tools: add release script

tools/release

@@ -0,0 +1,165 @@
+#!/usr/bin/env python3
+import argparse
+import re
+import sys
+from datetime import datetime
+from pathlib import Path
+from subprocess import check_output, run
+
+from shared.common import REPO_DIR
+from shared.versioning import get_branch_version
+
+HEADER = "## [Unreleased](https://github.com/LostArtefacts/TR2X/compare/stable...develop) - ××××-××-××"
+CHANGELOG_PATH = REPO_DIR / "CHANGELOG.md"
+
+
+def update_changelog(
+    changelog: str, old_version: str, new_version: str
+) -> str:
+    if f"[{new_version}]" in changelog:
+        return changelog
+    changelog = re.sub("Unreleased", new_version, changelog, count=1)
+    changelog = re.sub("stable", old_version, changelog, count=1)
+    changelog = re.sub("develop", new_version, changelog, count=1)
+    changelog = re.sub(
+        "××××-××-××", datetime.now().strftime("%Y-%m-%d"), changelog
+    )
+    changelog = HEADER + "\n\n" + changelog
+    return changelog
+
+
+class Git:
+    def checkout_branch(self, branch_name: str) -> None:
+        if check_output(["git", "diff", "--cached", "--name-only"]):
+            raise RuntimeError("Staged files")
+        check_output(["git", "checkout", branch_name])
+
+    def reset(self, target: str, hard: bool = False) -> None:
+        check_output(
+            ["git", "reset", "develop", *(["--hard"] if hard else [])]
+        )
+
+    def delete_tag(self, tag_name: str) -> None:
+        run(["git", "tag", "-d", tag_name])
+
+    def create_tag(self, tag_name: str) -> None:
+        check_output(["git", "tag", tag_name])
+
+    def add(self, target: str) -> None:
+        check_output(["git", "add", target])
+
+    def commit(self, message: str) -> None:
+        check_output(["git", "commit", "-m", message])
+
+    def push(
+        self, upstream: str, targets: list[str], force: bool = False
+    ) -> None:
+        check_output(
+            [
+                "git",
+                "push",
+                upstream,
+                *targets,
+                *(["--force-with-lease"] if force else []),
+            ]
+        )
+
+
+class BaseCommand:
+    name: str = NotImplemented
+    help: str = NotImplemented
+
+    def __init__(self, git: Git) -> None:
+        self.git = git
+
+    def decorate_parser(self, parser: argparse.ArgumentParser) -> None:
+        parser.add_argument("version")
+
+    def run(self, args: argparse.Namespace) -> None:
+        raise NotImplementedError("not implemented")
+
+
+class CommitCommand(BaseCommand):
+    name = "commit"
+    help = "Create and tag a commit with the release information"
+
+    def decorate_parser(self, parser: argparse.ArgumentParser) -> None:
+        super().decorate_parser(parser)
+        parser.add_argument(
+            "-d",
+            "--dry-run",
+            action='store_true',
+            help="only output the changelog to stdout, do not commit anything",
+        )
+
+    def run(self, args: argparse.Namespace) -> None:
+        self.git.checkout_branch("develop")
+        old_version = get_branch_version("origin/stable")
+        new_version = args.version
+
+        old_changelog = CHANGELOG_PATH.read_text()
+        new_changelog = update_changelog(
+            old_changelog, old_version, args.version
+        )
+        if old_changelog == new_changelog:
+            return
+
+        if args.dry_run:
+            print(new_changelog)
+            return
+
+        CHANGELOG_PATH.write_text(new_changelog)
+        self.git.add(CHANGELOG_PATH)
+        self.git.commit(f"docs: release {args.version}")
+        self.git.delete_tag(args.version)
+        self.git.create_tag(args.version)
+
+
+class BranchCommand(BaseCommand):
+    name = "branch"
+    help = "Merge branch to the specified tag"
+
+    def run(self, args: argparse.Namespace) -> None:
+        self.git.checkout_branch("stable")
+        self.git.reset(args.version, hard=True)
+        self.git.checkout_branch("develop")
+
+
+class PushCommand(BaseCommand):
+    name = "push"
+    help = (
+        "Push the develop and stable branches, and the version tag to GitHub"
+    )
+
+    def run(self, args) -> None:
+        self.git.push(
+            "origin", ["develop", "stable", args.version], force=True
+        )
+
+
+def parse_args(commands: list[BaseCommand]) -> None:
+    parser = argparse.ArgumentParser(
+        description="Argument parser with subcommands"
+    )
+    subparsers = parser.add_subparsers(title="subcommands", dest="subcommand")
+    for command in commands:
+        subparser = subparsers.add_parser(command.name, help=command.help)
+        command.decorate_parser(subparser)
+        subparser.set_defaults(command=command)
+
+    result = parser.parse_args()
+    if not hasattr(result, "command"):
+        parser.error("missing command")
+    return result
+
+
+def main() -> None:
+    git = Git()
+    commands = [
+        command_cls(git) for command_cls in BaseCommand.__subclasses__()
+    ]
+    args = parse_args(commands)
+    args.command.run(args)
+
+
+main()