Typing: add check the type of ConditionOperation in expression

Author: zhangshuwei

phase2/Typing/TypeError.ml

@@ -10,6 +10,7 @@ exception ConstructorAlreadyExists of string
 exception DuplicateLocalVariable of string
 exception IncompatibleTypes of string
 exception InvalidMethodDeclaration of string
+exception InvalidTypeCondOperation of Type.t * Type.t
 exception MethodAlreadyExists of string
 exception UnknownAttribute of string * string
 exception UnknownVariable of string
@@ -20,4 +21,5 @@ exception WrongTypePrefixOperation of string * string
 exception WrongTypePostfixOperation of string
 exception WrongInvokedArgumentsLength of string
 exception WrongTypesAssignOperation of Type.t option * Type.t option
+exception WrongTypeCondOperation of Type.t option
 exception WrongTypesOperation of Type.t option * Type.t option

phase2/Typing/Typing.ml

@@ -237,7 +237,18 @@ let rec verify_expression env current_env e =
       (match op with
       | Op_cor | Op_cand | Op_eq | Op_ne | Op_gt | Op_lt | Op_ge | Op_le -> e.etype <- Some(Primitive(Boolean))
       | Op_or | Op_and | Op_xor | Op_shl | Op_shr | Op_shrr | Op_add | Op_sub | Op_mul | Op_div | Op_mod -> e.etype <- e1.etype)
-  | CondOp (e1,e2,e3) -> () (*TODO*)
+  | CondOp (e1,e2,e3) -> 
+      verify_expression env current_env e1;
+      verify_expression env current_env e2;
+      verify_expression env current_env e3;
+      (* check if e1.etype is boolean and e2.etype equals e3.etype *)
+      if e1.etype <> Some(Primitive(Boolean))
+      then raise(WrongTypeCondOperation(e1.etype))
+      (match e2.etype, e3.etype with
+        | Some(_), None -> ()
+        | None, Some(_) -> ()
+        | Some(t1), Some(t2) -> if t1 <> t2 then raise(InvalidTypeCondOperation(t1, t2)));
+      if e2.etype <> None then e.etype <- e2.etype else e.etype <- e3.etype
   | Cast (t,e1) -> 
       verify_expression env current_env e1;
       e.etype <- Some(t)

phase2/tests/test.java

@@ -19,6 +19,7 @@ public I(int e) {
 	int sr = 5;
 	long l = (long) sr;
 	boolean test = my instanceof I;
+	int condop = (1 == 2) ? 1 : 5;
 	private String func1 (int a) {
 		int b = 1;
 		b += (5+4);