The current code base is not uniform. After some discussion,
we have chosen to go with double quotes by default.

Use the documented module instead of ActiveModel::Model.
This makes the example more focused.

I wrote a utility that helps find areas where you could optimize your program using a frozen string instead of a string literal, it's called [let_it_go](https://github.com/schneems/let_it_go). After going through the output and adding `.freeze` I was able to eliminate the creation of 1,114 string objects on EVERY request to [codetriage](codetriage.com). How does this impact execution?

To look at memory:

```ruby
require 'get_process_mem'

mem = GetProcessMem.new
GC.start
GC.disable
1_114.times { " " }
before = mem.mb

after = mem.mb
GC.enable
puts "Diff: #{after - before} mb"

```

Creating 1,114 string objects results in `Diff: 0.03125 mb` of RAM allocated on every request. Or 1mb every 32 requests.

To look at raw speed:

```ruby
require 'benchmark/ips'

number_of_objects_reduced = 1_114

Benchmark.ips do |x|
  x.report("freeze")    { number_of_objects_reduced.times { " ".freeze } }
  x.report("no-freeze") { number_of_objects_reduced.times { " " } }
end
```

We get the results

```
Calculating -------------------------------------
              freeze     1.428k i/100ms
           no-freeze   609.000  i/100ms
-------------------------------------------------
              freeze     14.363k (± 8.5%) i/s -     71.400k
           no-freeze      6.084k (± 8.1%) i/s -     30.450k
```

Now we can do some maths:

```ruby
ips = 6_226k # iterations / 1 second
call_time_before = 1.0 / ips # seconds per iteration 

ips = 15_254 # iterations / 1 second
call_time_after = 1.0 / ips # seconds per iteration 

diff = call_time_before - call_time_after

number_of_objects_reduced * diff * 100

# => 0.4530373333993266 miliseconds saved per request
```

So we're shaving off 1 second of execution time for every 220 requests. 

Is this going to be an insane speed boost to any Rails app: nope. Should we merge it: yep. 

p.s. If you know of a method call that doesn't modify a string input such as [String#gsub](https://github.com/schneems/let_it_go/blob/b0e2da69f0cca87ab581022baa43291cdf48638c/lib/let_it_go/core_ext/string.rb#L37) please [give me a pull request to the appropriate file](https://github.com/schneems/let_it_go/blob/b0e2da69f0cca87ab581022baa43291cdf48638c/lib/let_it_go/core_ext/string.rb#L37), or open an issue in LetItGo so we can track and freeze more strings. 

Keep those strings Frozen

![](https://www.dropbox.com/s/z4dj9fdsv213r4v/let-it-go.gif?dl=1)

Previously, calling `User.model_name.to_json` would result in an infinite
recursion as `.model_name` inherited its `.as_json` behavior from Object. This
patch fixes that unexpected behavior by delegating `.as_json` to :name.

'_singularize' only ever gets called with one argument

Also prevents the word "Model" from linking to the documentation
of ActiveModel::Model because that's not intended.

[ci skip]

The instance method `model_name` was being defined multiple times,
causing a redefinition warning.

This allows rails code to be more confdent when asking for a model name, instead of having to ask for the class.

Rails core discussion here: https://groups.google.com/forum/#!topic/rubyonrails-core/ThSaXw9y1F8

According to our guideline, we leave 1 space between `#` and `=>`, so we
want `# =>` instead of `#=>`.

Thanks to @fxn for the suggestion.

[ci skip]

- qoute example line's result when it kind of String
- right ("singular_route_key") method in example

Those two files are required by active_support/rails.rb
loaded in active_model.rb

It is common to require common dependencies on the root
files to avoid boilerplate in each file.

This reverts commit 763635e3, reversing
changes made to 4f46ef36.

There are two missing ActiveSupport dependencies to use ActiveModel::Name class or ActiveModel::Naming module independently.

Missing dependencies for Module#delegate defined in `active_support/core_ext/module/delegation`, used at [L148](https://github.com/rails/rails/blob/master/activemodel/lib/active_model/naming.rb#L148)

Missing dependencies for Object#blank? defined in `active_support/core_ext/object/blank`, used at [L131](https://github.com/rails/rails/blob/master/activemodel/lib/active_model/naming.rb#L131)

I also attempted to fix other styleguide violations such as
{ a: :b } over {a: :b} and foo(b: 'bar') over foo( b: 'bar' ).

Under a "private" call, class methods are not real private methods,
they're public just like any other method.

Make model_name_from_record_or_class a private class method, and nodoc it.

It was deprecated in 3.2