modelbuilder: add `check_subtype` and `check_sametype`

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/modelbuilder_base.nit b/src/modelbuilder_base.nit
index b940049..6cbcbef 100644 (file)
--- a/src/modelbuilder_base.nit
+++ b/src/modelbuilder_base.nit
@@ -311,7 +311,7 @@ class ModelBuilder
                                if mt == null then return null # forward error
                                var anchor
                                if mclassdef != null then anchor = mclassdef.bound_mtype else anchor = null
-                               if not mt.is_subtype(mmodule, anchor, bound) then
+                               if not check_subtype(nt, mmodule, anchor, mt, bound) then
                                        error(nt, "Type error: expected {bound}, got {mt}")
                                        return null
                                end
@@ -320,6 +320,26 @@ class ModelBuilder
                ntype.checked_mtype = true
                return mtype
        end
+
+       # Check that `sub` is a subtype of `sup`.
+       # Do not display an error message.
+       #
+       # This method is used a an entry point for the modelize phase to test static subtypes.
+       # Some refinements could redefine it to collect statictics.
+       fun check_subtype(node: ANode, mmodule: MModule, anchor: nullable MClassType, sub, sup: MType): Bool
+       do
+               return sub.is_subtype(mmodule, anchor, sup)
+       end
+
+       # Check that `sub` and `sup` are equvalent types.
+       # Do not display an error message.
+       #
+       # This method is used a an entry point for the modelize phase to test static equivalent types.
+       # Some refinements could redefine it to collect statictics.
+       fun check_sametype(node: ANode, mmodule: MModule, anchor: nullable MClassType, sub, sup: MType): Bool
+       do
+               return sub.is_subtype(mmodule, anchor, sup) and sup.is_subtype(mmodule, anchor, sub)
+       end
 end
 
 redef class AType

diff --git a/src/modelize/modelize_property.nit b/src/modelize/modelize_property.nit
index d8fd96d..42dee1e 100644 (file)
--- a/src/modelize/modelize_property.nit
+++ b/src/modelize/modelize_property.nit
@@ -829,18 +829,21 @@ redef class AMethPropdef
                                for i in [0..mysignature.arity[ do
                                        var myt = mysignature.mparameters[i].mtype
                                        var prt = msignature.mparameters[i].mtype
-                                       if not myt.is_subtype(mmodule, mclassdef.bound_mtype, prt) or
-                                                       not prt.is_subtype(mmodule, mclassdef.bound_mtype, myt) then
-                                               modelbuilder.error(nsig.n_params[i], "Redef Error: Wrong type for parameter `{mysignature.mparameters[i].name}'. found {myt}, expected {prt} as in {mpropdef.mproperty.intro}.")
+                                       var node = nsig.n_params[i]
+                                       if not modelbuilder.check_sametype(node, mmodule, mclassdef.bound_mtype, myt, prt) then
+                                               modelbuilder.error(node, "Redef Error: Wrong type for parameter `{mysignature.mparameters[i].name}'. found {myt}, expected {prt} as in {mpropdef.mproperty.intro}.")
                                        end
                                end
                        end
                        if precursor_ret_type != null then
+                               var node: nullable ANode = null
+                               if nsig != null then node = nsig.n_type
+                               if node == null then node = self
                                if ret_type == null then
                                        # Inherit the return type
                                        ret_type = precursor_ret_type
-                               else if not ret_type.is_subtype(mmodule, mclassdef.bound_mtype, precursor_ret_type) then
-                                       modelbuilder.error(nsig.n_type.as(not null), "Redef Error: Wrong return type. found {ret_type}, expected {precursor_ret_type} as in {mpropdef.mproperty.intro}.")
+                               else if not modelbuilder.check_subtype(node, mmodule, mclassdef.bound_mtype, ret_type, precursor_ret_type) then
+                                       modelbuilder.error(node, "Redef Error: Wrong return type. found {ret_type}, expected {precursor_ret_type} as in {mpropdef.mproperty.intro}.")
                                end
                        end
                end
@@ -1162,21 +1165,20 @@ redef class AAttrPropdef
                                for i in [0..mysignature.arity[ do
                                        var myt = mysignature.mparameters[i].mtype
                                        var prt = msignature.mparameters[i].mtype
-                                       if not myt.is_subtype(mmodule, mclassdef.bound_mtype, prt) or
-                                                       not prt.is_subtype(mmodule, mclassdef.bound_mtype, myt) then
-                                               var node: ANode
-                                               if nsig != null then node = nsig else node = self
+                                       var node: ANode
+                                       if nsig != null then node = nsig else node = self
+                                       if not modelbuilder.check_sametype(node, mmodule, mclassdef.bound_mtype, myt, prt) then
                                                modelbuilder.error(node, "Redef Error: Wrong type for parameter `{mysignature.mparameters[i].name}'. found {myt}, expected {prt}.")
                                        end
                                end
                        end
                        if precursor_ret_type != null then
+                               var node: ANode
+                               if nsig != null then node = nsig else node = self
                                if ret_type == null then
                                        # Inherit the return type
                                        ret_type = precursor_ret_type
-                               else if not ret_type.is_subtype(mmodule, mclassdef.bound_mtype, precursor_ret_type) then
-                                       var node: ANode
-                                       if nsig != null then node = nsig else node = self
+                               else if not modelbuilder.check_subtype(node, mmodule, mclassdef.bound_mtype, ret_type, precursor_ret_type) then
                                        modelbuilder.error(node, "Redef Error: Wrong return type. found {ret_type}, expected {precursor_ret_type}.")
                                end
                        end
@@ -1283,7 +1285,7 @@ redef class ATypePropdef
                                modelbuilder.warning(n_type, "refine-type", "Redef Error: a virtual type cannot be refined.")
                                break
                        end
-                       if not bound.is_subtype(mmodule, anchor, supbound) then
+                       if not modelbuilder.check_subtype(n_type, mmodule, anchor, bound, supbound) then
                                modelbuilder.error(n_type, "Redef Error: Wrong bound type. Found {bound}, expected a subtype of {supbound}, as in {p}.")
                                break
                        end