Create a Docker image to generate the release change log

Dockerfile.changelog-rs

@@ -0,0 +1,12 @@
+FROM rust
+
+# Build the docker image (from this project's root directory):
+# docker build --file Dockerfile.changelog-rs --tag changelog-rs .
+#
+# Use this image to output a changelog (from this project's root directory):
+# docker run --rm --volume "$PWD:/worktree" changelog-rs v1.9.1 v1.10.0
+
+RUN cargo install changelog-rs
+WORKDIR /worktree
+
+ENTRYPOINT ["/usr/local/cargo/bin/changelog-rs", "/worktree"]

RELEASING.md

@@ -6,9 +6,11 @@
 # How to release a new git.gem
 
 Releasing a new version of the `git` gem requires these steps:
-  * [Prepare the release](#prepare-the-release)
-  * [Create a GitHub release](#create-a-github-release)
-  * [Build and release the gem](#build-and-release-the-gem)
+
+- [How to release a new git.gem](#how-to-release-a-new-gitgem)
+  - [Prepare the release](#prepare-the-release)
+  - [Create a GitHub release](#create-a-github-release)
+  - [Build and release the gem](#build-and-release-the-gem)
 
 These instructions use an example where the current release version is `1.5.0`
 and the new release version to be created is `1.6.0.pre1`.
@@ -18,45 +20,49 @@ and the new release version to be created is `1.6.0.pre1`.
 From a fork of ruby-git, create a PR containing changes to (1) bump the
 version number, (2) update the CHANGELOG.md, and (3) tag the release.
 
-  * Bump the version number in lib/git/version.rb following [Semantic Versioning](https://semver.org)
-    guidelines
-  * Add a link in CHANGELOG.md to the release tag which will be created later
-    in this guide
-  * Create a new tag using [git-extras](https://github.com/tj/git-extras/blob/master/Commands.md#git-release)
-    `git release` command
-    * For example: `git release v1.6.0.pre1`
-  * These should be the only changes in the PR
-  * An example of these changes for `v1.6.0.pre1` can be found in [PR #435](https://github.com/ruby-git/ruby-git/pull/435)
-  * Get the PR reviewed, approved and merged to master.
+- Bump the version number in lib/git/version.rb following [Semantic Versioning](https://semver.org)
+  guidelines
+- Add a link in CHANGELOG.md to the release tag which will be created later
+  in this guide
+- Create a new tag using [git-extras](https://github.com/tj/git-extras/blob/master/Commands.md#git-release)
+  `git release` command
+  - For example: `git release v1.6.0.pre1`
+- These should be the only changes in the PR
+- An example of these changes for `v1.6.0.pre1` can be found in [PR #435](https://github.com/ruby-git/ruby-git/pull/435)
+- Get the PR reviewed, approved and merged to master.
 
 ## Create a GitHub release
 
 On [the ruby-git releases page](https://github.com/ruby-git/ruby-git/releases),
 select `Draft a new release`
 
-  * Select the tag corresponding to the version being released `v1.6.0.pre1`
-  * The Target should be `master`
-  * For the release description, use the output of [changelog-rs](https://github.com/perlun/changelog-rs)
-    * Since the release has not been created yet, you will need to supply
-      `changeling-rs` with the current release tag and the tag the new release
-      is being created from
-    * For example: `changelog-rs . v1.5.0 v1.6.0.pre1`
-    * Copy the output, omitting the tag header `## v1.6.0.pre1` and paste into
-      the release description
-    * The release description can be edited later if needed
-  * Select the appropriate value for `This is a pre-release`
-    * Since `v1.6.0.pre1` is a pre-release, check `This is a pre-release`
+- Select the tag corresponding to the version being released `v1.6.0.pre1`
+- The Target should be `master`
+- For the release description, use the output of [changelog-rs](https://github.com/perlun/changelog-rs)
+  - A Docker image is provided in [Dockerfile.changelog-rs](https://github.com/ruby-git/ruby-git/blob/master/Dockerfile.changelog-rs)
+    so you don't have to install changelog-rs or the Rust tool chain. To build the
+    Docker image, run this command from this project's root directory:
+    - `docker build --file Dockerfile.changelog-rs --tag changelog-rs .`
+  - To run the changelog-rs command using this image, run the following command
+    from this project's root directory (replace the tag names appropriate for the
+    current release):
+    - `docker run --rm --volume "$PWD:/worktree" changelog-rs v1.5.0 v1.6.0.pre1`
+  - Copy the output, omitting the tag header `## v1.6.0.pre1` and paste into
+    the release description
+  - The release description can be edited later if needed
+- Select the appropriate value for `This is a pre-release`
+  - Since `v1.6.0.pre1` is a pre-release, check `This is a pre-release`
 
 ## Build and release the gem
 
 Clone [ruby-git/ruby-git](https://github.com/ruby-git/ruby-git) directly (not a
 fork) and ensure your local working copy is on the master branch
 
-  * Verify that you are not on a fork with the command `git remote -v`
-  * Verify that the version number is correct by running `rake -T` and inspecting
-    the output for the `release[remote]` task
+- Verify that you are not on a fork with the command `git remote -v`
+- Verify that the version number is correct by running `rake -T` and inspecting
+  the output for the `release[remote]` task
 
 Build the git gem and push it to rubygems.org with the command `rake release`
 
-  * Ensure that your `gem sources list` includes `https://rubygems.org` (in my
-    case, I usually have my work’s internal gem repository listed)
+- Ensure that your `gem sources list` includes `https://rubygems.org` (in my
+  case, I usually have my work’s internal gem repository listed)