Generally, RSpec specs describe the expected behavior of code. While RSpec is fairly young, there are some conventions for writing specs. The RubySpecs cover a wide variety of components, so we have developed some pragmatic conventions to handle the various situations. As noted below, some conventions are more rigid than others.
These conventions apply to all specs. Existing specs that deviate from these conventions need to be fixed. Consistency is the principle that will almost always trump other conventions. Consistency aids understanding and readability. There are many thousands of lines of code in the spec files, so the value of consistency cannot be overstated.