record_invocation
Record method invocations, query the invocations, and use predicates to verify a method's invocation
Example
class SomeClass
include RecordInvocation
def some_method(some_parameter)
record_invocation(binding)
end
record def some_recorded_method(some_parameter)
:some_result
end
end
recorder = SomeClass.new
recorder.some_method('some argument')
recorder.invoked?(:some_method)
# => true
recorder.invocation(:some_method)
# => <Invocation:0x..
@method_name=:some_method,
@parameters={:some_parameter=>"some argument"}>
# Recorded method
recorder.some_recorded_method('some other argument')
# => :some_result
recorder.invoked?(:some_recorded_method)
# => true
recorder.invocation(:some_recorded_method)
# => <Invocation:0x..
@method_name=:some_recorded_method,
@parameters={:some_parameter=>"some other argument"}>
Recording Invocations of an Object
In order to enable method invocations recording capabilities for an object, the RecordInvocation
module needs to be included in the object's class.
class SomeClass
include RecordInvocation
end
The record_invocation
Method
Invocations can be recorded by passing the current binding to the record_invocation
method.
class SomeClass
include RecordInvocation
def some_method(some_parameter, some_other_parameter)
record_invocation(binding)
end
end
recorder = SomeClass.new
recorder.some_method('some argument', 'some other argument')
recorder.invocation(:some_method)
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
The record
Macro
The record
macro allows any method to be recorded. The method's implementation doesn't have to be specialized in any way, and the method's natural behavior and return value are unchanged.
class SomeClass
include RecordInvocation
record def some_recorded_method(some_parameter)
:some_result
end
end
recorder = SomeClass.new
recorder.some_recorded_method('some other argument')
# => :some_result
recorder.invoked?(:some_recorded_method)
# => true
recorder.invocation(:some_recorded_method)
# => <Invocation:0x..
@method_name=:some_recorded_method,
@parameters={:some_parameter=>"some other argument"}>
## Querying Invocations
An invocation can be retrieved based on its method name and parameter values.
### By Method Name
``` ruby
recorder.some_method('some argument', 'some other argument')
recorder.invocation(:some_method)
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
### By Method Name and Parameter Values
recorder.invocation(:some_method, some_parameter: 'some argument')
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
recorder.invocation(:some_method, some_other_parameter: 'some other argument')
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
recorder.invocation(:some_method, some_parameter: 'some argument', some_other_parameter: 'some other argument')
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
Assuring Exactly One Invocation
If more than one invocation is found, only the first invocation will be returned using the invocation
method.
If a method should have only been invoked once, the one_invocation
method will raise an error rather than return the first invocation in cases where the method was invoked more than once.
recorder.some_method('some argument', 'some other argument')
recorder.some_method('some argument', 'yet another argument')
recorder.one_invocation(:some_method)
# => More than one invocation record matches (Method Name: :some_method, Parameters: {}) (RecordInvocation::Error)
recorder.one_invocation(:some_method, some_parameter: 'some argument')
# => More than one invocation record matches (Method Name: :some_method, Parameters: {:some_parameter=>"some argument"}) (RecordInvocation::Error)
If only one invocation of the method was recorded, then that invocation will be returned, just as it does with the invocation
method.
recorder.some_method('some argument', 'some other argument')
recorder.one_invocation(:some_method, some_parameter: 'some argument')
# => #<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>
Retrieving More than One Invocation
If a method is invoked more than once, multiple invocation records can be retrieved.
recorder.some_method('some argument', 'some other argument')
recorder.some_method('another argument', 'yet another argument')
recorder.invocations(:some_method)
# => [#<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>,
#<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"another argument", :some_other_parameter=>"yet another argument"}>]
recorder.invocations(:some_random_method)
# => []
recorder.invocations(:some_method, some_parameter: 'some argument')
# => [#<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>]
recorder.invocations(:some_method, some_other_parameter: 'some other argument')
# => [#<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>]
recorder.invocations(:some_method, some_parameter: 'some argument', some_other_parameter: 'some other argument')
# => [#<Invocation:0x...
@method_name=:some_method,
@parameters={:some_parameter=>"some argument", :some_other_parameter=>"some other argument"}>]
Detecting Invocations
RecordInvocation
provides predicates for detecting whether an invocation has been made.
recorder.some_method('some argument', 'some other argument')
recorder.invoked?(:some_method)
# => true
recorder.invoked?(:some_random_method)
# => false
recorder.invoked?(:some_method, some_parameter: 'some argument')
# => true
recorder.invoked?(:some_method, some_other_parameter: 'some other argument')
# => true
recorder.invoked?(:some_method, some_parameter: 'some argument', some_other_parameter: 'some other argument')
# => true
Detecting Exactly One Invocation
If a method should have only been invoked once, the invoked_once?
predicate will raise an error if more than one matching invocation is detected.
recorder.some_method('some argument', 'some other argument')
recorder.some_method('some argument', 'yet another argument')
recorder.invoked_once?(:some_method)
# => More than one invocation record matches (Method Name: :some_method, Parameters: {}) (RecordInvocation::Error)
recorder.invoked_once?(:some_method, some_parameter: 'some argument')
# => More than one invocation record matches (Method Name: :some_method, Parameters: {:some_parameter=>"some argument"}) (RecordInvocation::Error)
If only one invocation of the method was recorded, then the invoked?
predicate will respond affirmatively.
recorder.some_method('some argument', 'some other argument')
recorder.invoked_once?(:some_method, some_parameter: 'some argument')
# => true
The methods of the recorder may conflict with the methods implemented on the RecordInvocation
module. If so, a secondary set of method names may be used to access the diagnostic functions provided by RecordInvocation
:
- __invocation
- __invocations
- __invoked?
- __invoked_once?
- __record_invocation