ci: Setup release-plz and related files (#765)

- Setups automatic changelog generation on merges to `main`
- Updates the README with the appropriate links (assuming the crate is
already released)

.github/workflows/release-plz.yml

@@ -0,0 +1,28 @@
+name: Release-plz
+
+permissions:
+  pull-requests: write
+  contents: write
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  release-plz:
+    name: Release-plz
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+      - name: Run release-plz
+        uses: MarcoIeni/[email protected]
+        with:
+          command: release-pr
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

README.md

@@ -2,6 +2,7 @@ quantinuum-hugr
 ===============
 
 [![build_status][]](https://github.com/CQCL/hugr/actions)
+[![crates][]](https://crates.io/crates/quantinuum-hugr)
 [![msrv][]](https://github.com/CQCL/hugr)
 [![codecov][]](https://codecov.io/gh/CQCL/hugr)
 
@@ -16,15 +17,21 @@ The HUGR specification is [here](specification/hugr.md).
 
 ## Usage
 
-Add this to your `Cargo.toml`:
+Add the dependency to your project:
 
-```toml
-[dependencies]
-quantinuum-hugr = "0.1"
+```bash
+cargo add quantinuum-hugr
 ```
 
 The library crate is called `hugr`.
 
+Please read the [API documentation here][].
+
+## Recent Changes
+
+See [CHANGELOG][] for a list of changes. The minimum supported rust
+version will only change on major releases.
+
 ## Development
 
 See [DEVELOPMENT.md](DEVELOPMENT.md) for instructions on setting up the development environment.
@@ -33,7 +40,9 @@ See [DEVELOPMENT.md](DEVELOPMENT.md) for instructions on setting up the developm
 
 This project is licensed under Apache License, Version 2.0 ([LICENSE][] or http://www.apache.org/licenses/LICENSE-2.0).
 
+  [API documentation here]: https://docs.rs/quantinuum-hugr/
   [build_status]: https://github.com/CQCL/hugr/workflows/Continuous%20integration/badge.svg?branch=main
   [msrv]: https://img.shields.io/badge/rust-1.75.0%2B-blue.svg
   [codecov]: https://img.shields.io/codecov/c/gh/CQCL/hugr?logo=codecov
   [LICENSE]: LICENCE
+  [CHANGELOG]: CHANGELOG.md

cliff.toml

@@ -0,0 +1,73 @@
+# git-cliff ~ default configuration file
+# https://git-cliff.org/docs/configuration
+#
+# Lines starting with "#" are comments.
+# Configuration options are organized into tables and keys.
+# See documentation for more information on available options.
+
+[changelog]
+# changelog header
+header = """
+# Changelog\n
+"""
+# template for the changelog body
+# https://tera.netlify.app/docs
+body = """
+{% if version %}\
+    ## {{ version }} ({{ timestamp | date(format="%Y-%m-%d") }})
+{% else %}\
+    ## Unreleased (XXXX-XX-XX)
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | upper_first }}
+    {% for commit in commits %}
+        - {% if commit.breaking %}[**breaking**] {% endif %}{{ commit.message | upper_first }}\
+    {% endfor %}
+{% endfor %}\n
+"""
+# remove the leading and trailing whitespace from the template
+trim = true
+# changelog footer
+footer = ""
+
+[git]
+# parse the commits based on https://www.conventionalcommits.org
+conventional_commits = true
+# filter out the commits that are not conventional
+filter_unconventional = true
+# process each line of a commit as an individual commit
+split_commits = false
+# regex for preprocessing the commit messages
+commit_preprocessors = [
+  { pattern = '\((\w+\s)?#([0-9]+)\)', replace = "([#${2}](https://github.com/CQCL/portgraph/issues/${2}))"}, # replace issue numbers
+]
+# regex for parsing and grouping commits
+commit_parsers = [
+  { message = "^feat", group = "Features" },
+  { message = "^fix", group = "Bug Fixes" },
+  { message = "^docs", group = "Documentation" },
+  { message = "^style", group = "Styling" },
+  { message = "^refactor", group = "Refactor" },
+  { message = "^perf", group = "Performance" },
+  { message = "^test", group = "Testing" },
+  { message = "^chore\\(release\\): prepare for", skip = true },
+  { message = "^chore", group = "Miscellaneous Tasks", skip = true },
+  { message = "^revert", group = "Reverted changes", skip = true },
+  { message = "^ci", group = "CI", skip = true },
+]
+# protect breaking changes from being skipped due to matching a skipping commit_parser
+protect_breaking_commits = true
+# filter out the commits that are not matched by commit parsers
+filter_commits = false
+# glob pattern for matching git tags
+tag_pattern = "v[0-9.]*"
+# regex for skipping tags
+skip_tags = "v0.1.0-beta.1"
+# regex for ignoring tags
+ignore_tags = ""
+# sort the tags topologically
+topo_order = false
+# sort the commits inside sections by oldest-first/newest-first
+sort_commits = "oldest"
+# limit the number of commits included in the changelog.
+# limit_commits = 42

release-plz.toml

@@ -0,0 +1,2 @@
+[workspace]
+changelog_config = "cliff.toml" # use a custom git-cliff configuration