fix(changelog): fix previous version links (#364)

* test: add more tests for previous links

* fix: fix wrong previous version

* test: fix wrong tag on test fixture

* test: add fixture for bump with keep a changelog links

* perf: avoid setting previous if already set

* style: remove unused comment

* refactor: change code style for readability

* fix: fix compilation failure

* docs: update with comments

* style: reformat code

---------

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

.github/actions/run-fixtures-test/action.yml

@@ -9,6 +9,10 @@ inputs:
     description: The git-cliff command to run
     required: false
     default: ""
+  date-format:
+    description: The date format to use
+    required: false
+    default: "%Y-%m-%d"
 
 runs:
   using: composite
@@ -40,7 +44,11 @@ runs:
 
     - name: Compare the output with the expected output
       working-directory: ${{ inputs.fixtures-dir }}
+      env:
+        IN_DATE_FORMAT: ${{ inputs.date-format }}
       run: |
         cat output.md
+        current_date=$(date +"$IN_DATE_FORMAT")
+        sed -i "s/<<DATE>>/$current_date/g" expected.md
         diff --strip-trailing-cr output.md expected.md
       shell: bash

.github/fixtures/test-keep-a-changelog-links-current-arg/cliff.toml

@@ -0,0 +1,77 @@
+[changelog]
+# changelog header
+header = """
+# Changelog\n
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).\n
+"""
+# template for the changelog body
+# https://keats.github.io/tera/docs/#introduction
+body = """
+{% if version %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/compare/{{ previous.version }}...{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% else %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/releases/tag/{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% endif %}\
+    {% endif %}\
+{% else %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [Unreleased](https://github.com/dummy/dummy/compare/{{ previous.version }}...HEAD)
+      {% else %}\
+          ## [Unreleased]
+      {% endif %}\
+    {% else %}\
+        ## [Unreleased]
+    {% endif %}\
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | upper_first }}
+    {% for commit in commits %}
+        - {{ commit.message | upper_first }}\
+    {% endfor %}
+{% endfor %}\n
+"""
+# remove the leading and trailing whitespace from the template
+trim = true
+# changelog footer
+footer = """
+<!-- generated by git-cliff -->
+"""
+
+[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 parsing and grouping commits
+commit_parsers = [
+    { message = "^.*: add", group = "Added" },
+    { message = "^.*: support", group = "Added" },
+    { message = "^.*: remove", group = "Removed" },
+    { message = "^.*: delete", group = "Removed" },
+    { message = "^test", group = "Fixed" },
+    { message = "^fix", group = "Fixed" },
+    { message = "^.*: fix", group = "Fixed" },
+    { message = "^.*", group = "Changed" },
+]
+# protect breaking changes from being skipped due to matching a skipping commit_parser
+protect_breaking_commits = false
+# filter out the commits that are not matched by commit parsers
+filter_commits = true
+# 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/newest order
+sort_commits = "oldest"

.github/fixtures/test-keep-a-changelog-links-current-arg/commit.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -e
+
+GIT_COMMITTER_DATE="2021-01-23 01:23:45" git commit --allow-empty -m "feat: add feature 1"
+git tag v0.1.0
+
+GIT_COMMITTER_DATE="2021-01-24 01:23:46" git commit --allow-empty -m "feat: add feature 2"
+git tag v0.2.0

.github/fixtures/test-keep-a-changelog-links-current-arg/expected.md

@@ -0,0 +1,14 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.2.0](https://github.com/dummy/dummy/compare/v0.1.0...v0.2.0) - 2021-01-24
+
+### Added
+
+- Add feature 2
+
+<!-- generated by git-cliff -->

.github/fixtures/test-keep-a-changelog-links-latest-arg/cliff.toml

@@ -0,0 +1,77 @@
+[changelog]
+# changelog header
+header = """
+# Changelog\n
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).\n
+"""
+# template for the changelog body
+# https://keats.github.io/tera/docs/#introduction
+body = """
+{% if version %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/compare/{{ previous.version }}...{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% else %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/releases/tag/{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% endif %}\
+    {% endif %}\
+{% else %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [Unreleased](https://github.com/dummy/dummy/compare/{{ previous.version }}...HEAD)
+      {% else %}\
+          ## [Unreleased]
+      {% endif %}\
+    {% else %}\
+        ## [Unreleased]
+    {% endif %}\
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | upper_first }}
+    {% for commit in commits %}
+        - {{ commit.message | upper_first }}\
+    {% endfor %}
+{% endfor %}\n
+"""
+# remove the leading and trailing whitespace from the template
+trim = true
+# changelog footer
+footer = """
+<!-- generated by git-cliff -->
+"""
+
+[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 parsing and grouping commits
+commit_parsers = [
+    { message = "^.*: add", group = "Added" },
+    { message = "^.*: support", group = "Added" },
+    { message = "^.*: remove", group = "Removed" },
+    { message = "^.*: delete", group = "Removed" },
+    { message = "^test", group = "Fixed" },
+    { message = "^fix", group = "Fixed" },
+    { message = "^.*: fix", group = "Fixed" },
+    { message = "^.*", group = "Changed" },
+]
+# protect breaking changes from being skipped due to matching a skipping commit_parser
+protect_breaking_commits = false
+# filter out the commits that are not matched by commit parsers
+filter_commits = true
+# 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/newest order
+sort_commits = "oldest"

.github/fixtures/test-keep-a-changelog-links-latest-arg/commit.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -e
+
+GIT_COMMITTER_DATE="2021-01-23 01:23:45" git commit --allow-empty -m "feat: add feature 1"
+git tag v0.1.0
+
+GIT_COMMITTER_DATE="2021-01-24 01:23:46" git commit --allow-empty -m "feat: add feature 2"
+git tag v0.2.0
+
+GIT_COMMITTER_DATE="2021-01-25 01:23:47" git commit --allow-empty -m "fix: fix feature 1"

.github/fixtures/test-keep-a-changelog-links-latest-arg/expected.md

@@ -0,0 +1,14 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.2.0](https://github.com/dummy/dummy/compare/v0.1.0...v0.2.0) - 2021-01-24
+
+### Added
+
+- Add feature 2
+
+<!-- generated by git-cliff -->

.github/fixtures/test-keep-a-changelog-links-no-tags/cliff.toml

@@ -0,0 +1,77 @@
+[changelog]
+# changelog header
+header = """
+# Changelog\n
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).\n
+"""
+# template for the changelog body
+# https://keats.github.io/tera/docs/#introduction
+body = """
+{% if version %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/compare/{{ previous.version }}...{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% else %}\
+          ## [{{ version | trim_start_matches(pat="v") }}](https://github.com/dummy/dummy/releases/tag/{{ version }}) - {{ timestamp | date(format="%Y-%m-%d") }}
+      {% endif %}\
+    {% endif %}\
+{% else %}\
+    {% if previous %}\
+      {% if previous.version %}\
+          ## [Unreleased](https://github.com/dummy/dummy/compare/{{ previous.version }}...HEAD)
+      {% else %}\
+          ## [Unreleased]
+      {% endif %}\
+    {% else %}\
+        ## [Unreleased]
+    {% endif %}\
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | upper_first }}
+    {% for commit in commits %}
+        - {{ commit.message | upper_first }}\
+    {% endfor %}
+{% endfor %}\n
+"""
+# remove the leading and trailing whitespace from the template
+trim = true
+# changelog footer
+footer = """
+<!-- generated by git-cliff -->
+"""
+
+[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 parsing and grouping commits
+commit_parsers = [
+    { message = "^.*: add", group = "Added" },
+    { message = "^.*: support", group = "Added" },
+    { message = "^.*: remove", group = "Removed" },
+    { message = "^.*: delete", group = "Removed" },
+    { message = "^test", group = "Fixed" },
+    { message = "^fix", group = "Fixed" },
+    { message = "^.*: fix", group = "Fixed" },
+    { message = "^.*", group = "Changed" },
+]
+# protect breaking changes from being skipped due to matching a skipping commit_parser
+protect_breaking_commits = false
+# filter out the commits that are not matched by commit parsers
+filter_commits = true
+# 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/newest order
+sort_commits = "oldest"

.github/fixtures/test-keep-a-changelog-links-no-tags/commit.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -e
+
+GIT_COMMITTER_DATE="2021-01-23 01:23:45" git commit --allow-empty -m "feat: add feature 1"
+
+GIT_COMMITTER_DATE="2021-01-24 01:23:46" git commit --allow-empty -m "feat: add feature 2"
+
+GIT_COMMITTER_DATE="2021-01-25 01:23:47" git commit --allow-empty -m "fix: fix feature 1"

.github/fixtures/test-keep-a-changelog-links-no-tags/expected.md

@@ -0,0 +1,19 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- Add feature 1
+- Add feature 2
+
+### Fixed
+
+- Fix feature 1
+
+<!-- generated by git-cliff -->