From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Wed, 18 Jun 2025 04:19:43 +0000 (+0200)
Subject: [3.14] gh-127146: Emscripten: Fix pathlib glob_dotdot test (GH-135624) (#135653)
X-Git-Tag: v3.14.0b4~154
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9f63a54aec6fa9bc22382aa1a5a6e47ec12fca23;p=thirdparty%2FPython%2Fcpython.git

[3.14] gh-127146: Emscripten: Fix pathlib glob_dotdot test (GH-135624) (#135653)

The Emscripten path resolver uses the same mechanism for resolving `..`
at a file system root as for resolving symlinks. This is because
roots don't store their mountpoints. If the parent of a node is itself,
it is a root but it might be a mountpoint in some other file system.

If a path has enough `..`'s at the root, it will return ELOOP.
Enough turns out to be 49.
(cherry picked from commit e4ccd46bf75fff2938d7c21c7284e49b0ab795b0)

Co-authored-by: Hood Chatham <roberthoodchatham@gmail.com>
---

diff --git a/Lib/test/test_pathlib/test_pathlib.py b/Lib/test/test_pathlib/test_pathlib.py
index 13356b4cfe08..b2e2cdb3338b 100644
--- a/Lib/test/test_pathlib/test_pathlib.py
+++ b/Lib/test/test_pathlib/test_pathlib.py
@@ -2954,7 +2954,13 @@ class PathTest(PurePathTest):
         else:
             # ".." segments are normalized first on Windows, so this path is stat()able.
             self.assertEqual(set(p.glob("xyzzy/..")), { P(self.base, "xyzzy", "..") })
-        self.assertEqual(set(p.glob("/".join([".."] * 50))), { P(self.base, *[".."] * 50)})
+        if sys.platform == "emscripten":
+            # Emscripten will return ELOOP if there are 49 or more ..'s.
+            # Can remove when https://github.com/emscripten-core/emscripten/pull/24591 is merged.
+            NDOTDOTS = 48
+        else:
+            NDOTDOTS = 50
+        self.assertEqual(set(p.glob("/".join([".."] * NDOTDOTS))), { P(self.base, *[".."] * NDOTDOTS)})
 
     def test_glob_inaccessible(self):
         P = self.cls