Repository: MarcoIeni/release-plz (rust)

Issue:
Read git-cliff config file
## Motivations

We use [git-cliff](https://github.com/orhun/git-cliff) to generate the changelog. However, we use a fixed configuration.
It would be nice to allow users to specify their own git-cliff config file.


Pull request description:
feat: read custom git cliff config
<!-- Please explain the changes you made -->

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Please, make sure:
- you have read the contributing guidelines:
  https://github.com/MarcoIeni/release-plz/blob/main/docs/CONTRIBUTING.md
- you have formatted the code using rustfmt:
  https://github.com/rust-lang/rustfmt
- you have checked that all tests pass, by running `cargo test --all`
- you have updated the changelog (if needed):
  https://github.com/MarcoIeni/release-plz/blob/main/CHANGELOG.md
-->
Close #30 

Patch:
diff --git a/Cargo.lock b/Cargo.lock
index 10d038f4..678d9dd8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -789,6 +789,15 @@ dependencies = [
  "generic-array 0.14.5",
 ]
 
+[[package]]
+name = "dirs"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca3aa72a6f96ea37bbc5aa912f6788242832f75369bdfdadcb0e38423f100059"
+dependencies = [
+ "dirs-sys",
+]
+
 [[package]]
 name = "dirs-next"
 version = "2.0.0"
@@ -799,6 +808,17 @@ dependencies = [
  "dirs-sys-next",
 ]
 
+[[package]]
+name = "dirs-sys"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b1d1d91c932ef41c0f2663aa8b0ca0342d444d842c06914aa0a7e352d0bada6"
+dependencies = [
+ "libc",
+ "redox_users",
+ "winapi",
+]
+
 [[package]]
 name = "dirs-sys-next"
 version = "0.1.2"
@@ -2329,6 +2349,8 @@ dependencies = [
  "anyhow",
  "chrono",
  "clap 3.1.17",
+ "dirs",
+ "git-cliff-core",
  "release_plz_core",
  "secrecy",
  "tokio",
diff --git a/README.md b/README.md
index 68c5a466..d4de8ba5 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,13 @@ subtle manual mistakes you can make when releasing from your terminal.
 
 You can release all the unpublished packages by running `release-plz release`.
 
+## Changelog format
+
+Release-plz generates the changelog by using [git-cliff](https://github.com/orhun/git-cliff).
+By default, release-plz uses the [keep a changelog](https://keepachangelog.com/en/1.1.0/) format.
+You can customize the changelog format, by providing a git-cliff configuration
+file with the `--changelog-config` argument.
+
 ## Similar projects
 
 - [release-please](https://github.com/googleapis/release-please): release-plz is inspired by release-please,
@@ -93,3 +100,4 @@ Parts of the codebase are inspired by:
 - [cargo-workspaces](https://github.com/pksunkara/cargo-workspaces)
 - [cargo-release](https://github.com/crate-ci/cargo-release)
 - [cargo-edit](https://github.com/killercup/cargo-edit)
+- [git-cliff](https://github.com/orhun/git-cliff)
diff --git a/crates/release_plz/Cargo.toml b/crates/release_plz/Cargo.toml
index 67c2633e..28d595e6 100644
--- a/crates/release_plz/Cargo.toml
+++ b/crates/release_plz/Cargo.toml
@@ -23,3 +23,5 @@ tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 tracing-log = "0.1"
 url = "2"
+dirs = "4"
+git-cliff-core = "0.7"
diff --git a/crates/release_plz/src/args/update.rs b/crates/release_plz/src/args/update.rs
index 0d8ed431..4024c7d0 100644
--- a/crates/release_plz/src/args/update.rs
+++ b/crates/release_plz/src/args/update.rs
@@ -2,6 +2,7 @@ use std::path::PathBuf;
 
 use anyhow::Context;
 use chrono::{Date, NaiveDate, Utc};
+use git_cliff_core::config::Config as GitCliffConfig;
 use release_plz_core::{ChangelogRequest, UpdateRequest, CARGO_TOML};
 
 use super::local_manifest;
@@ -45,6 +46,16 @@ pub struct Update {
     /// If this flag is not specified, only update the workspace packages by running `cargo update --workspace`.
     #[clap(short, long)]
     update_deps: bool,
+    /// Path to the git cliff configuration file.
+    /// If not provided, `dirs::config_dir()/git-cliff/cliff.toml` is used if present.
+    #[clap(
+        long,
+        env = "GIT_CLIFF_CONFIG",
+        value_name = "PATH",
+        conflicts_with("no-changelog"),
+        forbid_empty_values(true)
+    )]
+    changelog_config: Option<PathBuf>,
 }
 
 impl Update {
@@ -70,7 +81,11 @@ impl Update {
                 })
                 .transpose()?
                 .map(|date| Date::<Utc>::from_utc(date, Utc));
-            update = update.with_changelog(ChangelogRequest { release_date });
+            let changelog_req = ChangelogRequest {
+                release_date,
+                changelog_config: self.changelog_config()?,
+            };
+            update = update.with_changelog(changelog_req);
         }
         if let Some(package) = &self.package {
             update = update.with_single_package(package.clone());
@@ -81,6 +96,34 @@ impl Update {
         if self.update_deps {
             update = update.with_update_dependencies(true);
         }
+
         Ok(update)
     }
+
+    fn changelog_config(&self) -> anyhow::Result<Option<GitCliffConfig>> {
+        let default_config_path = dirs::config_dir()
+            .context("cannot get config dir")?
+            .join("git-cliff")
+            .join(git_cliff_core::DEFAULT_CONFIG);
+
+        let path = match self.changelog_config.clone() {
+            Some(provided_path) => {
+                if provided_path.exists() {
+                    provided_path
+                } else {
+                    anyhow::bail!("cannot read {:?}", provided_path)
+                }
+            }
+            None => default_config_path,
+        };
+
+        // Parse the configuration file.
+        let config = if path.exists() {
+            Some(GitCliffConfig::parse(&path).context("failed to parse git cliff config file")?)
+        } else {
+            None
+        };
+
+        Ok(config)
+    }
 }
diff --git a/crates/release_plz_core/src/changelog.rs b/crates/release_plz_core/src/changelog.rs
index bf88955d..b8600177 100644
--- a/crates/release_plz_core/src/changelog.rs
+++ b/crates/release_plz_core/src/changelog.rs
@@ -20,12 +20,13 @@ pub const CHANGELOG_FILENAME: &str = "CHANGELOG.md";
 
 pub struct Changelog<'a> {
     release: Release<'a>,
+    config: Option<Config>,
 }
 
 impl Changelog<'_> {
     /// Generate the full changelog.
     pub fn generate(self) -> String {
-        let config = git_cliff_config();
+        let config = self.config.unwrap_or_else(default_git_cliff_config);
         let changelog = GitCliffChangelog::new(vec![self.release], &config)
             .expect("error while building changelog");
         let mut out = Vec::new();
@@ -37,7 +38,7 @@ impl Changelog<'_> {
 
     /// Update an existing changelog.
     pub fn prepend(self, old_changelog: impl Into<String>) -> String {
-        let config = git_cliff_config();
+        let config = self.config.unwrap_or_else(default_git_cliff_config);
         let changelog = GitCliffChangelog::new(vec![self.release], &config)
             .expect("error while building changelog");
         let mut out = Vec::new();
@@ -48,16 +49,17 @@ impl Changelog<'_> {
     }
 }
 
-fn git_cliff_config() -> Config {
+fn default_git_cliff_config() -> Config {
     Config {
-        changelog: changelog_config(),
-        git: git_config(),
+        changelog: default_changelog_config(),
+        git: default_git_config(),
     }
 }
 
 pub struct ChangelogBuilder {
     commits: Vec<String>,
     version: String,
+    config: Option<Config>,
     release_date: Option<Date<Utc>>,
 }
 
@@ -67,6 +69,7 @@ impl<'a> ChangelogBuilder {
             commits: commits.into_iter().map(|s| s.into()).collect(),
             version: version.into(),
             release_date: None,
+            config: None,
         }
     }
 
@@ -77,14 +80,26 @@ impl<'a> ChangelogBuilder {
         }
     }
 
+    pub fn with_config(self, config: Config) -> Self {
+        Self {
+            config: Some(config),
+            ..self
+        }
+    }
+
     pub fn build(self) -> Changelog<'static> {
+        let git_config = self
+            .config
+            .clone()
+            .map(|c| c.git)
+            .unwrap_or_else(default_git_config);
         let release_date = self.release_timestamp();
         let commits = self
             .commits
             .clone()
             .into_iter()
             .map(|c| Commit::new("id".to_string(), c))
-            .filter_map(|c| c.process(&git_config()).ok())
+            .filter_map(|c| c.process(&git_config).ok())
             .collect();
 
         Changelog {
@@ -95,6 +110,7 @@ impl<'a> ChangelogBuilder {
                 timestamp: release_date,
                 previous: None,
             },
+            config: self.config,
         }
     }
 
@@ -105,7 +121,7 @@ impl<'a> ChangelogBuilder {
     }
 }
 
-fn git_config() -> GitConfig {
+fn default_git_config() -> GitConfig {
     GitConfig {
         conventional_commits: Some(true),
         filter_unconventional: Some(false),
@@ -187,7 +203,7 @@ fn commit_parsers() -> Vec<CommitParser> {
     ]
 }
 
-fn changelog_config() -> ChangelogConfig {
+fn default_changelog_config() -> ChangelogConfig {
     ChangelogConfig {
         header: Some(String::from(CHANGELOG_HEADER)),
         body: Some(String::from(
diff --git a/crates/release_plz_core/src/next_ver.rs b/crates/release_plz_core/src/next_ver.rs
index 2c3aecab..7df0b60a 100644
--- a/crates/release_plz_core/src/next_ver.rs
+++ b/crates/release_plz_core/src/next_ver.rs
@@ -11,6 +11,7 @@ use cargo_edit::{upgrade_requirement, LocalManifest, VersionExt};
 use cargo_metadata::{Package, Version};
 use chrono::{Date, Utc};
 use fs_extra::dir;
+use git_cliff_core::config::Config as GitCliffConfig;
 use git_cmd::{self, Repo};
 use std::{
     fs, io,
@@ -38,10 +39,11 @@ pub struct UpdateRequest {
     update_dependencies: bool,
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone)]
 pub struct ChangelogRequest {
     /// When the new release is published. If unspecified, current date is used.
     pub release_date: Option<Date<Utc>>,
+    pub changelog_config: Option<GitCliffConfig>,
 }
 
 fn canonical_local_manifest(local_manifest: &Path) -> io::Result<PathBuf> {
@@ -143,7 +145,7 @@ pub fn next_versions(
         local_project,
         &registry_packages,
         &repository.repo,
-        input.changelog_req,
+        input.changelog_req.clone(),
     )?;
     Ok((packages_to_update, repository))
 }
@@ -214,7 +216,7 @@ impl UpdateResult {
         package: &Package,
     ) -> anyhow::Result<UpdateResult> {
         let changelog = changelog_req
-            .map(|r| get_changelog(commits, &version, r.release_date, package))
+            .map(|r| get_changelog(commits, &version, Some(r), package))
             .transpose()?;
 
         Ok(UpdateResult { version, changelog })
@@ -241,7 +243,7 @@ fn packages_to_update(
         if next_version != current_version || !diff.registry_package_exists {
             info!("{}: next version is {next_version}", p.name);
             let update_result =
-                UpdateResult::new(diff.commits.clone(), next_version, changelog_req, p)?;
+                UpdateResult::new(diff.commits.clone(), next_version, changelog_req.clone(), p)?;
 
             packages_to_update.push((p.clone(), update_result));
         } else if diff.is_version_published {
@@ -297,7 +299,7 @@ fn dependent_packages(
             );
             Ok((
                 p.clone(),
-                UpdateResult::new(vec![change], next_version, changelog_req, p)?,
+                UpdateResult::new(vec![change], next_version, changelog_req.clone(), p)?,
             ))
         })
         .collect::<anyhow::Result<Vec<_>>>()?;
@@ -307,12 +309,17 @@ fn dependent_packages(
 fn get_changelog(
     commits: Vec<String>,
     next_version: &Version,
-    release_date: Option<Date<Utc>>,
+    changelog_req: Option<ChangelogRequest>,
     package: &Package,
 ) -> anyhow::Result<String> {
     let mut changelog_builder = ChangelogBuilder::new(commits, next_version.to_string());
-    if let Some(release_date) = release_date {
-        changelog_builder = changelog_builder.with_release_date(release_date)
+    if let Some(changelog_req) = changelog_req {
+        if let Some(release_date) = changelog_req.release_date {
+            changelog_builder = changelog_builder.with_release_date(release_date)
+        }
+        if let Some(config) = changelog_req.changelog_config {
+            changelog_builder = changelog_builder.with_config(config)
+        }
     }
     let new_changelog = changelog_builder.build();
     let changelog = match fs::read_to_string(package.changelog_path()?) {


Test patch:
diff --git a/crates/release_plz_core/tests/all/helpers/comparison_test.rs b/crates/release_plz_core/tests/all/helpers/comparison_test.rs
index 1bc41a3a..a2ebe8a7 100644
--- a/crates/release_plz_core/tests/all/helpers/comparison_test.rs
+++ b/crates/release_plz_core/tests/all/helpers/comparison_test.rs
@@ -48,6 +48,7 @@ impl ComparisonTest {
             .unwrap()
             .with_changelog(ChangelogRequest {
                 release_date: Some(Utc.ymd(2015, 5, 15)),
+                changelog_config: None,
             })
             .with_registry_project_manifest(self.registry_project_manfifest())
             .unwrap()