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#!/usr/bin/env python3
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
import os
import platform
import sys
import subprocess
import traceback
from textwrap import dedent, fill
MIN_PYTHON_VERSION = (3, 8)
MAX_PYTHON_VERSION_TO_CONSIDER = (3, 11)
def load_mach(dir_path, mach_path, args):
# Defer import of "importlib.util" until after Python version check has happened
# so that Python 2 usages fail gracefully.
import importlib.util
spec = importlib.util.spec_from_file_location("mach_initialize", mach_path)
mach_initialize = importlib.util.module_from_spec(spec)
spec.loader.exec_module(mach_initialize)
return mach_initialize.initialize(dir_path, args)
def check_and_get_mach(dir_path, args):
initialize_paths = (
# Run Thunderbird's mach_initialize.py if it exists
"comm/build/mach_initialize.py",
"build/mach_initialize.py",
# test package initialize
"tools/mach_initialize.py",
)
for initialize_path in initialize_paths:
mach_path = os.path.join(dir_path, initialize_path)
if os.path.isfile(mach_path):
return load_mach(dir_path, mach_path, args)
return None
def find_alternate_python3_executables():
for i in range(MIN_PYTHON_VERSION[1], MAX_PYTHON_VERSION_TO_CONSIDER[1] + 1):
potential_python_binary = f"python3.{i}"
if os.name == "nt":
potential_python_binary += ".exe"
try:
out = subprocess.run(
[potential_python_binary, "--version"],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
encoding="UTF-8",
)
binary_minor_version = int(out.stdout[9:11].strip("."))
if binary_minor_version >= MIN_PYTHON_VERSION[1]:
yield potential_python_binary
except Exception:
pass
def try_alternate_python3_executables(args):
for potential_python_binary in find_alternate_python3_executables():
try:
print(
f"We found '{potential_python_binary}' and will attempt to re-run Mach with it."
)
os.execvp(
potential_python_binary, [potential_python_binary] + ["mach"] + args
)
except Exception:
# We don't really care what goes wrong, just don't let it bubble up
# If we can't successfully launch with a different python3 binary
# we will just print the normal help messages.
pass
def main(args):
# Ensure we are running Python 3.8+. We run this check as soon as
# possible to avoid a cryptic import/usage error.
if sys.version_info < MIN_PYTHON_VERSION:
print(
f"Python {MIN_PYTHON_VERSION[0]}.{MIN_PYTHON_VERSION[1]}+ is required to run mach."
)
print("You are running Mach with Python {0}".format(platform.python_version()))
try_alternate_python3_executables(args)
if sys.platform.startswith("linux"):
print(
dedent(
"""
for guidance on how to install Python on your system.
"""
).strip()
)
elif sys.platform.startswith("darwin"):
print(
dedent(
"""
for guidance on how to prepare your system to build Firefox. Perhaps
you need to update Xcode, or install Python using brew?
"""
).strip()
)
elif "MOZILLABUILD" in os.environ and os.environ.get("TERM"):
print(
dedent(
"""
Python is provided by MozillaBuild; ensure your MozillaBuild installation is
up to date. See https://firefox-source-docs.mozilla.org/setup/windows_build.html#install-mozillabuild
for details.
"""
).strip()
)
elif sys.platform.startswith("win"):
print(
dedent(
"""
You probably want to be interacting with Mach from within MozillaBuild, see
If you are deliberately using Mach from outside MozillaBuild, then see
for guidance on installing native Python on your system.
"""
).strip()
)
else:
print(
dedent(
"""
We do not have specific instructions for your platform on how to
helpful, if your system package manager does not provide a way to
install a recent enough Python 3.
"""
).strip()
)
sys.exit(1)
# XCode python sets __PYVENV_LAUNCHER__, which overrides the executable
# used when a python subprocess is created. This is an issue when we want
# to run using our virtualenv python executables.
# In future Python relases, __PYVENV_LAUNCHER__ will be cleared before
# application code (mach) is started.
os.environ.pop("__PYVENV_LAUNCHER__", None)
try:
mach = check_and_get_mach(os.path.dirname(os.path.realpath(__file__)), args)
if not mach:
print("Could not run mach: No mach source directory found.")
sys.exit(1)
sys.exit(mach.run(args))
except (KeyboardInterrupt, SystemExit):
raise
except Exception as e:
if sys.version_info >= (
MAX_PYTHON_VERSION_TO_CONSIDER[0],
MAX_PYTHON_VERSION_TO_CONSIDER[1] + 1,
):
traceback.print_exc()
print()
print("---")
print()
print(
fill(
dedent(
f"""\
Note that you are running Mach with Python
{platform.python_version()}, which is higher than the highest
known working version of Python for Mach. Consider running Mach
with Python {MAX_PYTHON_VERSION_TO_CONSIDER[0]}.{MAX_PYTHON_VERSION_TO_CONSIDER[1]}
or lower."""
)
)
)
try:
alternative = next(find_alternate_python3_executables())
print()
print("Running the following command may solve your issue:")
print()
print(f" {alternative} {sys.argv[0]} {' '.join(args)}")
print()
except StopIteration:
pass
sys.exit(1)
else:
raise
if __name__ == "__main__":
main(sys.argv[1:])