diff options
Diffstat (limited to 'guides/source')
| -rw-r--r-- | guides/source/active_support_core_extensions.md | 87 | ||||
| -rw-r--r-- | guides/source/active_support_instrumentation.md | 14 | ||||
| -rw-r--r-- | guides/source/configuring.md | 2 | ||||
| -rw-r--r-- | guides/source/getting_started.md | 2 | ||||
| -rw-r--r-- | guides/source/testing.md | 8 | ||||
| -rw-r--r-- | guides/source/upgrading_ruby_on_rails.md | 2 |
6 files changed, 21 insertions, 94 deletions
diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md index 6b0554bb5f..3db46bc42e 100644 --- a/guides/source/active_support_core_extensions.md +++ b/guides/source/active_support_core_extensions.md @@ -2132,30 +2132,6 @@ The methods `second`, `third`, `fourth`, and `fifth` return the corresponding el NOTE: Defined in `active_support/core_ext/array/access.rb`. -### Adding Elements - -#### `prepend` - -This method is an alias of `Array#unshift`. - -```ruby -%w(a b c d).prepend('e') # => ["e", "a", "b", "c", "d"] -[].prepend(10) # => [10] -``` - -NOTE: Defined in `active_support/core_ext/array/prepend_and_append.rb`. - -#### `append` - -This method is an alias of `Array#<<`. - -```ruby -%w(a b c d).append('e') # => ["a", "b", "c", "d", "e"] -[].append([1,2]) # => [[1, 2]] -``` - -NOTE: Defined in `active_support/core_ext/array/prepend_and_append.rb`. - ### Extracting The method `extract!` removes and returns the elements for which the block returns a true value. @@ -2646,48 +2622,6 @@ There's also the bang variant `except!` that removes keys in the very receiver. NOTE: Defined in `active_support/core_ext/hash/except.rb`. -#### `transform_keys` and `transform_keys!` - -The method `transform_keys` accepts a block and returns a hash that has applied the block operations to each of the keys in the receiver: - -```ruby -{nil => nil, 1 => 1, a: :a}.transform_keys { |key| key.to_s.upcase } -# => {"" => nil, "1" => 1, "A" => :a} -``` - -In case of key collision, one of the values will be chosen. The chosen value may not always be the same given the same hash: - -```ruby -{"a" => 1, a: 2}.transform_keys { |key| key.to_s.upcase } -# The result could either be -# => {"A"=>2} -# or -# => {"A"=>1} -``` - -This method may be useful for example to build specialized conversions. For instance `stringify_keys` and `symbolize_keys` use `transform_keys` to perform their key conversions: - -```ruby -def stringify_keys - transform_keys { |key| key.to_s } -end -... -def symbolize_keys - transform_keys { |key| key.to_sym rescue key } -end -``` - -There's also the bang variant `transform_keys!` that applies the block operations to keys in the very receiver. - -Besides that, one can use `deep_transform_keys` and `deep_transform_keys!` to perform the block operation on all the keys in the given hash and all the hashes nested into it. An example of the result is: - -```ruby -{nil => nil, 1 => 1, nested: {a: 3, 5 => 5}}.deep_transform_keys { |key| key.to_s.upcase } -# => {""=>nil, "1"=>1, "NESTED"=>{"A"=>3, "5"=>5}} -``` - -NOTE: Defined in `active_support/core_ext/hash/keys.rb`. - #### `stringify_keys` and `stringify_keys!` The method `stringify_keys` returns a hash that has a stringified version of the keys in the receiver. It does so by sending `to_s` to them: @@ -2795,26 +2729,7 @@ NOTE: Defined in `active_support/core_ext/hash/keys.rb`. ### Slicing -Ruby has built-in support for taking slices out of strings and arrays. Active Support extends slicing to hashes: - -```ruby -{a: 1, b: 2, c: 3}.slice(:a, :c) -# => {:a=>1, :c=>3} - -{a: 1, b: 2, c: 3}.slice(:b, :X) -# => {:b=>2} # non-existing keys are ignored -``` - -If the receiver responds to `convert_key` keys are normalized: - -```ruby -{a: 1, b: 2}.with_indifferent_access.slice("a") -# => {:a=>1} -``` - -NOTE. Slicing may come in handy for sanitizing option hashes with a white list of keys. - -There's also `slice!` which in addition to perform a slice in place returns what's removed: +The method `slice!` replaces the hash with only the given keys and returns a hash containing the removed key/value pairs. ```ruby hash = {a: 1, b: 2} diff --git a/guides/source/active_support_instrumentation.md b/guides/source/active_support_instrumentation.md index 64db141381..5e68b3f400 100644 --- a/guides/source/active_support_instrumentation.md +++ b/guides/source/active_support_instrumentation.md @@ -648,6 +648,18 @@ ActiveSupport::Notifications.subscribe "process_action.action_controller" do |*a end ``` +You may also pass block with only one argument, it will yield an event object to the block: + +```ruby +ActiveSupport::Notifications.subscribe "process_action.action_controller" do |event| + event.name # => "process_action.action_controller" + event.duration # => 10 (in milliseconds) + event.payload # => {:extra=>information} + + Rails.logger.info "#{event} Received!" +end +``` + Most times you only care about the data itself. Here is a shortcut to just get the data. ```ruby @@ -672,7 +684,7 @@ Creating custom events Adding your own events is easy as well. `ActiveSupport::Notifications` will take care of all the heavy lifting for you. Simply call `instrument` with a `name`, `payload` and a block. The notification will be sent after the block returns. `ActiveSupport` will generate the start and end times -and add the instrumenter's unique ID. All data passed into the `instrument` call will make +and add the instrumenter's unique ID. All data passed into the `instrument` call will make it into the payload. Here's an example: diff --git a/guides/source/configuring.md b/guides/source/configuring.md index 029ae1a5ff..ae1de3079f 100644 --- a/guides/source/configuring.md +++ b/guides/source/configuring.md @@ -1404,7 +1404,7 @@ Custom configuration You can configure your own code through the Rails configuration object with custom configuration under either the `config.x` namespace, or `config` directly. The key difference between these two is that you should be using `config.x` if you -are defining _nested_ configuration (ex: `config.x.nested.nested.hi`), and just +are defining _nested_ configuration (ex: `config.x.nested.hi`), and just `config` for _single level_ configuration (ex: `config.hello`). ```ruby diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md index e2f558d74c..264c94326e 100644 --- a/guides/source/getting_started.md +++ b/guides/source/getting_started.md @@ -90,7 +90,7 @@ $ ruby -v ruby 2.5.0 ``` -Rails requires Ruby version 2.4.1 or later. If the version number returned is +Rails requires Ruby version 2.5.0 or later. If the version number returned is less than that number, you'll need to install a fresh copy of Ruby. TIP: To quickly install Ruby and Ruby on Rails on your system in Windows, you can use diff --git a/guides/source/testing.md b/guides/source/testing.md index 9541598b26..f34f9d95f4 100644 --- a/guides/source/testing.md +++ b/guides/source/testing.md @@ -473,8 +473,8 @@ takes your entire test suite to run. ### Parallel testing with processes The default parallelization method is to fork processes using Ruby's DRb system. The processes -are forked based on the number of workers provided. The default is 2, but can be changed by the -number passed to the parallelize method. +are forked based on the number of workers provided. The default number is the actual core count +on the machine you are on, but can be changed by the number passed to the parallelize method. To enable parallelization add the following to your `test_helper.rb`: @@ -516,7 +516,7 @@ class ActiveSupport::TestCase # cleanup databases end - parallelize(workers: 2) + parallelize(workers: :number_of_processors) end ``` @@ -531,7 +531,7 @@ To change the parallelization method to use threads over forks put the following ```ruby class ActiveSupport::TestCase - parallelize(workers: 2, with: :threads) + parallelize(workers: :number_of_processors, with: :threads) end ``` diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md index e74985c5b0..2682c6ffd7 100644 --- a/guides/source/upgrading_ruby_on_rails.md +++ b/guides/source/upgrading_ruby_on_rails.md @@ -35,7 +35,7 @@ You can find a list of all released Rails versions [here](https://rubygems.org/g Rails generally stays close to the latest released Ruby version when it's released: -* Rails 6 requires Ruby 2.4.1 or newer. +* Rails 6 requires Ruby 2.5.0 or newer. * Rails 5 requires Ruby 2.2.2 or newer. * Rails 4 prefers Ruby 2.0 and requires 1.9.3 or newer. * Rails 3.2.x is the last branch to support Ruby 1.8.7. |