From ed2d48a3625c41dbec9c5418b66bd5a686d40071 Mon Sep 17 00:00:00 2001
From: Vincent Gao <gaobing1230@gmail.com>
Date: Sat, 20 Jun 2026 18:58:59 +0200
Subject: [PATCH] Fix fragment with path structure misparsed as a query (#172)

A fragment with no '?' was treated as a query whenever it contained '=',
so a fragment like '#/foo=123' was parsed as a query and its '/' was
percent-encoded, round-tripping to '#%2Ffoo=123' instead of '#/foo=123'.

Only treat such a fragment as a query when '=' precedes any '/' (or there
is no '/'); a '/' before the first '=' signals path structure. Fragments
like '#woofs=dogs' stay queries; '#/foo=123' and '#a/b=c' are now paths.
---
 furl/furl.py       | 13 +++++++++++--
 tests/test_furl.py | 10 ++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/furl/furl.py b/furl/furl.py
index cd6d710..183c848 100644
--- a/furl/furl.py
+++ b/furl/furl.py
@@ -1213,9 +1213,18 @@ def load(self, fragment):
         elif len(toks) == 1:
             # Does this fragment look like a path or a query? Default to
             # path.
-            if '=' in fragment:  # Query example: '#woofs=dogs'.
+            #
+            # A '=' alone isn't enough to call it a query: a fragment like
+            # '#/foo=123' is a path that happens to contain '=' (and its '/'
+            # would wrongly get percent-encoded if treated as a query key).
+            # Only treat it as a query when '=' comes before any '/', or no
+            # '/' is present at all. A '/' before the first '=' signals path
+            # structure. See issue #172.
+            if '=' in fragment and (
+                '/' not in fragment or fragment.find('=') < fragment.find('/')
+            ):  # Query example: '#woofs=dogs'.
                 self._query.load(fragment)
-            else:  # Path example: '#supinthisthread'.
+            else:  # Path example: '#supinthisthread', '#/foo=123'.
                 self._path.load(fragment)
         else:
             # Does toks[1] actually look like a query? Like 'a=a' or
diff --git a/tests/test_furl.py b/tests/test_furl.py
index bc268c8..d223136 100644
--- a/tests/test_furl.py
+++ b/tests/test_furl.py
@@ -989,6 +989,16 @@ def test_load(self):
                   {'a': 'a', 'hok sprm': None}),
                  ('/sch/toot?a=a&hok sprm', '/sch/toot',
                   {'a': 'a', 'hok sprm': None}),
+                 # A '=' without a '?' is only a query when '=' precedes any
+                 # '/'. A '/' before the first '=' means the fragment is a
+                 # path that merely contains '=' and its '/' must not be
+                 # percent-encoded as a query key would be (issue #172).
+                 ('/foo=123', '/foo=123', {}),
+                 ('a/b=c', 'a/b=c', {}),
+                 ('/a=1&b=2', '/a=1&b=2', {}),
+                 ('/foo=123/bar=456', '/foo=123/bar=456', {}),
+                 # '=' before any '/' still parses as a query (unchanged).
+                 ('woofs=dogs', '', {'woofs': 'dogs'}),
                  ]
 
         for fragment, path, query in comps: