Fix python path resolution on linux (#1196)

Author: Gitznik

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Update `pipx run` on scripts using `/// script` and no `run` table following the updated version of PEP 723 (#1180)
 - Avoid repeated exception logging in a few rare cases (#1192)
 - Include `tomli` into `pipx.pyz` (zipapp) so that it can be executed with Python 3.10 or earlier (#1142)
+- Fix resolving the python executable path on linux
 - `pipx run`: Verify whether the script name provided is a file before running it
 
 ## 1.4.1

src/pipx/util.py

@@ -174,7 +174,7 @@ def run_subprocess(
     # See https://github.com/pypa/pipx/issues/1164
     # Conversely, if the binary is a symlink, then we should NOT use the real path, as Python expects to receive the
     # symlink in argv[0] so that it can locate the venv.
-    if not os.path.islink(cmd_str_list[0]):
+    if not os.path.islink(cmd_str_list[0]) and WINDOWS:
         cmd_str_list[0] = os.path.realpath(cmd_str_list[0])
     completed_process = subprocess.run(
         cmd_str_list,

tests/test_util.py

@@ -0,0 +1,26 @@
+import sys
+
+import pytest  # type: ignore
+
+from pipx import util
+from pipx.util import run_subprocess
+
+
+@pytest.mark.skipif(sys.platform.startswith("win"), reason="Path resolution skip if not on windows")
+def test_executable_path_resolution_unix():
+    cmd = ["python99.99", "-c", "import sys;"]
+    try:
+        run_subprocess(cmd)
+    except FileNotFoundError as e:
+        assert "No such file or directory: 'python99.99'" in str(e)
+
+
+@pytest.mark.skipif(sys.platform.startswith("win"), reason="Path resolution skip if not on windows")
+def test_executable_path_resolution_fails_on_unix_if_not_skipped(monkeypatch: pytest.MonkeyPatch):
+    cmd = ["python99.99", "-c", "import sys;"]
+    monkeypatch.setattr(util, "WINDOWS", True)
+    monkeypatch.chdir("./tests")
+    try:
+        run_subprocess(cmd)
+    except FileNotFoundError as e:
+        assert "tests/python99.99'" in str(e)