From 58789ba25c8f47a530f744e798e1f9d4265f9d68 Mon Sep 17 00:00:00 2001
From: Tomas Zijdemans <tomas.zijdemans@vipps.no>
Date: Thu, 3 Sep 2026 07:07:36 +0200
Subject: [PATCH] fix(jsonc): report unterminated strings as unexpected end of
 input

---
 jsonc/parse.ts      |  7 +++++++
 jsonc/parse_test.ts | 10 ++++++++++
 2 files changed, 17 insertions(+)

diff --git a/jsonc/parse.ts b/jsonc/parse.ts
index 608b65b1503c..21a94e41e2e1 100644
--- a/jsonc/parse.ts
+++ b/jsonc/parse.ts
@@ -156,13 +156,20 @@ class JsoncParser {
           // '"\\\\\\""' => '\\"'
           // '"\\\\\\\\"' => '\\\\'
           let shouldEscapeNext = false;
+          let hasEndOfString = false;
           i++;
           for (; i < this.#length; i++) { // read until find `"`
             if (this.#text[i] === '"' && !shouldEscapeNext) {
+              hasEndOfString = true;
               break;
             }
             shouldEscapeNext = this.#text[i] === "\\" && !shouldEscapeNext;
           }
+          if (!hasEndOfString) {
+            throw new SyntaxError(
+              "Cannot parse JSONC: unexpected end of JSONC input",
+            );
+          }
           yield {
             type: "String",
             sourceText: this.#text.substring(startIndex, i + 1),
diff --git a/jsonc/parse_test.ts b/jsonc/parse_test.ts
index 6d66def312b7..38d8ed8f9080 100644
--- a/jsonc/parse_test.ts
+++ b/jsonc/parse_test.ts
@@ -99,6 +99,16 @@ Deno.test({
       SyntaxError,
       "Cannot parse JSONC: unexpected end of JSONC input",
     );
+    assertInvalidParse(
+      `"abc`,
+      SyntaxError,
+      "Cannot parse JSONC: unexpected end of JSONC input",
+    );
+    assertInvalidParse(
+      `{"a": "b`,
+      SyntaxError,
+      "Cannot parse JSONC: unexpected end of JSONC input",
+    );
     assertInvalidParse(
       `[]100`,
       SyntaxError,