...can be especially painful when external code (read: gems) uses const_defined? to look something up and gets different results on different Rubies. Consider this: module Foo FOO = 42
end On Ruby 1.8, Bar won't have FOO defined as a constant since that's (even though it's accessible): 1.8.7 > Foo.const_defined? :FOO => true 1.8.7 > Bar.const_defined...
...capistrano_colors' end It's possible you need to do a bundle update net-ssh to get things running. Now double check that all your custom hooks are actually still...
...called. One candidate might be an after deploy:symlink hook that has been renamed into after deploy:create_symlink. I also suggest to put a safeguard into your deploy.rb that...
ZSH is an alternative command line shell that includes some features like spelling correction, cd automation, better theme, and plugin support. You can replace Bash with ZSH like following:
...apt-get install zsh Setting ZSH as default login shell sudo usermod -s /usr/bin/zsh $(whoami) Opening a new terminal window will show you a dialog where you can configure your...
...and a damaged reputation. Deploy Ruby with confidence knowing you're using the most secure, enterprise-grade builds for the platforms that power your business. You'll get priority access...
...fail-safe Ruby for business applications, but don't require advanced features like indemnification or site-wide licensing. Business Edition customers trust ActiveState's guaranteed technical support and regular fixes...
...association. For example you can put the blank form on top with the following snippet: actors = movie.actors actors.build actors.unshift(actors.pop(1)) # won't work with Rails 4+ Because build_for...
...one-to-many association collection object you only have to reorder the collection objects. Sorting with Rails 3+ = form.fields_for :children, @parent.children.sort_by(&:name) do |fieldsform...
...OPTS="--no-tcmalloc" rbenv install, but that would disable tcmalloc. Doing that, you might still encounter issues with ossl_ssl.c -- which is where I switched to the patched solution above...
...without_callbacks. There is no such thing in vanilla Rails 3. There is a gem sneaky-save that restores the missing functionality with a #sneaky_save method...
Table Of Contents Flexbox wrapping Spacing Long content Prevent an image from being stretched or compressed Lock scroll chaining CSS variable fallback Using fixed width or height...
...The fixed height The fixed width Forgetting background-repeat Vertical media queries Using justify-content: space-between Text over images Be careful with fixed values in a CSS grid
String#indent is not a standard Ruby method. When you use it, be sure to know where this method comes from. Many Gems shamelessly define this method for internal usage...
...and you'll never know when it may be removed (since it's usually not part of the Gem's API). Unless you're using Rails 4 (which brings String...
...both column name and value are coming from user input and need to be sanitized. Unfortunately this works in SQLite but does not in MySQL: named_scope :filter, lambda { |attribute...
{ :conditions => [ 'articles.? = ?', attribute, value ] } } The solution is to use sanitize_sql_array like this: named_scope :filter, lambda { |attribute, value| { :conditions => sanitize_sql_array([ "`articles`.`%s` = '%s'", attribute, value...
...it's likely that your cucumber.yml is just fine but not your rerun.txt.\ This sometimes happens when running multiple Cucumber workers with parallel_tests that write into rerun.txt simultaneously -- ending...
...Just remove it and you are good to go again: rm rerun.txt Another possible solution is to have one rerun file per worker for which you'd need to modify...
In rare cases you might need something like form_for (for using form builder methods on the resulting block element) but without the surrounding form. One such case would be...
...updating some of a form's fields via XHR. You can simply use Rails' fields_for to do things like this in your views (HAML here): - fields_for @user do...
Back in the old days, we couldn't do something like that: .foo { position: absolute; bottom: 0; /* This was bad: */ left: 10px; right: 10px; } Why? Because IE5 and IE6 (which...
...then) failed horribly trying to render it. I've now checked if this is still an issue with any browser that's not from the stone age. \
...because a printer's resolution is usually much higher than that of a computer screen. If an image absolutely must look awesome when printed, a solution is to embed the...
...image in much higher solution than needed (e.g. four times the horizontal resolution), then scale it down to the desired width using CSS. Note that this will slightly alter the...
Restricting access to cookies is essential for security in many web apps. For example, the session ID, the secret token used to identify a particular session, is typically stored in...
...a cookie. Cookies have several important settings. Previously, I discussed the secure flag. This time, let’s dive into the cookie domain. The cookie domain is an important security feature...
...variations' was not found; perhaps you misspelled it? I just was hunting down a strange error with this model: class Model placeholder = 'variations' has_many placeholder nested_scope :verbose, :include...
...work (the latter returned [ :some_association, 'variations' ]). Eventually, the quotes led me to the solution: I had to write has_many placeholder.to_sym. When Rails can't find an association...
...hard to achieve), because it is no actual "integration testing". If you use this step, know what you are doing. Destroying a record with Capybara is not as easy as...
...user, method: :delete), because RackTest's visit can only perform GET requests. With this step you can destroy a records using either Selenium or RackTest. Example: When I destroy that...
Capybara will match elements outside of a page's tag. For example, the step definitions below match nodes in a page's : Then /^my browser should auto-discover the "([^"]*)" feed...
page.should have_css( 'head link' + '[rel="alternate"]' + "[href='http://www.example.com/#{slug}/feed.rss']" + '[title="RSS feed (all cards)"]' + '[type="application/rss+xml"]', visible: false ) end Then /^my browser should...
When you create e.g. a sidebar box that contains headlines and paragraphs, the final paragraph's margin in that box will create an undesired 'bottom padding' inside that box.
...is a Sass mixin that you can apply to such boxes. It makes the last child's bottom margin disappear: =hide_last_margin >*:last-child margin-bottom: 0
...default Ruby, RubyMine will give you incorrect inspections, for example.\ Here is how to switch which Ruby you use in RubyMine. File → Settings (Or press Ctrl+Alt+S)
...SDK and Gems" from the left pane Switch your "Ruby interpreter". Though it may seem you are changing a global setting here, this is in fact a per-project setting...
change_association :parent, class_name: 'Parent::AsForm', inverse_of: :children end When saving a Parent::AsForm record with nested Child::AsForm records, the children will not be saved...
...case where you override the association with has_many :children,...
...and belongs_to :parent, .... Solution This can be fixed with appending autosave: true to the Parent model: class Parent < ApplicationRecord...
find . -cnewer other_file This can be used to check against a specific timestamp, too. This is how you check for all files modified today (since...
...the current bash's PID so you will get some file like /tmp/12345 that stays the same for the current shell. This allows you to check against this file again...
...you want to manually check if e-mail delivery works on a machine by sending an e-mail you can run the following: mail -s Test someone@example.com < /dev/null
...send an empty e-mail with "Test" as its subject to someone@example.com. If you want it to contain a message body, call mail -s Test someone@example.com only; the mail application...
Adobe no longer supports their PDF reader on Linux and the official page does not offer it for download. \ However, some files may not display properly on Ubuntu's default...
...PDF reader Evince or PDF forms may not work as expected. Hence, you may still need to use it. Here is how to install the Adobe Reader (acroread) if you...