GENERATING TYPE-SAFE WRAPPERS FOR DYNAMIC DETOURING

• US 20110276943A1
• Filed: 05/05/2010
• Published: 11/10/2011
• Est. Priority Date: 05/05/2010
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Halleux, Jonathan Paul de, Tillmann, Nikolai
• Granted Patent: US 8,726,239 B2
• Time in Patent Office: Days
• US Class Current: 717/124
• CPC Class Codes: G06F 11/3696 Methods or tools to render software testable
• CPC Class Codes: G06F 8/315 Object-oriented languages
• CPC Class Codes: G06F 9/449 Object-oriented method invocation or resolution

Abstract

An isolation system is described for converting original product code into corresponding modified code. The isolation system operates by identifying a subset of original methods to be converted. For each such original method, the isolation system generates a modified part having at least one property with a type-safe delegate type which matches a signature of the original method. Test code, which tests the product code, can then associate a delegate instance to the thus-defined property of the original method. This prompts an execution system to dynamically execute detour code associated with the delegate instance, rather than an instrumentation of the original method, thus avoiding dependency on potentially non-deterministic functionality which would be otherwise invoked by an instrumentation of the original method.

Claims

1. An isolation system, implemented by electrical processing functionality, for processing product code so that the product code can be tested without dependency on external functionality, comprising:

logic configured to receive original product code, the product code containing a plurality of original methods, at least one original method being dependent on external functionality that is not under control of a test being performed;

logic configured to receive selection information which defines a subset of original methods to be processed; and

logic configured to convert each original method in the subset of original methods into a corresponding modified part, the modified part declaring a type-safe property having a delegate type.

2. The isolation system of claim 1, wherein at least one original method is a static method, and wherein said logic configured to convert is operative to declare a corresponding static-related property for each static method.

3. The isolation system of claim 1, wherein at least one original method is an instance method, and wherein said logic configured to convert is operative to declare a corresponding instance-related property and a static-related property for each instance method.

4. The isolation system of claim 1, wherein each property has a signature which matches a signature of a corresponding original method.

5. The isolation system of claim 1, wherein said logic configured to convert further comprises:

logic configured to determine whether each original method in the subset of original methods has a respective corresponding modified part that has already been generated and stored; and

logic configured to use the corresponding modified part that has already been generated and stored if the corresponding modified part exists.

6. A method for testing product code using electrical processing functionality, comprising:

receiving original product code, the product code containing an original method that is dependent on functionality that is not under control of a test being performed;

converting the original method into a type-safe modified part, the modified part declaring a property having a delegate type;

receiving test code which tests at least some aspect of the original product code, the test code assigning a delegate instance to the property; and

executing the test code using an execution system, the execution system detouring calls to an instrumentation of the original method to detour code associated with the delegate instance.

7. The method of claim 6, wherein the product code is expressed in a programming language that employs static checking and static binding.

8. The method of claim 6, wherein the product code is expressed in a .NET programming language.

9. The method of claim 6, wherein the original product code includes a collection of original methods, and wherein said converting comprises:

receiving selection information that defines a subset of original methods selected from of the collection of original methods; and

providing a subset of modified parts which are the respective corresponding versions of the subset of original methods.

10. The method of claim 9, wherein said converting further comprises:

determining whether each original method in the subset of original methods has a respective corresponding modified part that has already been generated and stored; and

using the corresponding modified part that has already been generated and stored if the corresponding modified part exists.

11. The method of claim 6, wherein the original method is defined with respect to an original class, and wherein the modified part is defined with respect to a modified class, wherein said converting comprises generating the modified class if the modified class has not been previously generated.

12. The method of claim 11, wherein said converting comprises assigning the modified class a name which is a variant of a name of the original class.

13. The method of claim 6, wherein the original method is a static method, and wherein the converting comprises declaring a corresponding static-related property.

14. The method of claim 6, wherein the original method is an instance method, and wherein the converting comprises declaring a corresponding instance-related property and a static-related property.

15. The method of claim 6, wherein the property has a signature which matches a signature of the original method.

16. The method of claim 6, wherein the property has a set operation for setting detour-related information in a detour manager module, enabling the detour manager module to identify the original method to be detoured.

17. The method of claim 6, wherein said executing comprises instrumenting the product code to interact with a detour manager.

18. The method of claim 6, wherein said executing comprises:

interacting with a detour manager module to determine if a detour has been installed for the original method;

if the detour is installed, executing the code associated with the delegate instance; and

if the detour is not installed, executing instrumented code associated with the original method.

19. A computer readable medium for storing computer readable instructions, the computer readable instructions providing an isolation system when executed by one or more processing devices, the computer readable instructions comprising:

logic configured to receive an original method that is dependent on functionality that is not under control of a test being performed; and

logic configured to convert the original method into a corresponding modified part, the modified part declaring type-safe property information that can be associated, by test code, with detour code to be executed in lieu of an instrumentation of the original method.

20. The computer readable medium of claim 19, wherein said logic configured to convert is operative to provide different kinds of property information for different respective kinds of methods.