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:
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:
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.
摘要:
A computer system provides a test program and one or more unit tests, such as a traditional unit test and or a parameterized unit test. The system also includes a constraint solver, a theorem prover, an implementation under test, a symbolic executor, a generalizor, and generated test cases. The generalizor receives a traditional unit tests as input, and modifies the traditional unit test into a parameterized unit test. The modification includes replacing plural concrete values in the traditional unit test with symbols, and exporting the symbols into a signature of the parameterized unit test. A symbolic executor identifies constraints while symbolically executing the created parameterized unit test of the implementation under test. A constraint solver and or theorem prover generates a set of test cases by solving for values that satisfy the series of constraints. The test program executes the automatically generated test cases.
摘要:
Techniques and tools for generating finite state machines (“FSMs”) for a software system with asynchronous callbacks are described. For example, method invocations in a model of the software system are partitioned into observable and controlled method invocations. The controlled method invocations are those which can be run from a test harness while the observed method invocations are those which are observed asynchronously as they are invoked in the system. An FSM is created with observation and control nodes such that observable transitions are found from observation nodes and controlled transitions are found from control nodes. If a state of the model contains both controlled and observable invocations, a timeout transition is added to the FSM to give an implementation time to come up with an observed method invocation before continuing to controlled invocations.
摘要:
State spaces are traversed to produce test cases, or test coverage. Test coverage is a test suite of sequences. Accepting states are defined. Expected costs are assigned to the test graph states. Strategies are created providing transitions to states with lower expected costs. Linear programs and other approximations are discussed for providing expected costs. Strategies are more likely to provide access to an accepting state, based on expected costs. Strategies are used to append transitions to test segments such that the new test segment ends in an accepting state.
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 method and apparatus to generate a test suite from an abstract state machine (ASM) involves generating a finite state machine (FSM) for the ASM, and generating the test suite from the FSM. An initial state of the ASM is selected. A first encoding having a plurality of bits is generated to represent the initial state. Each bit of the first encoding represents a result of an evaluation of a non-trivial guard condition of the ASM. The initial state is associated with the first encoding in the data structure for the FSM. At least one other states of the ASM are identified that result from applying at least one actions of the ASM to the initial state. At least one other encodings are generated, each of the at least one other encodings corresponding to one of the at least one other states, and for each one of the at least one other states, when the corresponding of the at least one other encodings is not the same as the any one encoding already associated with a state in the data structure, data is included in the data structure associating the one of the at least one other states and a corresponding of the at least one other encodings.
摘要:
Separation of parameterized unit tests (PUTs) 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. PUTs are used to populate behavioral summaries. Behavioral summaries are used later in future symbolic executions to emulate summarized methods. Behavioral summaries comprise behavioral purity axioms. Behavioral purity axioms require that an intensional heap before execution of a PUT be equal to the intensional heap after execution. 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 generating test cases for methods or programs with input preconditions are described. For example, after finding feasible control flow paths for a tested method along with each path's associated input conditions, a new program is created which tests these conditions along with the precondition. By analyzing this new program's control flow graph, a class of test cases is found while avoiding inefficiencies created by doing complete searches of paths through the combined control flow graph of the precondition and the method. Additional efficiencies are introduced by partitioning a control flow graph for the precondition into branched and straight sections.