Inspired by @tenderlove's work in
c363fff29f, this reduces the number of
strings allocated when running callbacks for ActiveRecord instances. I
measured that using this script:
```
require 'objspace'
require 'active_record'
require 'allocation_tracer'
ActiveRecord::Base.establish_connection adapter: "sqlite3",
database: ":memory:"
ActiveRecord::Base.connection.instance_eval do
create_table(:articles) { |t| t.string :name }
end
class Article < ActiveRecord::Base; end
a = Article.create name: "foo"
a = Article.find a.id
N = 10
result = ObjectSpace::AllocationTracer.trace do
N.times { Article.find a.id }
end
result.sort.each do |k,v|
p k => v
end
puts "total: #{result.values.map(&:first).inject(:+)}"
```
When I run this against master and this branch I get this output:
```
pete@balloon:~/projects/rails/activerecord$ git checkout master
M Gemfile
Switched to branch 'master'
pete@balloon:~/projects/rails/activerecord$ bundle exec ruby benchmark_allocation_with_callback_send.rb > allocations_before
pete@balloon:~/projects/rails/activerecord$ git checkout remove-dynamic-send-on-built-in-callbacks
M Gemfile
Switched to branch 'remove-dynamic-send-on-built-in-callbacks'
pete@balloon:~/projects/rails/activerecord$ bundle exec ruby benchmark_allocation_with_callback_send.rb > allocations_after
pete@balloon:~/projects/rails/activerecord$ diff allocations_before allocations_after
39d38
<
{["/home/pete/projects/rails/activesupport/lib/active_support/callbacks.rb",
81]=>[40, 0, 0, 0, 0, 0]}
42c41
< total: 630
---
> total: 590
```
In addition to this, there are two micro-optimizations present:
* Using `block.call if block` vs `yield if block_given?` when the block was being captured already.
```
pete@balloon:~/projects$ cat benchmark_block_call_vs_yield.rb
require 'benchmark/ips'
def block_capture_with_yield &block
yield if block_given?
end
def block_capture_with_call &block
block.call if block
end
def no_block_capture
yield if block_given?
end
Benchmark.ips do |b|
b.report("block_capture_with_yield") { block_capture_with_yield }
b.report("block_capture_with_call") { block_capture_with_call }
b.report("no_block_capture") { no_block_capture }
end
pete@balloon:~/projects$ ruby benchmark_block_call_vs_yield.rb
Calculating -------------------------------------
block_capture_with_yield
124979 i/100ms
block_capture_with_call
138340 i/100ms
no_block_capture 136827 i/100ms
-------------------------------------------------
block_capture_with_yield
5703108.9 (±2.4%) i/s - 28495212 in 4.999368s
block_capture_with_call
6840730.5 (±3.6%) i/s - 34169980 in 5.002649s
no_block_capture 5821141.4 (±2.8%) i/s - 29144151 in 5.010580s
```
* Defining and calling methods instead of using send.
```
pete@balloon:~/projects$ cat benchmark_method_call_vs_send.rb
require 'benchmark/ips'
class Foo
def tacos
nil
end
end
my_foo = Foo.new
Benchmark.ips do |b|
b.report('send') { my_foo.send('tacos') }
b.report('call') { my_foo.tacos }
end
pete@balloon:~/projects$ ruby benchmark_method_call_vs_send.rb
Calculating -------------------------------------
send 97736 i/100ms
call 151142 i/100ms
-------------------------------------------------
send 2683730.3 (±2.8%) i/s - 13487568 in 5.029763s
call 8005963.9 (±2.7%) i/s - 40052630 in 5.006604s
```
The result of this is making typical ActiveRecord operations slightly faster:
https://gist.github.com/phiggins/e46e51dcc7edb45b5f98
Since we want this flag to be enabled anytime we are running the tests
under JRuby, let's enable this at the Rakefile level so people get the
performance boost on their local checkout.
Moreover, we avoid having to update this particular line anytime the
option changes on the JRuby side.
The only drawback is that we have to define it in every Rakefile but
there's no big deal, this is already the case for other options.
Goals:
1. Default to :random for newly generated applications
2. Default to :sorted for existing applications with a warning
3. Only show the warning once
4. Only show the warning if the app actually uses AS::TestCase
Fixes#16769
When we are loading a component and we want to know its version, we are
actually not speaking about the constant but the library itself.
[ci skip]
[Godfrey Chan & Xavier Noria]
The functionality has not changed, but the code is more elegant by
using `reduce` instead of `each`.
This way no accumulator needs to be declared, no explicit return is
needed.
If the request parameters are passed to create_with and where they can
be used to do mass assignment when used in combination with
Relation#create.
Fixes CVE-2014-3514
Conflicts:
activerecord/lib/active_record/relation/query_methods.rb
Calling ActiveSupport::TestCase.i_suck_and_my_tests_are_order_dependent! in AS::TestCase makes
everyone's tests order dependent, which should never be done by the framework.
We are planning to remove mocha from our test suite because of
performance problems. To make this possible we should stop require mocha
on ActionSupport::TestCase.
This should not affect applications since users still need to add mocha
to Gemfile and this already load mocha.
Added FIXME notes to place that still need mocha removal
This change prevents a certain class of user error which results when
mistakenly using the `validate` class method instead of the `validates`
class method.
Only apply when all arguments are symbols, because some validations use
the `validate` method and pass in additional options, namely the
`LenghValidator` via the `ActiveMode::Validations::validates_with`
method.
These methods may cause confusion with the `reset_changes` that
behaves differently
of them.
Also rename undo_changes to restore_changes to match this new set of
methods.
This method name is causing confusion with the `reset_#{attribute}`
methods. While `reset_name` set the value of the name attribute for the
previous value the `reset_changes` only discard the changes and previous
changes.
Michael Genereux