摘要:
A system for testing programs using a digital processor and programs in computer memory. A mock behavior generator identifies an interface indicated for mock behavior. The interface is identified as an input parameter of a parameterized unit test. The mock behavior generator creates a symbolic object with stubs to receive calls and mock behavior that returns symbolic values upon receiving a call to the stub. A symbolic executor, symbolically executes the parameterized unit test to obtain path constraints for an implementation under test, and at least one path constraint includes the symbol returned in response to the call to the stub. A constraint solver provides solutions for the paths including concrete values assigned to returned symbols. The mock behavior generator creates mock objects that return the concrete values when the implementation under test is executed.
摘要:
A finite domain approximation for symbolic terms of a symbolic state is derived, given some finite domains for basic terms of the symbolic state. A method is executed recursively for symbolic sub-terms of a symbolic term, providing a domain over-approximation that can then be provided to a solver for determining a more accurate domain. The method can be applied to a wide array of system terms, including, for example, object states, arrays, and runtime types.
摘要:
Separation of parameterized unit tests from specific test cases supports many benefits including automated test case generation. Symbolic execution assigns symbolic input variables to parameters of a parameterized unit test. Path constraints of an implementation under test (IUT) are identified during symbolic execution. A constraint solver automatically generates test cases by determining the test inputs that satisfy one of more paths, each described by constraints, through the IUT. Parameterized unit tests are used to populate behavioral summaries. Behavioral summaries are used later in future symbolic executions to emulate summarized methods. An intensional heap is provided to represent state changes performed by summarized methods. The extensional heap is used to explicitly update memory locations, e.g. object fields or array elements.
摘要:
Techniques and tools for testing multi-threaded or distributed software systems are described. For example, a multi-threaded system is instrumented and executed to produce logs of events that are performed by each of its agents. The agent logs contain a totally ordered series of events per agent, as well as information about accesses to resources shared between the agents. With this information, a partial ordering of the events performed by all the agents is described for the execution. The agent logs are then multiplexed into one or more serialized event orderings, which can then be compared to a specification of the system in a conformance testing engine.
摘要:
A computerized method receives an implementation comprising a modifier method and an observer method of a class implementing an abstract data type. The method symbolically executes the modifier method to obtain constrained states, and applies the observer method in constrained states to obtain specialized axioms. The method then creates a specification from the obtained specialized axioms based on generalizing, merging and simplifying the specialized axioms.
摘要:
The present invention relates to a system and methodology to enable programming of generalized comprehensions in an imperative language environment. In one aspect, a system is provided to facilitate employment of user-definable and generalized comprehensions in accordance with imperative languages. The system includes a language component to enable programming of comprehension notations in an imperative language and an interface component to describe a meaning of the comprehension notations. A translation component facilitates execution of the comprehension notations in accordance with the imperative language.
摘要:
Described herein are methods and systems for interactively configuring and producing a data domain for various data structure elements of a computer program. A domain configuration manager is described which interactively receives domain configuration information corresponding to a data structure element, reads a reflection of the program and produces a data domain according to domain configuration information. The domain configuration manager is capable of producing a data domain for a data structure element according to such domain configuration information such as an explicit expression, inheritance or domain generation technique. The reflection of the computer program exposes the methods and functions of the program to be used in the explicit expression regardless of the visibility rules. Also, predicates and conditions can be used with domain generation techniques to further narrowly configure the data domains.
摘要:
A test domain configuration module generates graphical user interfaces for identifying information about desired tests such as data types and domain configurations, and collects information used by other modules to generate tests. The identified information may include, for example, an abstract syntax, a static semantic, max counts on instances of data types, or costs of field accesses or data types for max path costs or max expression costs. A test input generator, generates test input for the identified and configured data types. In one case, the generated test inputs are generated as tree data structures. A predicate determines whether a generated test input follows semantic conditions. A test input evaluator counts instances of data types in, sums paths through, or sums total costs of, the generated test inputs. A test acceptance module saves test inputs acceptable to the predicate and the test input evaluator.
摘要:
The technology contributes the inference of formal specifications automatically, which can increase the acceptance of specifications. The technology introduces the symbolic execution of a modifier method to explore its behavior and then summarizing the results of the exploration using observer methods. This often results in concise, understandable specifications, which are a prerequisite for human analysis. Optionally, a generated specification is deemed sound and or complete. The specifications are presented as traditional pre-/post-condition specifications or parameterized unit tests. The former often serve as inputs to a program verification system, whereas the latter often provide inputs for tools that generate test cases.
摘要:
Symbolic execution identifies possible execution paths of a computer program or method, each having certain constraints over the input values. The symbolic execution also records updates of memory locations, e.g. updates of the fields of symbolic objects in the heap of an object oriented program, involving a description of the previous heap, the updated symbolic object, a field identification, and a newly assigned symbolic value. The symbolic execution can also record calls to summarized methods, involving a description of previous calls, an identification of the summarized methods, and its symbolic arguments. The behavior of summarized methods can be expressed by axioms. Axioms describe the relationship between summarized methods under certain conditions. Axioms can be generated from parameterized unit tests. A parameterized unit test is a method with parameters which executes a sequence of calls to methods of an implementation under test; it asserts constraints over the inputs and outputs of the calls. A software testing program receives a parameterized unit test of an implementation under test, and symbolically executes the parameterized unit test. It can re-use axioms generated from other parameterized unit tests, and use them to emulate summarized methods.