Eclipse Labs Xtext Utils: Unit Testing helpers released

On Jul 28th we released a first version of our Xtext Unit Testing utilities. It supports makes unit-testing of Xtext-based grammars a no-brainer!!

Integration-style testing of files

A integration-style test covers many of the aspects you want to test, when writing new (test-first), or changing grammars (regression).

A simple test like this one:

@Test
public void person_no_attributes(){
    testFile("person_no_attributes.dmodel");
}

; will cover following functionality:

• Model file parsed into EMF-model with no errors
• All cross-references resolved
• Validation passed; no warnings, no errors.
• Serializer runs without errors
• Formatter runs without errors
• Serialize+Format exactly matches the input-files’ content

Further capabilities (need documentation!)

• Fluent-API for validation assertion. Example:

// error line 1: person.name-feature is missing display name
assertConstraints(
  issues.errorsOnly()
             .inLine(1)
             .under(Modul.class, "person")
             .named("name")
             .oneOfThemContains("missing display name")
);

• Switches for turning on/off serialization and formatter

Unit-testing of Parser- or Lexer-Rules

I’ll just show an example here:

@Test
public void id(){
    testTerminal("bar", /* token stream: */ "ID");
    testTerminal("bar3", /* token stream: */ "ID");
    
    testNotTerminal("3bar", /* unexpected */ "ID");
    
    // token streams with multiple token
    testTerminal("foo.bar", "ID", "'.'", "ID");
}

@Test
public void qualifiedNameWithWildcard(){
    testParserRule("foo.*", "QualifiedNameWithWildCard");
}

Download / Install

The Eclipse plugin is available on this P2 update site: http://xtext-utils.eclipselabs.org.codespot.com/git.distribution/releases/unittesting-0.9.x

The project is hosted on Google Code:

Source: http://code.google.com/a/eclipselabs.org/p/xtext-utils/source/checkout?repo=unittesting

Unit-Testing Documentation: Unit_Testing – xtext-utils – Unit testing – A collection of useful utilities and samples for Xtext based projects – Google Project Hosting