fix: corrected a parser error that could cause Argon to crash

Author: jacopodl

argon/lang/parser2/parser2.cpp

@@ -2498,6 +2498,8 @@ Node *Parser::ParseNullCoalescing(Context *context, Node *left) {
     this->Eat(true);
 
     auto *expr = this->ParseExpression(context, PeekPrecedence(TokenType::NULL_COALESCING));
+    if (expr == nullptr)
+        throw ParserException(this->tkcur_.loc, kStandardError[0]);
 
     auto *n_coal = NewNode<Binary>(type_ast_binary_, false, NodeType::NULL_COALESCING);
     if (n_coal == nullptr) {
@@ -2519,6 +2521,9 @@ Node *Parser::ParsePipeline(Context *context, Node *left) {
     this->Eat(true);
 
     auto *right = this->ParseExpression(context, PeekPrecedence(TokenType::PIPELINE));
+    if (right == nullptr)
+        throw ParserException(this->tkcur_.loc, kStandardError[0]);
+
     if (right->node_type == NodeType::CALL) {
         auto *call = (Call *) right;
 
@@ -2696,7 +2701,9 @@ Node *Parser::ParseTernary(Context *context, Node *left) {
 
     this->Eat(true);
 
-    body = (ArObject *) this->ParseExpression(context, PeekPrecedence(TokenType::COMMA));
+    body = this->ParseExpression(context, PeekPrecedence(TokenType::COMMA));
+    if (!body)
+        throw ParserException(this->tkcur_.loc, kStandardError[0]);
 
     this->IgnoreNewLineIF(TokenType::COLON);