checker: check types for bitwise right shift

vlib/v/checker/check_types.v

@@ -4,6 +4,7 @@
 module checker
 
 import v.table
+import v.token
 
 pub fn (c &Checker) check_types(got, expected table.Type) bool {
 	t := c.table
@@ -126,6 +127,18 @@ pub fn (c &Checker) check_types(got, expected table.Type) bool {
 	return false
 }
 
+[inline]
+fn (c &Checker) check_shift(left_type, right_type table.Type, left_pos, right_pos token.Position) table.Type {
+	if !left_type.is_int() {
+		c.error('cannot shift type ${c.table.get_type_symbol(right_type).name} into non-integer type ${c.table.get_type_symbol(left_type).name}', left_pos)
+		return table.void_type
+	} else if !right_type.is_int() {
+		c.error('cannot shift non-integer type ${c.table.get_type_symbol(right_type).name} into type ${c.table.get_type_symbol(left_type).name}', right_pos)
+		return table.void_type
+	}
+	return left_type
+}
+
 pub fn (c &Checker) promote(left_type, right_type table.Type) table.Type {
 	if left_type.is_ptr() || left_type.is_pointer() {
 		if right_type.is_int() {

vlib/v/checker/checker.v

@@ -524,14 +524,13 @@ pub fn (mut c Checker) infix_expr(mut infix_expr ast.InfixExpr) table.Type {
 				s := left.name.replace('array_', '[]')
 				c.error('cannot append `$right.name` to `$s`', right_pos)
 				return table.void_type
-			} else if !left.is_int() {
-				c.error('cannot shift type $right.name into non-integer type $left.name', left_pos)
-				return table.void_type
-			} else if !right.is_int() {
-				c.error('cannot shift non-integer type $right.name into type $left.name', right_pos)
-				return table.void_type
+			} else {
+				return c.check_shift(left_type, right_type, left_pos, right_pos)
 			}
 		}
+		.right_shift {
+			return c.check_shift(left_type, right_type, left_pos, right_pos)
+		}
 		.key_is {
 			type_expr := infix_expr.right as ast.Type
 			typ_sym := c.table.get_type_symbol(type_expr.typ)

vlib/v/checker/tests/rshift_op_wrong_left_type_err.out

@@ -0,0 +1,5 @@
+vlib/v/checker/tests/rshift_op_wrong_left_type_err.v:2:2: error: cannot shift type any_int into non-integer type any_float 
+    1 | fn main() {
+    2 |     0.5 >> 1
+      |     ~~~
+    3 | }

vlib/v/checker/tests/rshift_op_wrong_left_type_err.vv

@@ -0,0 +1,3 @@
+fn main() {
+	0.5 >> 1
+}

vlib/v/checker/tests/rshift_op_wrong_right_type_err.out

@@ -0,0 +1,5 @@
+vlib/v/checker/tests/rshift_op_wrong_right_type_err.v:2:7: error: cannot shift non-integer type any_float into type any_int 
+    1 | fn main() {
+    2 |     1 >> 0.5
+      |          ~~~
+    3 | }

vlib/v/checker/tests/rshift_op_wrong_right_type_err.vv

@@ -0,0 +1,3 @@
+fn main() {
+	1 >> 0.5
+}