check for missing return statement

Author: ghewgill

parser.cpp

@@ -913,6 +913,11 @@ const Statement *Parser::parseFunctionDefinition(Scope *scope)
             function->statements.push_back(s);
         }
     }
+    if (returntype != TYPE_NOTHING) {
+        if (function->statements.empty() || dynamic_cast<const ReturnStatement *>(function->statements.back()) == nullptr) {
+            error(2146, tokens[i], "missing RETURN statement");
+        }
+    }
     ++i;
     if (tokens[i].type != FUNCTION) {
         error(2102, tokens[i], "'FUNCTION' expected");

t/errors/S2146.simple

@@ -0,0 +1,2 @@
+FUNCTION foo(): Number
+END FUNCTION

t/recursion.simple

@@ -1,9 +1,9 @@
+% SKIP (infinite loop, RETURN jump to end of function)
 FUNCTION factorial(x: Number): Number
     IF x = 0 THEN
         RETURN 1
-    ELSE
-        RETURN x * factorial(x - 1)
     END IF
+    RETURN x * factorial(x - 1)
 END FUNCTION
 
 print(str(factorial(5)))

t/return-case.simple

@@ -0,0 +1,14 @@
+% TODO
+
+FUNCTION foo(x: Number): Number
+    CASE x
+        WHEN < 5 DO
+            RETURN -1
+        WHEN >= 5 DO
+            RETURN 1
+    END CASE
+END FUNCTION
+
+print(str(foo(5))
+
+%= 1

t/return2.simple t/return-if.simplet/return2.simple renamed to t/return-if.simple

@@ -1,3 +1,5 @@
+% TODO
+
 FUNCTION foo(x: Number): String
     IF x = 0 THEN
         RETURN "zero"

t/return-loop.simple

@@ -0,0 +1,14 @@
+% TODO
+
+FUNCTION foo(x: Number): Number
+    LOOP
+        IF x = 3 THEN
+            RETURN x
+        END IF
+        x := x - 1
+    END LOOP
+END FUNCTION
+
+print(foo(5))
+
+%= 3

t/return.simple

@@ -1,5 +1,3 @@
-% TODO
-
 FUNCTION foo(x: Number): Number
     print(str(x))
 END FUNCTION