rspec/rspec-expectations — pull request #259 by tinogomes (2013-05-31 15:06:40+00:00)
Title: Custom failure message for satisfy

"expected value to safisty block" is not always the best message ;)

```ruby
describe Stuff do
it "fails with custom failure message if block returns false" do
expect {
expect(false).to satisfy("should be false") { |val| val }
}.to fail_with("should be false")

expect do
expect(false).to satisfy("should be false") do |val|
val
end
end.to fail_with("should be false")
end
end
```