Forward HOME by default (#2907)

fixes #2702

Author: gschaffner

docs/changelog/2702.bugfix.rst

@@ -0,0 +1 @@
+Forward ``HOME`` by default - by :user:`gschaffner`.

src/tox/tox_env/api.py

@@ -218,6 +218,7 @@ def _default_pass_env(self) -> list[str]:
             "CPPFLAGS",  # C++ compiler flags
             "LD_LIBRARY_PATH",  # location of libs
             "LDFLAGS",  # linker flags
+            "HOME",  # needed for `os.path.expanduser()` on non-Windows systems
         ]
         if sys.stdout.isatty():  # if we're on a interactive shell pass on the TERM
             env.append("TERM")

tests/session/cmd/test_show_config.py

@@ -117,7 +117,7 @@ def test_pass_env_config_default(tox_project: ToxProjectCreator, stdout_is_atty:
     expected = (
         ["CC", "CCSHARED", "CFLAGS"]
         + (["COMSPEC"] if is_win else [])
-        + ["CPPFLAGS", "CURL_CA_BUNDLE", "CXX", "LANG", "LANGUAGE", "LDFLAGS", "LD_LIBRARY_PATH"]
+        + ["CPPFLAGS", "CURL_CA_BUNDLE", "CXX", "HOME", "LANG", "LANGUAGE", "LDFLAGS", "LD_LIBRARY_PATH"]
         + (["MSYSTEM", "NUMBER_OF_PROCESSORS", "PATHEXT"] if is_win else [])
         + ["PIP_*", "PKG_CONFIG", "PKG_CONFIG_PATH", "PKG_CONFIG_SYSROOT_DIR"]
         + (["PROCESSOR_ARCHITECTURE"] if is_win else [])