VIATRA/Query/UserDocumentation/QueryTestFramework

Query Test Framework

There is a test framework available specifically designed to test Viatra Queries. It was developed with the following use cases in mind:

• Testing the Viatra Query Engine itself
• Provide a regression testing framework for users to test patterns

Basic concepts

The framework allows the user to compare the results of a pattern execution using different engine implementation or to a predefined result set (so-called snapshot). It defines a convenient internal DSL to define test cases. A description of a test case consists of the following parts:

• What to test
  • Generated query specifications
  • Pattern groups
  • Generic pattern groups (possible parsed directly from .vql files)
• Input models
• Execution methods
  • by Rete or LocalSearch engines
  • from snapshot
• Assumption (optional)
  • Checks whether all given execution method supports the given patterns (i.e. the test case is applicable)
• Assertion
  • Checks whether the results provided by all execution methods are the same for each patterns.

Example:

ViatraQueryTest. //Entry point
test(SomeQuerySpecification::instance).and(AnotherQuerySpecification). // Patterns under test
on(modelURI). // Load instance models (this may be optional if a snapshot model references the used input model)
with(snapshot). // Compare prepared results stored by a snapshot model
with(new ReteBackendFactory). // Compare results produced by the Rete engine
assertEquals // make assertions