrierwave gem Read about Common mistakes when storing file...

...the form where we can also fill in title, year, etc. On the movie show view, render a poster version that is 400 pixel wide, with a height that respects...

When your Rails application server raises error, Capybara will fail your test when it clears the session after the last step. The effect is a test that passes all steps...

...behavior will help you to detect and fix errors in your application code. However, sometimes your application will explode with an error outside your control. Two examples: A JavaScript library...

...just barely wider than the container it should fit into, and it wraps a single word to a new line and it's not really pretty? Cry no more, for...

...in some browsers. When browsers encounter a text-wrapping element with text-wrap: balance style, they will try breaking to a new line sooner, if it balances out the width...

...tough challenge. To get more detailed insights consider using the rack-mini-profiler gem. Setup with Unpoly Add the following gems: group :development do gem 'memory_profiler' gem 'rack-mini...

If you have slow views (Haml/Partials can be slow), consider caching them. Remove code & sql-queries that are not needed to render the page. Calling to_a blindly on...

guides.rubyonrails.org

ActiveRecord offers an explain method similar to using EXPLAIN SQL statements on the database. However, this approach will explain all queries for the given scope which may include joins or...

Output will resemble your database's EXPLAIN style. For example, it looks like this on MySQL: User.where(id: 1).includes(:articles).explain EXPLAIN for: SELECT `users`.* FROM `users`  WHERE...