Add check for name conflicts between field names and enum literals

Ref. #309

rflx/model.py

@@ -669,6 +669,28 @@ def __verify(self) -> None:
                 ]
             )
 
+        name_conflicts = [
+            (f, l)
+            for f in type_fields
+            for l in qualified_literals(self.types, self.package)
+            if f.identifier == l
+        ]
+
+        if name_conflicts:
+            conflicting_field, conflicting_literal = name_conflicts.pop(0)
+            self.error.append(
+                f'name conflict for field "{conflicting_field.name}" in "{self.identifier}"',
+                Subsystem.MODEL,
+                Severity.ERROR,
+                conflicting_field.identifier.location,
+            )
+            self.error.append(
+                "conflicting enumeration literal",
+                Subsystem.MODEL,
+                Severity.INFO,
+                conflicting_literal.location,
+            )
+
         self.error.propagate()
 
         for f in structure_fields:

tests/test_model.py

@@ -379,6 +379,29 @@ def test_message_ambiguous_first_field() -> None:
     )
 
 
+def test_message_name_conflict_field_enum() -> None:
+    t = Enumeration(
+        "P.T",
+        [(ID("X", Location((3, 27))), Number(1)), (ID("Y", Location((3, 32))), Number(2))],
+        Number(8),
+        False,
+    )
+
+    structure = [
+        Link(INITIAL, Field("X")),
+        Link(Field("X"), FINAL),
+    ]
+
+    types = {Field(ID("X", Location((5, 6)))): t}
+
+    assert_message_model_error(
+        structure,
+        types,
+        '^<stdin>:5:6: model: error: name conflict for field "X" in "P.M"\n'
+        "<stdin>:3:27: model: info: conflicting enumeration literal",
+    )
+
+
 def test_message_duplicate_link() -> None:
     t = ModularInteger("P.T", Number(2))
     x = Field(ID("X", location=Location((1, 5))))