Add check of element type of array

Ref. #311

rflx/model.py

@@ -405,14 +405,30 @@ def __init__(self, identifier: StrID, element_type: Type, location: Location = N
         super().__init__(identifier, location)
         self.element_type = element_type
 
+        if not isinstance(element_type, Scalar) and not (
+            isinstance(element_type, Message) and element_type.structure
+        ):
+            self.error.append(
+                f'invalid element type of array "{self.name}"',
+                Subsystem.MODEL,
+                Severity.ERROR,
+                location,
+            )
+            self.error.append(
+                f'type "{element_type.name}" must be scalar or non-null message',
+                Subsystem.MODEL,
+                Severity.INFO,
+                element_type.location,
+            )
+
     @property
     def element_size(self) -> Expr:
         return Length(self.element_type.name)
 
 
 class Opaque(Composite):
-    def __init__(self) -> None:
-        super().__init__(INTERNAL_PACKAGE * "Opaque")
+    def __init__(self, location: Location = None) -> None:
+        super().__init__(INTERNAL_PACKAGE * "Opaque", location)
 
     @property
     def element_size(self) -> Expr:
@@ -1721,8 +1737,10 @@ def qualified_type_name(name: ID, package: ID) -> ID:
     return name
 
 
+OPAQUE = Opaque(location=Location((0, 0), Path(str(BUILTINS_PACKAGE)), (0, 0)))
+
 INTERNAL_TYPES = {
-    Opaque().identifier: Opaque(),
+    OPAQUE.identifier: OPAQUE,
 }
 
 BOOLEAN = Enumeration(

rflx/parser/ast.py

@@ -64,6 +64,18 @@ def __init__(self, items: List[StrID]) -> None:
         self.items = list(map(ID, items))
 
 
+class ReferenceSpec(Type):
+    pass
+
+
+class ArraySpec(Type):
+    def __init__(
+        self, identifier: StrID, element_type: ReferenceSpec, location: Location = None
+    ) -> None:
+        super().__init__(identifier, location)
+        self.element_type = element_type
+
+
 class MessageSpec(Type):
     def __init__(
         self, identifier: StrID, components: List[Component], location: Location = None
@@ -98,10 +110,6 @@ def __init__(
         )
 
 
-class ReferenceSpec(Type):
-    pass
-
-
 class Specification(SyntaxTree):
     def __init__(self, context: ContextSpec, package: PackageSpec) -> None:
         self.context = context

rflx/parser/grammar.py

@@ -57,9 +57,10 @@
     Variable,
 )
 from rflx.identifier import ID
-from rflx.model import Array, Enumeration, ModularInteger, RangeInteger, Type, qualified_type_name
+from rflx.model import Enumeration, ModularInteger, RangeInteger, Type, qualified_type_name
 
 from .ast import (
+    ArraySpec,
     Component,
     ContextSpec,
     DerivationSpec,
@@ -616,7 +617,7 @@ def parse_type(string: str, location: int, tokens: ParseResults) -> Type:
     if tokens[3] == "new":
         return DerivationSpec(identifier, tokens[4], locn)
     if tokens[3] == "array of":
-        return Array(
+        return ArraySpec(
             identifier,
             ReferenceSpec(qualified_type_name(tokens[4], package), tokens[4].location),
             locn,

rflx/parser/parser.py

@@ -14,7 +14,7 @@
     pop_source,
     push_source,
 )
-from rflx.expression import UNDEFINED, Number
+from rflx.expression import UNDEFINED
 from rflx.identifier import ID
 from rflx.model import (
     BUILTIN_TYPES,
@@ -38,7 +38,15 @@
 )
 
 from . import grammar
-from .ast import Component, DerivationSpec, MessageSpec, PackageSpec, RefinementSpec, Specification
+from .ast import (
+    ArraySpec,
+    Component,
+    DerivationSpec,
+    MessageSpec,
+    PackageSpec,
+    RefinementSpec,
+    Specification,
+)
 
 log = logging.getLogger(__name__)
 
@@ -165,7 +173,7 @@ def __evaluate_types(self, spec: Specification, error: RecordFluxError) -> None:
                 if isinstance(t, Scalar):
                     new_type = t
 
-                elif isinstance(t, Array):
+                elif isinstance(t, ArraySpec):
                     new_type = create_array(t, self.__types)
 
                 elif isinstance(t, MessageSpec):
@@ -191,7 +199,7 @@ def message_types(types: Mapping[ID, Type]) -> Mapping[ID, Message]:
     return {n: m for n, m in types.items() if isinstance(m, Message)}
 
 
-def create_array(array: Array, types: Mapping[ID, Type]) -> Array:
+def create_array(array: ArraySpec, types: Mapping[ID, Type]) -> Array:
     array.element_type.identifier = ID(
         array.element_type.full_name.replace("__PACKAGE__", str(array.package)), array.location
     )
@@ -222,7 +230,7 @@ def create_array(array: Array, types: Mapping[ID, Type]) -> Array:
             )
             error.propagate()
 
-    return Array(array.identifier, element_type)
+    return Array(array.identifier, element_type, array.location)
 
 
 def create_message(message: MessageSpec, types: Mapping[ID, Type]) -> Message:

tests/test_model.py

@@ -29,6 +29,7 @@
     BUILTIN_TYPES,
     FINAL,
     INITIAL,
+    OPAQUE,
     Array,
     DerivedMessage,
     Enumeration,
@@ -326,6 +327,24 @@ def test_enumeration_invalid_literal() -> None:
     )
 
 
+def test_array_invalid_element_type() -> None:
+    assert_type_error(
+        Array("P.A", Array("P.B", MODULAR_INTEGER, Location((3, 4))), Location((5, 4))),
+        r'^<stdin>:5:4: model: error: invalid element type of array "A"\n'
+        r'<stdin>:3:4: model: info: type "B" must be scalar or non-null message$',
+    )
+    assert_type_error(
+        Array("P.A", Message("P.B", [], {}, Location((3, 4))), Location((5, 4))),
+        r'^<stdin>:5:4: model: error: invalid element type of array "A"\n'
+        r'<stdin>:3:4: model: info: type "B" must be scalar or non-null message$',
+    )
+    assert_type_error(
+        Array("P.A", OPAQUE, Location((5, 4))),
+        r'^<stdin>:5:4: model: error: invalid element type of array "A"\n'
+        r'__BUILTINS__:0:0: model: info: type "Opaque" must be scalar or non-null message$',
+    )
+
+
 def test_message_incorrect_name() -> None:
     with pytest.raises(
         RecordFluxError, match='^<stdin>:10:8: model: error: unexpected format of type name "M"$'

tests/test_parser.py

@@ -30,7 +30,6 @@
 from rflx.model import (
     FINAL,
     INITIAL,
-    Array,
     DerivedMessage,
     Enumeration,
     Field,
@@ -43,6 +42,7 @@
 )
 from rflx.parser import grammar, parser
 from rflx.parser.ast import (
+    ArraySpec,
     ContextSpec,
     DerivationSpec,
     MessageSpec,
@@ -815,7 +815,7 @@ def test_array_type_spec() -> None:
                 "Array_Type",
                 [
                     ModularInteger("__PACKAGE__.Byte", Number(256)),
-                    Array("__PACKAGE__.Bytes", ReferenceSpec("__PACKAGE__.Byte")),
+                    ArraySpec("__PACKAGE__.Bytes", ReferenceSpec("__PACKAGE__.Byte")),
                     MessageSpec(
                         "__PACKAGE__.Foo",
                         [
@@ -827,7 +827,7 @@ def test_array_type_spec() -> None:
                             Component("Bytes", "Bytes"),
                         ],
                     ),
-                    Array("__PACKAGE__.Bar", ReferenceSpec("__PACKAGE__.Foo")),
+                    ArraySpec("__PACKAGE__.Bar", ReferenceSpec("__PACKAGE__.Foo")),
                 ],
             ),
         )