Run commands using their real paths

Fixes pypa#1164

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## dev
 
+- Fix "No pyvenv.cfg file" error when using Microsoft Store Python (#1164)
 - Add `--quiet` and `--verbose` options for the `pipx` subcommands
 - [docs] Add Scoop installation instructions
 - Add ability to install multiple packages at once

src/pipx/util.py

@@ -171,6 +171,17 @@ def run_subprocess(
     logger.info(f"running {log_cmd_str}")
     # windows cannot take Path objects, only strings
     cmd_str_list = [str(c) for c in cmd]
+    # Make sure to call the binary using its real path. This matters especially
+    # on Windows when using the packaged app (Microsoft Store) version of
+    # Python, which uses path redirection for sandboxing. If the path to the
+    # executable is redirected, the executable can get confused as to which
+    # directory it's being run from, leading to problems.
+    # 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]):
+        cmd_str_list[0] = os.path.realpath(cmd_str_list[0])
     completed_process = subprocess.run(
         cmd_str_list,
         env=env,