Implementing the choice type

Related to this pull request.

Implementation

In the PanParser.jjt file, another OR option was added to baseTypeSpec():

t=<CHOICE> <LPAREN> stringLiteral() (<COMMA> stringLiteral())` e=<RPAREN>

This will specifically match the Choice-type.

ChoiceType extends AdvancedType, a very simple super class used to define more advanced types. The AdvancedType class inherits from the BaseType class. This is required because all types are wrapped in a FullType and a FullType contains a BaseType. Since the actual identifier is choice, and not a primitive type, we use the identifier to make the difference between a normal AliasType and a ChoiceType in PanParserAstUtils.astToType(). The validation phase checks if the value of an element is one of the possible choices.

This type requires that the input arguments are strings, thus no variables referencing strings, since the arguments of a type can’t be executed during the build phase.

Tests

• Added a ChoiceTypeTest to test/java/org/quattor/pan/type/.
• Added pan test files to test/pan/Functionality/types/choice.