Ensure Ada strings don't contain newlines

Ref. #907

rflx/ada.py

@@ -593,7 +593,7 @@ def precedence(self) -> Precedence:
 
 class String(Aggregate):
     def __init__(self, data: str) -> None:
-        data = data.replace('"', '""')
+        data = data.replace('"', '""').replace("\n", " ")
         super().__init__(*[Number(ord(d)) for d in data])
         self.data = data
 

rflx/expression.py

@@ -2787,7 +2787,9 @@ def _update_str(self) -> None:
 
     def _check_type_subexpr(self) -> RecordFluxError:
         error = RecordFluxError()
+
         resulttype: rty.Type = rty.Any()
+
         for _, expr in self.choices:
             error += expr.check_type_instance(rty.Any)
             resulttype = resulttype.common_type(expr.type_)
@@ -2815,6 +2817,19 @@ def _check_type_subexpr(self) -> RecordFluxError:
 
         error += self.expr.check_type_instance(rty.Any)
         error.propagate()
+
+        if not isinstance(self.expr.type_, (rty.AnyInteger, rty.Enumeration)):
+            error.extend(
+                [
+                    (
+                        f'invalid discrete choice type "{self.expr.type_}"',
+                        Subsystem.MODEL,
+                        Severity.ERROR,
+                        self.expr.location,
+                    ),
+                ]
+            )
+
         self.type_ = resulttype
 
         return error

tests/unit/expression_test.py

@@ -2520,6 +2520,11 @@ def test_case_type() -> None:
         r'"__BUILTINS__::Boolean"\n'
         r'model: warning: conflicting with "1" which has type type universal integer \(1\)$',
     )
+    assert_type_error(
+        Case(Opaque(Variable("X", type_=rty.Message("A"))), [([ID("V")], Number(1))]),
+        r'^model: error: invalid discrete choice type "sequence type "__INTERNAL__::Opaque" '
+        r'with element integer type "Byte" \(0 .. 255\)"$',
+    )
 
 
 def test_case_simplified() -> None: