Build script for third-party distributions (#2545)

Part of #2491

Author: srittau

third_party/build/METADATA.tmpl

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+Metadata-Version: 2.1
+Name: $PACKAGE$-ts
+Version: $VERSION$
+Summary: Type stubs for $PACKAGE$
+Description-Content-Type: text/markdown
+Keywords: typehints typing type-hints typeshed
+Home-page: https://github.com/python/typeshed
+Classifier: Intended Audience :: Developers
+Classifier: License :: OSI Approved :: Apache Software License
+Classifier: Programming Language :: Python
+$TROVE_PY$
+Classifier: Topic :: Software Development :: Libraries :: Python Modules
+Requires-Python: $PY_REQUIRES$
+
+# Type stubs for $PACKAGE$
+
+These type stubs are part of the [typeshed project](https://github.com/python/typeshed).
+

third_party/build/WHEEL.tmpl

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+Wheel-Version: 1.0
+Generator: typeshed
+Root-Is-Purelib: true

third_party/build/build-dist.py

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+#!/usr/bin/env python3
+
+# Build a stubs-only distribution for a third-party package.
+#
+# Usage: python3.7 build-dist.py <PACKAGE>
+#
+# The resulting wheel will be saved in third-party/build/dist.
+
+import datetime
+import os
+import re
+import shutil
+import subprocess
+import sys
+from dataclasses import dataclass
+from pathlib import Path
+from typing import List
+
+DIST_SUFFIX = "-ts"
+MIN_PYTHON3_VERSION = (3, 4)
+MAX_PYTHON3_VERSION = (3, 7)
+EXCLUDED_PYTHON_VERSIONS = [(3, i) for i in range(MIN_PYTHON3_VERSION[1])]
+TROVE_PREFIX = "Classifier: Programming Language :: Python :: "
+
+pkg_version = "0." + datetime.datetime.now().strftime("%Y%m%d.%H%M")
+py_version_re = re.compile(r"^(2and3|\d+(\.\d+)?)$")
+
+base_dir = Path(__file__).parent
+root_dir = base_dir.parent.parent
+build_dir = base_dir / "build"
+dist_dir = base_dir / "dist"
+
+@dataclass
+class PackageInfo:
+    path: Path
+    name: str
+    py_version: str
+    is_module: bool
+
+    @property
+    def stub_name(self) -> str:
+        return f"{self.name}-stubs"
+
+
+def py_version_to_wheel_tags(version: str) -> List[str]:
+    if version == "2and3":
+        return ["py2-none-any", "py3-none-any"]
+    else:
+        return [f"py{version}-none-any"]
+
+
+def py_version_to_requires(version: str) -> str:
+    if version == "2":
+        return ">= 2.7, < 3"
+    elif version == "2and3":
+        formatted = [f"!= {ma}.{mi}.*" for ma, mi in EXCLUDED_PYTHON_VERSIONS]
+        return ">= 2.7, " + ", ".join(formatted)
+    elif version == "3":
+        return f">= {MIN_PYTHON3_VERSION[0]}.{MIN_PYTHON3_VERSION[1]}"
+    else:
+        return ">= " + version
+
+
+def py_version_to_trove(version: str) -> List[str]:
+    py2_versions = ["2", "2.7"]
+    if version == "2":
+        versions = py2_versions + ["2 :: Only"]
+    elif version == "2and3":
+        versions = py2_versions + py3_versions()
+    elif version == "3":
+        versions = py3_versions() + ["3 :: Only"]
+    else:
+        versions = py3_versions(int(version[2:])) + ["3 :: Only"]
+    return [TROVE_PREFIX + v for v in versions]
+
+def py3_versions(min_v: int = MIN_PYTHON3_VERSION[1]) -> List[str]:
+    assert min_v <= MAX_PYTHON3_VERSION[1]
+    r = range(min_v, MAX_PYTHON3_VERSION[1] + 1)
+    return ["3"] + [f"3.{i}" for i in r]
+
+
+def parse_args() -> str:
+    if len(sys.argv) != 2:
+        print(f"Usage: {sys.argv[0]} PACKAGE", file=sys.stderr)
+        sys.exit(1)
+    return sys.argv[1]
+
+
+def find_package(name: str) -> PackageInfo:
+    for dir_ in base_dir.parent.iterdir():
+        if not py_version_re.match(dir_.name):
+            continue
+        pkg_path = dir_ / name
+        mod_path = dir_ / f"{name}.pyi"
+        if pkg_path.is_dir():
+            return PackageInfo(pkg_path, name, dir_.name, is_module=False)
+        elif mod_path.is_file():
+            return PackageInfo(mod_path, name, dir_.name, is_module=True)
+    print(f"Stubs for package '{name}' not found", file=sys.stderr)
+    sys.exit(1)
+
+
+def build_distribution(package: PackageInfo) -> None:
+    prepare_build_dir(package)
+    pack_wheel(package)
+
+
+def prepare_build_dir(package: PackageInfo) -> None:
+    shutil.rmtree(build_dir, ignore_errors=True)
+    copy_package(package)
+    pkg = (package.name + DIST_SUFFIX).replace("-", "_")
+    dist_info_dir = build_dir / f"{pkg}-{pkg_version}.dist-info"
+    os.mkdir(dist_info_dir)
+    shutil.copy(root_dir / "LICENSE", dist_info_dir)
+    create_wheel_file(package, base_dir / "WHEEL.tmpl",
+                      dist_info_dir / "WHEEL")
+    create_metadata(package, base_dir / "METADATA.tmpl",
+                    dist_info_dir / "METADATA")
+
+
+def copy_package(package: PackageInfo) -> None:
+    dest_dir = build_dir / package.stub_name
+    if package.is_module:
+        os.makedirs(dest_dir)
+        shutil.copyfile(package.path, dest_dir / "__init__.pyi")
+    else:
+        shutil.copytree(package.path, dest_dir)
+
+
+def create_wheel_file(package: PackageInfo, src: Path, dest: Path) -> None:
+    with open(dest, "w") as f:
+        with open(src, "r") as src_f:
+            for line in src_f:
+                f.write(line)
+        for tag in py_version_to_wheel_tags(package.py_version):
+            f.write(f"Tag: {tag}\n")
+
+
+def create_metadata(package: PackageInfo, src: Path, dest: Path) -> None:
+    py_requires = py_version_to_requires(package.py_version)
+    with open(dest, "w") as f:
+        with open(src, "r") as src_f:
+            for line in src_f:
+                if line.startswith("$TROVE_PY$"):
+                    for trove in py_version_to_trove(package.py_version):
+                        f.write(f"Classifier: {trove}\n")
+                else:
+                    line = line.replace("$PACKAGE$", package.name)
+                    line = line.replace("$VERSION$", pkg_version)
+                    line = line.replace("$PY_REQUIRES$", py_requires)
+                    f.write(line)
+
+
+def pack_wheel(package: PackageInfo) -> None:
+    os.makedirs(dist_dir, exist_ok=True)
+    subprocess.run(["wheel", "pack", str(build_dir),
+                    "--dest-dir", str(dist_dir)])
+
+
+def main() -> None:
+    package_name = parse_args()
+    package = find_package(package_name)
+    build_distribution(package)
+
+
+if __name__ == "__main__":
+    main()