From e541294ab21a039fce0bc5b6556d31a02bf05882 Mon Sep 17 00:00:00 2001
From: HyukWoo Park <hyukwoo.park@samsung.com>
Date: Tue, 5 Nov 2024 21:30:42 +0900
Subject: [PATCH] Fix a parsing bug in nullish-coalescing

Signed-off-by: HyukWoo Park <hyukwoo.park@samsung.com>
---
 src/parser/esprima_cpp/esprima.cpp | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/src/parser/esprima_cpp/esprima.cpp b/src/parser/esprima_cpp/esprima.cpp
index e6c910768..5cd999290 100644
--- a/src/parser/esprima_cpp/esprima.cpp
+++ b/src/parser/esprima_cpp/esprima.cpp
@@ -2964,10 +2964,19 @@ class Parser {
 
         ASTNode expr = this->inheritCoverGrammar(builder, &Parser::parseExponentiationExpression<ASTBuilder>);
 
+        bool allowAndOr = true;
+        bool allowNullishCoalescing = true;
         ALLOC_TOKEN(token);
         *token = this->lookahead;
         int prec = this->binaryPrecedence(token);
         if (prec > 0) {
+            if (token->type == Token::PunctuatorToken) {
+                if (token->valuePunctuatorKind == PunctuatorKind::LogicalAnd || token->valuePunctuatorKind == PunctuatorKind::LogicalOr) {
+                    allowNullishCoalescing = false;
+                } else if (token->valuePunctuatorKind == PunctuatorKind::NullishCoalescing) {
+                    allowAndOr = false;
+                }
+            }
             this->nextToken();
 
             token->prec = prec;
@@ -2995,6 +3004,20 @@ class Parser {
                     break;
                 }
 
+                if (this->lookahead.type == Token::PunctuatorToken) {
+                    if (!allowAndOr && (this->lookahead.valuePunctuatorKind == PunctuatorKind::LogicalAnd || this->lookahead.valuePunctuatorKind == PunctuatorKind::LogicalOr)) {
+                        this->throwError(Messages::CannotChainLogicalWithNullish);
+                    } else if (!allowNullishCoalescing && (this->lookahead.valuePunctuatorKind == PunctuatorKind::NullishCoalescing)) {
+                        this->throwError(Messages::CannotChainLogicalWithNullish);
+                    }
+
+                    if (this->lookahead.valuePunctuatorKind == PunctuatorKind::LogicalAnd || this->lookahead.valuePunctuatorKind == PunctuatorKind::LogicalOr) {
+                        allowNullishCoalescing = false;
+                    } else if (this->lookahead.valuePunctuatorKind == PunctuatorKind::NullishCoalescing) {
+                        allowAndOr = false;
+                    }
+                }
+
                 // Reduce: make a binary expression from the three topmost entries.
                 while ((stack.size() > 1) && (prec <= tokenStack.back().prec)) {
                     right = stack.back();
@@ -3084,9 +3107,6 @@ class Parser {
             case LogicalAnd:
                 return builder.createBinaryExpressionLogicalAndNode(left, right);
             case NullishCoalescing:
-                if (left->isLogicalOperation() || right->isLogicalOperation()) {
-                    this->throwError(Messages::CannotChainLogicalWithNullish);
-                }
                 return builder.createBinaryExpressionNullishCoalescingNode(left, right);
             default:
                 RELEASE_ASSERT_NOT_REACHED();