From 6d2e5db4a67cfbe358f585ac0fc082edd7dddc00 Mon Sep 17 00:00:00 2001
From: jwalith4418-Mj <232281058+jwalith4418-Mj@users.noreply.github.com>
Date: Mon, 2 Nov 2026 00:41:00 +0530
Subject: [PATCH] Return an error tuple when parsing empty input

Keep loads() raising its existing ValueError while parse() follows its documented tuple-result contract for empty strings and bytes.

Prepared with AI assistance; contributor review is required before upload.
---
 json5/lib.py      | 2 +-
 tests/lib_test.py | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/json5/lib.py b/json5/lib.py
index c7273d3..91c2b46 100644
--- a/json5/lib.py
+++ b/json5/lib.py
@@ -335,7 +335,7 @@ def parse(
         s = s.decode(encoding)
 
     if not s:
-        raise ValueError('Empty strings are not legal JSON5')
+        return None, 'Empty strings are not legal JSON5', 0
     start = start or 0
     parser = Parser(s, '<string>', pos=start)
     ast, err, pos = parser.parse(
diff --git a/tests/lib_test.py b/tests/lib_test.py
index df83ffd..161928a 100644
--- a/tests/lib_test.py
+++ b/tests/lib_test.py
@@ -533,6 +533,14 @@ def check(self, s, obj, err, pos, consume_trailing=True, start=0):
         self.assertEqual(err, actual_err)
         self.assertEqual(pos, actual_pos)
 
+    def test_parse_empty_input(self):
+        for source in ('', b''):
+            with self.subTest(source=source):
+                self.assertEqual(
+                    json5.parse(source),
+                    (None, 'Empty strings are not legal JSON5', 0),
+                )
+
     def test_parse(self):
         self.check('4', 4, err=None, pos=1)
         self.check('4 ', 4, err=None, pos=2)