npropdef.build_signature(self)
end
for npropdef in nclassdef2.n_propdefs do
+ if not npropdef isa ATypePropdef then continue
+ # Check circularity
+ var mpropdef = npropdef.mpropdef
+ if mpropdef == null then continue
+ if mpropdef.bound == null then continue
+ if not check_virtual_types_circularity(npropdef, mpropdef.mproperty, mclassdef.bound_mtype, mclassdef.mmodule) then
+ # Invalidate the bound
+ mpropdef.bound = mclassdef.mmodule.model.null_type
+ end
+ end
+ for npropdef in nclassdef2.n_propdefs do
# Check ATypePropdef first since they may be required for the other properties
if not npropdef isa ATypePropdef then continue
npropdef.check_signature(self)
mmodule_type = mtype.mproperty.intro_mclassdef.mmodule
else if mtype isa MParameterType then
# nothing, always visible
+ else if mtype isa MNullType then
+ # nothing to do.
else
node.debug "Unexpected type {mtype}"
abort
for t in mtype.arguments do check_visibility(node, t, mpropdef)
end
end
+
+ # Detect circularity errors for virtual types.
+ fun check_virtual_types_circularity(node: ANode, mproperty: MVirtualTypeProp, recv: MType, mmodule: MModule): Bool
+ do
+ # Check circularity
+ # Slow case: progress on each resolution until we visit all without getting a loop
+
+ # The graph used to detect loops
+ var mtype = mproperty.mvirtualtype
+ var poset = new POSet[MType]
+
+ # The work-list of type to resolve
+ var todo = new List[MType]
+ todo.add mtype
+
+ while not todo.is_empty do
+ # The visited type
+ var t = todo.pop
+
+ if not t.need_anchor then continue
+
+ # Get the types derived of `t` (subtypes and bounds)
+ var nexts
+ if t isa MNullableType then
+ nexts = [t.mtype]
+ else if t isa MGenericType then
+ nexts = t.arguments
+ else if t isa MVirtualType then
+ var vt = t.mproperty
+ # Because `vt` is possibly unchecked, we have to do the bound-lookup manually
+ var defs = vt.lookup_definitions(mmodule, recv)
+ # TODO something to manage correctly bound conflicts
+ assert not defs.is_empty
+ nexts = new Array[MType]
+ for d in defs do
+ var next = defs.first.bound
+ if next == null then return false
+ nexts.add next
+ end
+ else if t isa MClassType then
+ # Basic type, nothing to to
+ continue
+ else if t isa MParameterType then
+ # Parameter types cannot depend on virtual types, so nothing to do
+ continue
+ else
+ abort
+ end
+
+ # For each one
+ for next in nexts do
+ if poset.has_edge(next, t) then
+ if mtype == next then
+ error(node, "Error: circularity of virtual type definition: {next} <-> {t}")
+ else
+ error(node, "Error: circularity of virtual type definition: {mtype} -> {next} <-> {t}")
+ end
+ return false
+ else
+ poset.add_edge(t, next)
+ todo.add next
+ end
+ end
+ end
+ return true
+ end
end
redef class MPropDef
var mpropdef = self.mpropdef
if mpropdef == null then return # Error thus skipped
- var bound = self.mpropdef.bound
+ var bound = mpropdef.bound
if bound == null then return # Error thus skipped
modelbuilder.check_visibility(n_type, bound, mpropdef)
var mmodule = mclassdef.mmodule
var anchor = mclassdef.bound_mtype
- # Check circularity
- if bound isa MVirtualType then
- # Slow case: progress on each resolution until: (i) we loop, or (ii) we found a non formal type
- var seen = [self.mpropdef.mproperty.mvirtualtype]
- loop
- if seen.has(bound) then
- seen.add(bound)
- modelbuilder.error(self, "Error: circularity of virtual type definition: {seen.join(" -> ")}")
- return
- end
- seen.add(bound)
- var next = bound.lookup_bound(mmodule, anchor)
- if not next isa MVirtualType then break
- bound = next
- end
- end
-
var ntype = self.n_type
if modelbuilder.resolve_mtype(mmodule, mclassdef, ntype) == null then
mpropdef.bound = null
end
# Check redefinitions
- bound = mpropdef.bound.as(not null)
for p in mpropdef.mproperty.lookup_super_definitions(mmodule, anchor) do
var supbound = p.bound
if supbound == null then break # broken super bound, skip error
nitlanguage / nit.git / commitdiff