test: isolate HOME and silence expected output in test suite

Point HOME at a private temp dir per suite run so lpb never writes token /
last-project / last-image / state-defaults into the real ~/.localpibox, and
test_remove (which relies on default cfg dirs) can no longer prompt against
real data. _OutputCapture now also redirects the root logger's handler streams
(lpb.py err/warn write via logger too, not just sys.stderr), so expected
error/message noise no longer leaks into CI logs. No real podman/docker/curl
is invoked: images_pull is patched and container ops go through mock_podman.

Author: localpibox

scripts/test_lpb.py

@@ -13,6 +13,7 @@
 import ast
 import builtins
 import importlib.util
+import logging
 import os
 import re
 import shutil
@@ -151,12 +152,52 @@ def reset_mock():
 _module_counter = 0
 _subprocess_orig = None
 _shutil_orig = None
+_ISOLATED_HOME = tempfile.mkdtemp(prefix="lpb_test_home_")
+
+
+class _OutputCapture:
+    """Redirect stdout+stderr to a sink while active (suppresses expected noise).
+
+    Also redirects the root logger's handler streams — lpb.py's err()/warn()
+    write through BOTH print(..., file=sys.stderr) and logger.error, and the
+    logger handler captured the original sys.stderr at import time, so it
+    would bypass a plain sys.stderr swap.
+    """
+
+    def __init__(self):
+        self.out = []
+        self._old = None
+        self._old_streams = None
+
+    def write(self, s):
+        self.out.append(s)
+
+    def flush(self):
+        pass
+
+    def __enter__(self):
+        self._old = (sys.stdout, sys.stderr)
+        sys.stdout, sys.stderr = self, self
+        self._old_streams = [h.stream for h in logging.getLogger().handlers]
+        for h in logging.getLogger().handlers:
+            h.stream = self
+        return self
+
+    def __exit__(self, *exc):
+        sys.stdout, sys.stderr = self._old
+        for h, stream in zip(logging.getLogger().handlers, self._old_streams):
+            h.stream = stream
+        return False
+
 
 def make_module(lpb_path: str | None = None):
     """Import lpb.py with all mocks in place. Each call gets unique module name.
 
     lpb_path: override which lpb source file to import (used by regression
     mutation tests to load a deliberately-broken copy).
+
+    HOME is redirected to a private temp dir, so the module never touches the
+    real ~/.localpibox (token / last-project / last-image / state defaults).
     """
     global _module_counter, _subprocess_orig, _shutil_orig
     _module_counter += 1
@@ -169,10 +210,12 @@ def make_module(lpb_path: str | None = None):
     subprocess.run = mock_run
     shutil.which = mock_which
 
-    # Remove LPB_* env vars so tests get clean defaults
+    # Remove LPB_* env vars so tests get clean defaults, and point HOME at a
+    # private temp dir so the module's default paths are isolated per run.
     for key in list(os.environ.keys()):
         if key.startswith("LPB_"):
             os.environ.pop(key, None)
+    os.environ["HOME"] = _ISOLATED_HOME
 
     # Use unique name to bypass sys.modules cache
     mod_name = f"lpb_test_{_module_counter}_{id(make_module)}"
@@ -243,7 +286,8 @@ def test_remove():
     mod = make_module()
     mod.parse_cli(["--remove"])
     mod.apply_overrides()
-    mod.cmd_remove()
+    with _OutputCapture():
+        mod.cmd_remove()
     assert not MOCK_STATE["exists"], "container should be removed"
     print("  PASS\n")
 
@@ -278,26 +322,28 @@ def test_logs_missing():
     mod = make_module()
     mod.parse_cli(["--logs"])
     mod.apply_overrides()
-    try:
-        mod.cmd_logs()
-    except SystemExit:
-        pass
+    with _OutputCapture():
+        try:
+            mod.cmd_logs()
+        except SystemExit:
+            pass
     print("  PASS\n")
 
 
 def test_unknown_flag():
     print("TEST: --foo-bar → error")
     reset_mock()
     mod = make_module()
-    try:
-        mod.parse_cli(["--foo-bar"])
-        mod.apply_overrides()
-        mod.cmd_run()
-        assert False, "should have raised an error"
-    except (SystemExit, mod.DevstackError) as e:
-        # DevstackError (new) or SystemExit(code=1) (legacy path)
-        if isinstance(e, SystemExit):
-            assert e.code == 1
+    with _OutputCapture():
+        try:
+            mod.parse_cli(["--foo-bar"])
+            mod.apply_overrides()
+            mod.cmd_run()
+            assert False, "should have raised an error"
+        except (SystemExit, mod.DevstackError) as e:
+            # DevstackError (new) or SystemExit(code=1) (legacy path)
+            if isinstance(e, SystemExit):
+                assert e.code == 1
     print("  PASS\n")
 
 
@@ -571,7 +617,8 @@ def test_cmd_remove_with_dirs():
         orig_input = builtins.input
         builtins.input = lambda prompt="": "y"
         try:
-            mod.cmd_remove()
+            with _OutputCapture():
+                mod.cmd_remove()
         finally:
             builtins.input = orig_input
         assert not MOCK_STATE["exists"], "container should be removed"
@@ -596,7 +643,8 @@ def test_cmd_remove_abort():
         orig_input = builtins.input
         builtins.input = lambda prompt="": "n"
         try:
-            mod.cmd_remove()
+            with _OutputCapture():
+                mod.cmd_remove()
         finally:
             builtins.input = orig_input
         assert os.path.exists(state), "state dir must survive an aborted remove"
@@ -620,9 +668,10 @@ def test_cmd_update_runs():
     mod.ContainerClient.images_pull = lambda self, name: pulled.append(name) or 0
     mod.parse_cli(["--update"])
     mod.apply_overrides()
-    mod.cmd_update()
+    with _OutputCapture():
+        mod.cmd_update()
     assert pulled, f"expected image pulls, got {pulled}"
-    print(f"  pulled: {pulled}")
+    print(f"  pulled: {pulled} (via mocked images_pull)")
     print("  PASS\n")
 
 
@@ -649,7 +698,8 @@ def spy_containers_run(*a, **kw):
         return ("cid123", "cid123", "", 0)
 
     mod.ContainerClient.containers_run = spy_containers_run
-    mod.cmd_run()
+    with _OutputCapture():
+        mod.cmd_run()
     assert mod.cfg.project_name == "tmp"
     env_vars = captured.get("env", [])
     env_str = "\n".join(env_vars)