fix: crash when input ends with a truncated unicode character

josdejong · Nov 13, 2023 · fe6a1e3 · fe6a1e3
1 parent 36de735
commit fe6a1e3
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/src/parse.test.ts b/src/parse.test.ts
@@ -388,7 +388,15 @@ describe('throw meaningful exceptions', () => {
     },
     { input: 'foo', expectedError: "JSON value expected but got 'f' at position 0" },
     { input: '"\\a"', expectedError: "Invalid escape character '\\a' at position 1" },
-    { input: '"\\u26"', expectedError: "Invalid unicode character '\\u26' at position 1" },
+    { input: '"\\u2', expectedError: "Invalid unicode character '\\u2' at position 1" },
+    { input: '"\\u26', expectedError: "Invalid unicode character '\\u26' at position 1" },
+    { input: '"\\u260', expectedError: "Invalid unicode character '\\u260' at position 1" },
+    {
+      input: '"\\u2605',
+      expectedError: "End of string '\"' expected but reached end of input at position 7"
+    },
+    { input: '{"s \\ud', expectedError: "Invalid unicode character '\\ud' at position 4" },
+    { input: '"\\u26"', expectedError: "Invalid unicode character '\\u26\"' at position 1" },
     { input: '"\\uZ000"', expectedError: "Invalid unicode character '\\uZ000' at position 1" }
   ]
 

diff --git a/src/parse.ts b/src/parse.ts
@@ -300,11 +300,7 @@ export function parse(
   }
 
   function throwInvalidUnicodeCharacter(start: number) {
-    let end = start + 2
-    while (/\w/.test(text[end])) {
-      end++
-    }
-    const chars = text.slice(start, end)
+    const chars = text.slice(start, start + 6)
     throw new SyntaxError(`Invalid unicode character '${chars}' ${pos()}`)
   }