Support creating pyz files for different platforms

setup.py

@@ -16,6 +16,7 @@
     'click==6.7',
     'pip>=9.0.1',
     'importlib_resources>=0.4',
+    'wheel',
 ]
 
 # The following template and classmethod are copied from

src/shiv/cli.py

@@ -3,13 +3,17 @@
 import sys
 import uuid
 
+from collections import defaultdict
 from configparser import ConfigParser
 from pathlib import Path
+from shutil import rmtree
 from tempfile import TemporaryDirectory
 from typing import Optional, List
 
 import click
 
+from wheel.install import WheelFile
+
 from . import pip
 from . import builder
 from . import bootstrap
@@ -55,11 +59,9 @@ def validate_interpreter(interpreter_path: Optional[str] = None) -> Path:
         interpreter_path
     )
 
-    if real_path.exists():
-        return real_path
-
-    else:
-        sys.exit(INVALID_PYTHON.format(path=real_path))
+    if not real_path.exists():
+        print(INVALID_PYTHON.format(path=real_path))
+    return real_path
 
 
 def copy_bootstrap(bootstrap_target: Path) -> None:
@@ -73,6 +75,28 @@ def copy_bootstrap(bootstrap_target: Path) -> None:
                 shutil.copyfile(f.absolute(), bootstrap_target / f.name)
 
 
+def install_wheels(wheel_dir: Path, site_packages: Path) -> None:
+    """Install wheels from wheel_dir into site_packages"""
+    to_install = [WheelFile(req) for req in wheel_dir.glob('*.whl')]
+
+    # We now have a list of wheels to install
+    print("Installing:")
+
+    # Ensure we always put stuff in site-packages no matter what
+    overrides = {
+        'purelib': str(site_packages),
+        'platlib': str(site_packages),
+        'headers': str(Path(site_packages, '..', 'headers')),
+        'scripts': str(Path(site_packages, '..', 'scripts')),
+        'data': str(Path(site_packages, '..', 'data')),
+    }
+    for wf in to_install:
+        print("    {}".format(wf.filename))
+        wf.install(force=True, overrides=overrides)
+        wf.zipfile.close()
+
+
+
 @click.command(
     context_settings=dict(
         help_option_names=["-h", "--help", "--halp"], ignore_unknown_options=True
@@ -128,15 +152,24 @@ def main(
     interpreter = validate_interpreter(python)
 
     with TemporaryDirectory() as working_path:
+        wheel_dir = Path(working_path, "wheelhouse")
+        wheel_dir.mkdir(parents=True, exist_ok=True)
+
         site_packages = Path(working_path, "site-packages")
         site_packages.mkdir(parents=True, exist_ok=True)
 
-        # install deps into staged site-packages
-        pip.install(
-            python or sys.executable,
-            ["--target", site_packages.as_posix()] + list(pip_args),
+        # download wheels into wheel_dir
+        pip.download(
+            sys.executable,
+            ["--dest", str(wheel_dir)] + list(pip_args),
         )
 
+        # install deps into staged site-packages
+        install_wheels(wheel_dir, site_packages)
+
+        # remove wheels
+        rmtree(str(wheel_dir))
+
         # if entry_point is a console script, get the callable
         if entry_point is None and console_script is not None:
             try:

src/shiv/constants.py

@@ -5,16 +5,13 @@
 DISALLOWED_PIP_ARGS = "\nYou supplied a disallowed pip argument! '{arg}'\n\n{reason}\n"
 NO_PIP_ARGS = "\nYou must supply PIP ARGS!\n"
 NO_OUTFILE = "\nYou must provide an output file option! (--output-file/-o)\n"
-INVALID_PYTHON = "\nInvalid python interpreter! {path} does not exist!\n"
+INVALID_PYTHON = "\nInvalid python interpreter! {path} does not exist!\nThe output file will only work on a machine where this path exists.\n"
 NO_ENTRY_POINT = "\nNo entry point '{entry_point}' found in the console_scripts!\n"
-PIP_INSTALL_ERROR = "\nPip install failed!\n"
+PIP_DOWNLOAD_ERROR = "\nPip download failed!\n"
+
 
 # pip
-PIP_INSTALL_ERROR = "\nPip install failed!\n"
 PIP_REQUIRE_VIRTUALENV = "PIP_REQUIRE_VIRTUALENV"
 BLACKLISTED_ARGS: Dict[Tuple[str, ...], str] = {
-    ("-t", "--target"): "Shiv already supplies a target internally, so overriding is not allowed.",
-    ("--editable", ): "Editable installs don't actually install via pip (they are just linked), so they are not allowed.",
-    ("-d", "--download"): "Shiv needs to actually perform an install, not merely a download.",
-    ("--user", "--root", "--prefix"): "Which conflicts with Shiv's internal use of '--target'.",
+    ("-d", "--dest"): "Shiv already supplies a destination internally, so overriding is not allowed.",
 }

src/shiv/pip.py

@@ -5,7 +5,7 @@
 
 from typing import Generator, List
 
-from .constants import PIP_REQUIRE_VIRTUALENV, PIP_INSTALL_ERROR
+from .constants import PIP_REQUIRE_VIRTUALENV, PIP_DOWNLOAD_ERROR
 
 
 @contextlib.contextmanager
@@ -25,25 +25,22 @@ def clean_pip_env() -> Generator[None, None, None]:
             os.environ[PIP_REQUIRE_VIRTUALENV] = require_venv
 
 
-def install(interpreter_path: str, args: List[str]) -> None:
-    """`pip install` as a function.
+def download(interpreter_path: str, args: List[str]) -> None:
+    """`pip download` as a function.
 
     Accepts a list of pip arguments.
 
     .. code-block:: py
 
-        >>> install('/usr/local/bin/python3', ['numpy', '--target', 'site-packages'])
+        >>> download('/usr/local/bin/python3', ['numpy', '--dest', 'site-packages'])
         Collecting numpy
         Downloading numpy-1.13.3-cp35-cp35m-manylinux1_x86_64.whl (16.9MB)
             100% || 16.9MB 53kB/s
-        Installing collected packages: numpy
-        Successfully installed numpy-1.13.3
-
     """
     with clean_pip_env():
 
         process = subprocess.Popen(
-            [interpreter_path, "-m", "pip", "--disable-pip-version-check", "install"] + args,
+            [interpreter_path, "-m", "pip", "--disable-pip-version-check", "download"] + args,
             stdout=subprocess.PIPE,
             stderr=subprocess.STDOUT,
         )
@@ -53,4 +50,4 @@ def install(interpreter_path: str, args: List[str]) -> None:
                 print(output.decode().rstrip())
 
         if process.wait() > 0:
-            sys.exit(PIP_INSTALL_ERROR)
+            sys.exit(PIP_DOWNLOAD_ERROR)