feat(args): add --with-commit argument for including custom commit …

…messages in changelog

README.md

@@ -155,6 +155,7 @@ git-cliff [FLAGS] [OPTIONS] [RANGE]
 -r, --repository <PATH>           Sets the git repository [env: REPOSITORY=]
     --include-path <PATTERN>...   Sets the path to include related commits [env: INCLUDE_PATH=]
     --exclude-path <PATTERN>...   Sets the path to exclude related commits [env: EXCLUDE_PATH=]
+    --with-commit <MSG>...        Sets custom commit messages to include in the changelog [env: WITH_COMMIT=]
 -p, --prepend <PATH>              Prepends entries to the given changelog file [env: PREPEND=
 -o, --output <PATH>               Writes output to the given file [env: OUTPUT=]
 -t, --tag <TAG>                   Sets the tag for the latest version [env: TAG=]
@@ -221,6 +222,18 @@ git cliff --include-path "**/*.toml" --include-path "*.md"
 git cliff --exclude-path ".github/*"
 ```
 
+Generate a changelog that includes yet unexisting commit messages:
+
+```sh
+commit_msg="chore(release): update CHANGELOG.md for 1.0.0"
+
+# You might need to include the commit messages that do not exist
+# for testing purposes or solving the chicken-egg problem.
+git cliff --with-commit "$commit_msg"
+
+git commit -m "$commit_msg"
+```
+
 Sort the commits inside sections:
 
 ```sh

git-cliff/src/args.rs

@@ -43,6 +43,9 @@ pub struct Opt {
 	/// Sets the path to exclude related commits.
 	#[structopt(long, env, value_name = "PATTERN")]
 	pub exclude_path: Option<Vec<Pattern>>,
+	/// Sets custom commit messages to include in the changelog.
+	#[structopt(long, env, value_name = "MSG")]
+	pub with_commit:  Option<Vec<String>>,
 	/// Prepends entries to the given changelog file.
 	#[structopt(short, long, env, value_name = "PATH")]
 	pub prepend:      Option<PathBuf>,

git-cliff/src/lib.rs

@@ -217,6 +217,17 @@ pub fn run(mut args: Opt) -> Result<()> {
 		}
 	}
 
+	// Add custom commit messages to the latest release.
+	if let Some(custom_commits) = args.with_commit {
+		if let Some(latest_release) = releases.iter_mut().last() {
+			custom_commits.iter().for_each(|commit_message| {
+				latest_release
+					.commits
+					.push(Commit::new(String::new(), commit_message.to_string()))
+			});
+		}
+	}
+
 	// Set the previous release if needed.
 	if args.latest {
 		if let Some((commit_id, version)) = tags.get_index(tags.len() - 2) {