Hi,
We are having an issue with our DSL that I had to do pretty hard debugging to figure out.
In our grammar, we define Attribute(s) this way:
Attributes:
'attributes' name=ValidID
'{'
definitions+=Attribute*
'}'
;
Attribute returns xbase::XExpression:
{Attribute} (transient='transient')? type=JvmTypeReference name=ValidID ('=' defaultValue=XLiteral)?
;
We can then refers to this Attribute in an Assignment:
Assignment returns xbase::XExpression:
{Assignment}
'set' address=DotExpression ('@' attribute=[Attribute] ('.' key=ID)?)?
op=('='|':=')
expression=(XExpression|XBlockExpression)
;
The TypeComputer compute the expectations this way when an attribute is present:
// Assignment has a @attribute added. So we are referring to the PropertyAttribute
switch (type : assignment.attribute.type)
{
JvmParameterizedTypeReference case type.arguments.size == 0:
{
// Simple type
val typeRef = state.referenceOwner.toLightweightTypeReference(type)
state.withExpectation(typeRef).computeTypes(assignment.expression)
}
Our JvmModelInferrer on the other hand infers the model for Attribute(s) this way:
def dispatch infer(Attributes attributes, IJvmDeclaredTypeAcceptor acceptor, boolean isPreIndexingPhase)
{
acceptor.accept(attributes.toClass(attributes.fullyQualifiedName)) [ inferredClass |
inferredClass => [
visibility = JvmVisibility.PUBLIC
final = true
]
inferredClass.members += attributes.definitions.filter(Attribute).map [ attribute |
val genericAttributeType = typeRef("com.pc360.configurator.property.attributes.PropertyAttribute", attribute.type)
attributes.toField(attribute.name, genericAttributeType) => [
visibility = JvmVisibility.PUBLIC
static = true
final = true
initializer = attribute
]
]
]
}
Everything seemed to work fine in Eclipse but when we attempted to generate the java source files using Maven, we had a very unpleasant surprise; the inferred java type to the field generated for the attribute named "visible" was /*PropertyAttribute<Boolean>*/ Object
After pretty intense debugging, we figured out the problem: when generating the sources from Maven, the order of the processed elements is not the same as in Eclipse and in our case with Maven, before the Jvm Model
is inferred for the Attributes, the TypeComputer comes across an Assignment which happens to use the "visible" attribute. Because of that, the "type" property of the attribute is accessed, triggering the Scoping for the context which in turn trigger the Jvm Model inferring. At that point, the Attributes Model is inferred and when we process the "visible" attribute and once again ask for that attribute type, the result is "unknown" because we are in a cyclic dependency...
We were able to "fix" this problem with a super flacky hack: in the JvmModelInferrer, if the attribute name is "visible", always use java.lang.Boolean...
def dispatch infer(Attributes attributes, IJvmDeclaredTypeAcceptor acceptor, boolean isPreIndexingPhase)
{
val booleanType = typeRef("java.lang.Boolean")
acceptor.accept(attributes.toClass(attributes.fullyQualifiedName)) [ inferredClass |
inferredClass => [
visibility = JvmVisibility.PUBLIC
final = true
]
inferredClass.members += attributes.definitions.filter(Attribute).map [ attribute |
val genericAttributeType = typeRef("com.pc360.configurator.property.attributes.PropertyAttribute", if (attribute.name == "visible") booleanType else attribute.type)
attributes.toField(attribute.name, genericAttributeType) => [
visibility = JvmVisibility.PUBLIC
static = true
final = true
initializer = attribute
]
]
]
}
There must be another way to fix this...
Thank you for your help!
Dominique T.
] 
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