Move default cache root from ~/.shiv to ~/.cache/shiv

README.md

@@ -102,7 +102,7 @@ sphinx-build docs build/html
 Zipapps created with shiv are not guaranteed to be cross-compatible with other architectures. For example, a `pyz`
  file built on a Mac may only work on other Macs, likewise for RHEL, etc. This usually only applies to zipapps that have C extensions in their dependencies. If all your dependencies are pure python, then chances are the `pyz` _will_ work on other platforms. Just something to be aware of.
 
-Zipapps created with shiv *will* extract themselves into `~/.shiv`, unless overridden via
+Zipapps created with shiv *will* extract themselves into `~/.cache/shiv` (platform dependent), unless overridden via
 `SHIV_ROOT`. If you create many utilities with shiv, you may want to occasionally clean this
 directory.
 

docs/index.rst

@@ -93,7 +93,7 @@ Bootstrapping
 ^^^^^^^^^^^^^
 
 As mentioned above, when you run an executable created with ``shiv``, a special bootstrap function is called.
-This function unpacks the dependencies into a uniquely named subdirectory of ``~/.shiv`` and then runs your entry point
+This function unpacks the dependencies into a uniquely named subdirectory of ``~/.cache/shiv`` (platform dependent) and then runs your entry point
 (or interactive interpreter) with those dependencies added to your interpreter's search path (``sys.path``).
 
 To improve performance, once the dependencies have been extracted to disk, any further invocations will re-use the 'cached'
@@ -126,7 +126,7 @@ If the preamble file is written in Python (e.g. ends in ``.py``) then shiv will
 * ``env``: an instance of the `Environment <api:bootstrap.environment.Environment>`_ object.
 * ``site_packages``: a :py:class:`pathlib.Path` of the directory where the current PYZ's site_packages were extracted to during bootstrap.
 
-For an example, a preamble file that cleans up prior extracted ``~/.shiv`` directories might look like:
+For an example, a preamble file that cleans up prior extracted ``~/.cache/shiv`` directories might look like:
 
 .. code-block:: py
 
@@ -225,7 +225,7 @@ you can specify to influence a zipapp created with shiv at run time.
 SHIV_ROOT
 ^^^^^^^^^
 
-This should be populated with a full path, it overrides ``~/.shiv`` as the default base dir for shiv's extraction cache.
+This should be populated with a full path, it overrides ``~/.cache/shiv`` (platform dependent) as the default base dir for shiv's extraction cache.
 
 This is useful if you want to collect the contents of a zipapp to inspect them, or if you want to make a quick edit to
 a source file, but don't want to taint the extraction cache.

src/shiv/bootstrap/__init__.py

@@ -87,8 +87,33 @@ def import_string(import_name):
         raise ImportError(e)
 
 
+def get_default_cache_root():
+    """Returns the platform dependent default cache directory."""
+
+    # Previous versions used "~/.shiv". If it exists, continue using it.
+    legacy_root = Path("~/.shiv").expanduser()
+    if legacy_root.is_dir():
+        return legacy_root
+
+    # Loosely based on https://github.com/platformdirs/platformdirs
+
+    if sys.platform == "win32":
+        local_app_data = os.environ.get("LOCALAPPDATA", "")
+        if local_app_data.strip():
+            return Path(os.path.normpath(local_app_data)) / "shiv" / "cache"
+
+    if sys.platform == "darwin":
+        return Path("~/Library/Caches/shiv").expanduser()
+
+    xdg_cache_home = os.environ.get("XDG_CACHE_HOME", "")
+    if xdg_cache_home.strip():
+        return Path(os.path.normpath(xdg_cache_home)) / "shiv"
+
+    return Path("~/.cache/shiv").expanduser()
+
+
 def cache_path(archive, root_dir, build_id):
-    """Returns a ~/.shiv cache directory for unzipping site-packages during bootstrap.
+    """Returns a cache directory for unzipping site-packages during bootstrap.
 
     :param ZipFile archive: The zipfile object we are bootstrapping from.
     :param str root_dir: Optional, either a path or environment variable pointing to a SHIV_ROOT.
@@ -102,7 +127,7 @@ def cache_path(archive, root_dir, build_id):
 
         root_dir = Path(root_dir).expanduser()
 
-    root = root_dir or Path("~/.shiv").expanduser()
+    root = root_dir or get_default_cache_root()
     name = Path(archive.filename).resolve().name
     return root / f"{name}_{build_id}"
 
@@ -120,7 +145,7 @@ def extract_site_packages(archive, target_path, compile_pyc=False, compile_worke
     target_path_tmp = Path(parent, target_path.name + ".tmp")
     lock = Path(parent, f".{target_path.name}_lock")
 
-    # If this is the first time that a pyz is being extracted, we'll need to create the ~/.shiv dir
+    # If this is the first time that a pyz is being extracted, we'll need to create the cache root dir
     if not parent.exists():
         parent.mkdir(parents=True, exist_ok=True)
 

src/shiv/cli.py

@@ -143,7 +143,7 @@ def copytree(src: Path, dst: Path) -> None:
     is_flag=True,
     help=(
         "If specified, this modifies the runtime of the zipapp to raise "
-        "a RuntimeException if the source files (in ~/.shiv or SHIV_ROOT) have been modified. "
+        "a RuntimeException if the source files (in ~/.cache/shiv or SHIV_ROOT) have been modified. "
         """It's recommended to use Python's "--check-hash-based-pycs always" option with this feature."""
     ),
 )
@@ -155,7 +155,11 @@ def copytree(src: Path, dst: Path) -> None:
         "but before invoking your entry point."
     ),
 )
-@click.option("--root", type=click.Path(), help="Override the 'root' path (default is ~/.shiv).")
+@click.option(
+    "--root",
+    type=click.Path(),
+    help="Override the 'root' path (default is platform dependent, e.g. ~/.cache/shiv).",
+)
 @click.argument("pip_args", nargs=-1, type=click.UNPROCESSED)
 def main(
     output_file: str,