Add SequenceNode to type checker

Author: antonmedv

checker/checker.go

@@ -178,6 +178,8 @@ func (v *checker) visit(node ast.Node) Nature {
 		nt = v.PointerNode(n)
 	case *ast.VariableDeclaratorNode:
 		nt = v.VariableDeclaratorNode(n)
+	case *ast.SequenceNode:
+		nt = v.SequenceNode(n)
 	case *ast.ConditionalNode:
 		nt = v.ConditionalNode(n)
 	case *ast.ArrayNode:
@@ -1181,6 +1183,17 @@ func (v *checker) VariableDeclaratorNode(node *ast.VariableDeclaratorNode) Natur
 	return exprNature
 }
 
+func (v *checker) SequenceNode(node *ast.SequenceNode) Nature {
+	if len(node.Nodes) == 0 {
+		return v.error(node, "empty sequence expression")
+	}
+	var last Nature
+	for _, node := range node.Nodes {
+		last = v.visit(node)
+	}
+	return last
+}
+
 func (v *checker) lookupVariable(name string) (varScope, bool) {
 	for i := len(v.varScopes) - 1; i >= 0; i-- {
 		if v.varScopes[i].name == name {

checker/checker_test.go

@@ -669,6 +669,14 @@ invalid operation: == (mismatched types int and string) (1:33)
 invalid operation: > (mismatched types string and int) (1:30)
  | 1..3 | map("str") | filter(# > 1)
  | .............................^
+`,
+		},
+		{
+			`1; 2 + true; 3`,
+			`
+invalid operation: + (mismatched types int and bool) (1:6)
+ | 1; 2 + true; 3
+ | .....^
 `,
 		},
 	}