Extract patched_spawn to test/helpers.py for reuse

Move pexpect wrapper with improved error messages from test_autocomplete
to shared helpers module, and use it in test_help PTY test.

Author: przadka

test/helpers.py

@@ -8,7 +8,9 @@
 #
 ######################################################################
 import platform
+import sys
 
+import pexpect
 import pytest
 
 _MISSING = object()
@@ -21,6 +23,40 @@ def skip_on_windows(*args, reason='Not supported on Windows', **kwargs):
     )(*args, **kwargs)
 
 
+def patched_spawn(*args, **kwargs):
+    """
+    Wrapper around pexpect.spawn with improved error messages.
+
+    pexpect's errors are confusing to interpret when things go wrong,
+    because it doesn't output the actual stdout by default. This wrapper
+    addresses that inconvenience.
+    """
+    instance = pexpect.spawn(*args, **kwargs)
+
+    def _patch_expect(func):
+        def _wrapper(pattern_list, **kwargs):
+            try:
+                return func(pattern_list, **kwargs)
+            except pexpect.exceptions.TIMEOUT as exc:
+                raise pexpect.exceptions.TIMEOUT(
+                    f'Timeout reached waiting for `{pattern_list}`'
+                ) from exc
+            except pexpect.exceptions.EOF as exc:
+                raise pexpect.exceptions.EOF(f'Received EOF waiting for `{pattern_list}`') from exc
+            except Exception as exc:
+                raise RuntimeError(f'Unexpected error waiting for `{pattern_list}`') from exc
+
+        return _wrapper
+
+    instance.expect = _patch_expect(instance.expect)
+    instance.expect_exact = _patch_expect(instance.expect_exact)
+
+    # capture child shell's output for debugging
+    instance.logfile = sys.stdout.buffer
+
+    return instance
+
+
 def b2_uri_args_v3(bucket_name, path=_MISSING):
     if path is _MISSING:
         return [bucket_name]

test/integration/test_autocomplete.py

@@ -13,7 +13,7 @@
 import pexpect
 import pytest
 
-from test.helpers import skip_on_windows
+from test.helpers import patched_spawn, skip_on_windows
 
 TIMEOUT = 120  # CI can be slow at times when parallelization is extreme
 
@@ -27,41 +27,6 @@
 """
 
 
-def patched_spawn(*args, **kwargs):
-    """
-    Patch pexpect.spawn to improve error messages
-    """
-
-    instance = pexpect.spawn(*args, **kwargs)
-
-    def _patch_expect(func):
-        def _wrapper(pattern_list, **kwargs):
-            try:
-                return func(pattern_list, **kwargs)
-            except pexpect.exceptions.TIMEOUT as exc:
-                raise pexpect.exceptions.TIMEOUT(
-                    f'Timeout reached waiting for `{pattern_list}` to be autocompleted'
-                ) from exc
-            except pexpect.exceptions.EOF as exc:
-                raise pexpect.exceptions.EOF(
-                    f'Received EOF waiting for `{pattern_list}` to be autocompleted'
-                ) from exc
-            except Exception as exc:
-                raise RuntimeError(
-                    f'Unexpected error waiting for `{pattern_list}` to be autocompleted'
-                ) from exc
-
-        return _wrapper
-
-    instance.expect = _patch_expect(instance.expect)
-    instance.expect_exact = _patch_expect(instance.expect_exact)
-
-    # capture child shell's output for debugging
-    instance.logfile = sys.stdout.buffer
-
-    return instance
-
-
 @pytest.fixture(scope='session')
 def bashrc(homedir):
     bashrc_path = homedir / '.bashrc'

test/integration/test_help.py

@@ -12,8 +12,11 @@
 import re
 import subprocess
 
+import pexpect
 import pytest
 
+from test.helpers import patched_spawn
+
 
 def test_help(cli_version):
     p = subprocess.run(
@@ -44,16 +47,14 @@ def test_help_with_tty(cli_version):
 
     NOTE: Works in CI with pytest-xdist, but may not trigger the bug locally.
     """
-    pexpect = pytest.importorskip('pexpect')
-
     # Set up environment - remove LINES/COLUMNS to ensure ioctl is called
     env = os.environ.copy()
     env.pop('LINES', None)
     env.pop('COLUMNS', None)
 
     # Spawn b2 --help with pexpect to create a real PTY
     # This is where the bug would trigger on Python 3.14 without our fix
-    child = pexpect.spawn(
+    child = patched_spawn(
         cli_version,
         ['--help'],
         env=env,
@@ -79,7 +80,6 @@ def test_help_with_tty(cli_version):
     )
 
     # Verify help output contains expected content
-    assert 'b2 <command>' in output or cli_version in output, (
-        f'Help output does not contain expected content.\n'
-        f'Output: {output}'
-    )
+    assert (
+        'b2 <command>' in output or cli_version in output
+    ), f'Help output does not contain expected content.\nOutput: {output}'