Migrate to pyproject.toml and towncrier fragments

.github/bump_version.py

@@ -0,0 +1,79 @@
+"""Infer semver bump from towncrier fragment types and update version."""
+
+import re
+import sys
+from pathlib import Path
+
+
+def get_current_version(pyproject_path: Path) -> str:
+    text = pyproject_path.read_text()
+    match = re.search(r'^version\s*=\s*"(\d+\.\d+\.\d+)"', text, re.MULTILINE)
+    if not match:
+        print(
+            "Could not find version in pyproject.toml",
+            file=sys.stderr,
+        )
+        sys.exit(1)
+    return match.group(1)
+
+
+def infer_bump(changelog_dir: Path) -> str:
+    fragments = [
+        f
+        for f in changelog_dir.iterdir()
+        if f.is_file() and f.name != ".gitkeep"
+    ]
+    if not fragments:
+        print("No changelog fragments found", file=sys.stderr)
+        sys.exit(1)
+
+    categories = {f.suffix.lstrip(".") for f in fragments}
+    for f in fragments:
+        parts = f.stem.split(".")
+        if len(parts) >= 2:
+            categories.add(parts[-1])
+
+    if "breaking" in categories:
+        return "major"
+    if "added" in categories or "removed" in categories:
+        return "minor"
+    return "patch"
+
+
+def bump_version(version: str, bump: str) -> str:
+    major, minor, patch = (int(x) for x in version.split("."))
+    if bump == "major":
+        return f"{major + 1}.0.0"
+    elif bump == "minor":
+        return f"{major}.{minor + 1}.0"
+    else:
+        return f"{major}.{minor}.{patch + 1}"
+
+
+def update_file(path: Path, old_version: str, new_version: str):
+    text = path.read_text()
+    updated = text.replace(
+        f'version = "{old_version}"',
+        f'version = "{new_version}"',
+    )
+    if updated != text:
+        path.write_text(updated)
+        print(f"  Updated {path}")
+
+
+def main():
+    root = Path(__file__).resolve().parent.parent
+    pyproject = root / "pyproject.toml"
+    changelog_dir = root / "changelog.d"
+
+    current = get_current_version(pyproject)
+    bump = infer_bump(changelog_dir)
+    new = bump_version(current, bump)
+
+    print(f"Version: {current} -> {new} ({bump})")
+
+    update_file(pyproject, current, new)
+
+
+if __name__ == "__main__":
+    main()

.github/workflows/pr.yml

@@ -18,26 +18,20 @@ jobs:
         uses: psf/black@stable
         with:
           options: ". -l 79 --check"
-  check-version:
-    name: Check version
+  check-changelog:
+    name: Check changelog fragment
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout repo
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-          repository: ${{ github.event.pull_request.head.repo.full_name }}
-          ref: ${{ github.event.pull_request.head.ref }}
-      - name: Set up Python
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.11"
-      - name: Build changelog
-        run: pip install yaml-changelog && make changelog
-      - name: Preview changelog update
-        run: ".github/get-changelog-diff.sh"
-      - name: Check version number has been properly updated
-        run: ".github/is-version-number-acceptable.sh"
+      - uses: actions/checkout@v4
+      - name: Check for changelog fragment
+        run: |
+          FRAGMENTS=$(find changelog.d -type f ! -name '.gitkeep' | wc -l)
+          if [ "$FRAGMENTS" -eq 0 ]; then
+            echo "::error::No changelog fragment found in changelog.d/"
+            echo "Add one with: echo 'Description.' > changelog.d/\$(git branch --show-current).<type>.md"
+            echo "Types: added, changed, fixed, removed, breaking"
+            exit 1
+          fi
   test_container_builds:
     name: Docker
     runs-on: ubuntu-latest

.github/workflows/push.yml

@@ -54,16 +54,16 @@ jobs:
     steps:
       - name: Checkout repo
         uses: actions/checkout@v4
-        with:
-          repository: ${{ github.event.pull_request.head.repo.full_name }}
-          ref: ${{ github.event.pull_request.head.ref }}
-          token: ${{ secrets.POLICYENGINE_GITHUB }}
+        with:          token: ${{ secrets.POLICYENGINE_GITHUB }}
       - name: Setup Python
         uses: actions/setup-python@v5
         with:
           python-version: "3.11"
       - name: Build changelog
-        run: pip install yaml-changelog && make changelog
+        run: |
+          pip install towncrier
+          python .github/bump_version.py
+          towncrier build --yes --version $(python -c "import re; print(re.search(r'version = \"(.+?)\"', open('pyproject.toml').read()).group(1))")
       - name: Preview changelog update
         run: ".github/get-changelog-diff.sh"
       - name: Update changelog

Makefile

@@ -29,8 +29,5 @@ deploy:
 	rm .dbpw
 
 changelog:
-	build-changelog changelog.yaml --output changelog.yaml --update-last-date --start-from 0.1.0 --append-file changelog_entry.yaml
-	build-changelog changelog.yaml --org PolicyEngine --repo policyengine-api --output CHANGELOG.md --template .github/changelog_template.md
-	bump-version changelog.yaml setup.py policyengine_api/constants.py
-	rm changelog_entry.yaml || true
-	touch changelog_entry.yaml 
+	python .github/bump_version.py
+	towncrier build --yes --version $$(python -c "import re; print(re.search(r'version = \"(.+?)\"', open('pyproject.toml').read()).group(1))")

changelog.d/migrate-to-towncrier.changed.md

@@ -0,0 +1 @@
+Migrated from changelog_entry.yaml to towncrier fragments to eliminate merge conflicts.