fix: a fake stdout might not have isatty

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/test_misc.py b/tests/test_misc.py
index 455a3bc1..d489f171 100644
--- a/tests/test_misc.py
+++ b/tests/test_misc.py
@@ -6,6 +6,7 @@
 from __future__ import annotations
 
 import sys
+from typing import Any
 from unittest import mock
 
 import pytest
@@ -165,3 +166,19 @@ def test_stdout_link_tty() -> None:
 def test_stdout_link_not_tty() -> None:
     # Without mocking isatty, it reports False in a pytest suite.
     assert stdout_link("some text", "some url") == "some text"
+
+
+def test_stdout_link_with_fake_stdout() -> None:
+    # If stdout is another object, we should still be ok.
+    class FakeStdout:
+        """New stdout, has .write(), but not .isatty()."""
+        def __init__(self, f: Any) -> None:
+            self.f = f
+
+        def write(self, data: str) -> Any:
+            """Write through to the underlying file."""
+            return self.f.write(data)
+
+    with mock.patch.object(sys, "stdout", FakeStdout(sys.stdout)):
+        link = stdout_link("some text", "some url")
+    assert link == "some text"