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Search syntax

  • Search for repeating cards with repeats:yes
  • Search for unfinished cards with unfinished:yes
  • Search for cards in a certain topic with topic:"name"
  • Search for phrases with "a phrase"
  • Exclude a word from search: -word
  • Exclude a phrase from search: -"a phrase"
  • Exclude a topic from search: -topic:"name"
External content

nruth/show_me_the_cookies - GitHub

Some helpers for poking around at your Capybara driven browser's cookies in integration tests.

Supports Capybara's bundled drivers (rack-test, Selenium Webdriver), and adapters for other drivers may be added.

Mysql::Error: SAVEPOINT active_record_1 does not exist: ROLLBACK TO SAVEPOINT active_record_1 (ActiveRecord::StatementInvalid)

Possible Reason 1: parallel_tests - running more processes than features

If you run old versions of parallel_tests with more processes than you have Cucumber features, you will get errors like this in unexpected places:

This is a bug caused by multiple processes running the same features on the same database.

The bug is fixed in versions 0.6.18+.


Test whether a form field exists with Cucumber and Capybara

The step definition below lets you say:

 Then I should see a field "Password"
 But I should not see a field "Role"

Here is the step definition:

Then /^I should( not)? see a field "([^"]*)"$/ do |negate, name|
  expectation = negate ? :should_not : :should
    field = find_field(name)
  rescue Capybara::ElementNotFound
    # In Capybara 0.4+ #find_field raises an error instead of returning nil
  field.send(expectation, be_present)

Note that you might have to adapt the step defi…

Sunspot for Solr fails with '400 Bad Request' in 'adapt_response'

If Sunspot does not work and fails with a backtrace similar to this:

/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:227:in `adapt_response'
/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:164:in `execute'
/project/shared/bundle/ruby/1.8/gems/rsolr-1.0.6/lib/rsolr/client.rb:158:in `send_and_receive'
(eval):2:in `post'

then the schema.xml that is shipped with Sunspot is not loaded into Solr correctly.

Often the latter can be found in /etc/solr/conf/schema.xml. So copy Sunspo…

Associations named using a string cannot be included in a scope

If you defined your association via

class Article
  belongs_to "category"

and you try

Article.scoped(:include => :category)

you will get an error message

in `preload_one_association': Association named 'category' was not found; perhaps you misspelled it? (ActiveRecord::ConfigurationError)


Always define your assocations via symbol

class Article
  belongs_to :category

Flexible overflow handling with CSS and JavaScript

You can use text-overflow to truncate a text using CSS but it does not fit fancy requirements.

Here is a hack for the special case where you want to truncate one of two strings in one line that can both vary in length, while fully keeping one of them. See this example screenshot where we never want to show an ellipsis for the distance:

![Flexible overflow with optional ellipsis](…

Using Vim to repair files with incorrect character encoding/representation

Consider you have a file that uses improper encoding on special characters. Example: You see the latin1 version "ñ" for the UTF-8 "ñ" but the file itself is stored as UTF-8 (meaning that the UTF-8 bytes are doubly encoded).

You can fix that easily with Vim:

vim broken.file

Now you tell vim that the file's encoding is actually latin1 (you can see what Vim is currently using by saying only :set fileencoding):

:set fileencoding=latin1

Write and reload the file:


All should be good now.

Adjust to your n…

Ubuntu: Reload Gnome panel while keeping user session

Sometimes you need to restart the Gnome panel, e.g. when you installed a new Gnome panel widget but the widget list was cached before.

You often don't want to do sign out and back in for this.
Instead, just run:

killall gnome-panel

This will terminate all gnome-panel processes. On my machine (Ubuntu 11.04) the panel then restarted itself after a moment.

If the panel does not automatically come back, press Alt+F2 to bring up the Gnome "run" box and start gnome-panel from there.

Why your javascripts should be executed after the dom has been loaded

Most of the JavaScript snippets have code that manipulates the DOM. For that reason dom manipulating javascript code should have been executed after the DOM has loaded completely. That means when the browser has finished HTML parsing and built the DOM tree. At that time, you can manipualte the DOM although not all resources (like images) are fully loaded.

The following snippets show how you can do this with plain JavaScript, jquery or prototype ([dom ready …

How to combine greps on log files opened with tail -f

In order to chain greps on log files that are opened via tail -f test.log you have to use the --line-buffered command line option for grep.

Imagine you have the following content in your log file.

# content for log/test.log
test foo
test foo bar baz

Now if you would like to grep for lines that contain foo but not bar, you can use the following command chain:

$ tail -f log/test.log | grep --line-buffered "foo" | grep -v "bar"

test foo    

How to create Excel sheets with spreadsheet gem and use number formats for cells like money or date

The following snippet demonstrates how you could create excel files (with spreadsheet gem) and format columns so that they follow a specific number format like currencies or dates do.

require 'rubygems'
require 'spreadsheet'

Spreadsheet.client_encoding = 'UTF-8'

book =
sheet1 = book.create_worksheet :name => 'test'

money_format = :number_format => "#,##0.00 [$€-407]"
date_format = :num...

Use CSS "text-overflow" to truncate long texts

When using Rails to truncate strings, you may end up with strings that are still too long for their container or are not as long as they could be. You can get a prettier result using stylesheets.

The CSS property text-overflow: ellipsis has been around for quite a long time now but since Firefox did not support it for ages, you did not use it. Since Firefox 7 you can!

Consider this HTML and Sass for a box that is not wide enough for its content:

<div id="greetings">
  Hello universe!
External content

Desktop Notifications with WebKit

Chrome now supports desktop notifications using WebKit's webkitNotifications API. This means you can create popup bubbles from Javascript.

External content

paul/progress_bar - GitHub

ProgressBar is a simple Ruby library for displaying progress of long-running tasks on the console. It is intended to be as simple to use as possible.

Git: Move a commit between repositories

If you want to move a complete commit from one repository to another (and you don't want to add it as a remote), you can use these steps:

Create a patch

In the source repository, create a patch based on the commit by running
git format-patch SHA1_OF_COMMIT~..SHA1_OF_COMMIT
(note the ~).
This will create a .patch file that describes this commit.

Apply the patch

In the target repository, apply the patch with
git apply PATH_TO_PATCH

If the patch does not apply cleanly, git will not do anything. I…

Git: Diff staged changes

Saying git diff only shows unstaged changes against HEAD (or any hash or branch you supplied) but leaves out files you already staged for the next commit.

To diff your added changes, say:

git diff --cached

Effectively, this gives you the changes you will commit when you run git commit without the -a switch.

Using Solr with Sunspot

This describes all the steps you'll need to get Solr up and running for your project using the Sunspot gem.

Prepare Sunspot on your development machine

What you want in your Gemfile:

gem 'sunspot_rails'
gem 'sunspot_solr'
gem 'progress_bar' # for sunspot:solr:reindex

Now define what should be indexed within Solr from your ActiveRecord models, e.g.,

class Article << ActiveRecord::Base

  searchable do
    text :title
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