feat(git): improve the set commit range error

git-cliff-core/src/error.rs

@@ -14,6 +14,13 @@ pub enum Error {
 	#[cfg(feature = "repo")]
 	#[error("Git error: `{0}`")]
 	GitError(#[from] git2::Error),
+	/// Error that may occur when failed to set a commit range.
+	#[cfg(feature = "repo")]
+	#[error(
+		"Failed to set the commit range: {1}
+{0:?} is not a valid commit range. Did you provide the correct arguments?"
+	)]
+	SetCommitRangeError(String, #[source] git2::Error),
 	/// Error variant that represents other repository related errors.
 	#[cfg(feature = "repo")]
 	#[error("Git repository error: `{0}`")]

git-cliff-core/src/repo.rs

@@ -22,6 +22,7 @@ use lazy_regex::{
 };
 use std::io;
 use std::path::PathBuf;
+use std::result::Result as StdResult;
 use url::Url;
 
 /// Regex for replacing the signature part of a tag message.
@@ -83,27 +84,43 @@ impl Repository {
 		path
 	}
 
-	/// Parses and returns the commits.
+	/// Sets the range for the commit search.
 	///
-	/// Sorts the commits by their time.
-	pub fn commits(
-		&self,
+	/// When a single SHA is provided as the range, start from the
+	/// root.
+	fn set_commit_range(
+		revwalk: &mut git2::Revwalk<'_>,
 		range: Option<&str>,
-		include_path: Option<Vec<Pattern>>,
-		exclude_path: Option<Vec<Pattern>>,
-	) -> Result<Vec<Commit>> {
-		let mut revwalk = self.inner.revwalk()?;
-		revwalk.set_sorting(Sort::TOPOLOGICAL)?;
+	) -> StdResult<(), git2::Error> {
 		if let Some(range) = range {
 			if range.contains("..") {
 				revwalk.push_range(range)?;
 			} else {
-				// When a single SHA is provided as the "range", start from the root.
 				revwalk.push(Oid::from_str(range)?)?;
 			}
 		} else {
 			revwalk.push_head()?;
 		}
+		Ok(())
+	}
+
+	/// Parses and returns the commits.
+	///
+	/// Sorts the commits by their time.
+	pub fn commits(
+		&self,
+		range: Option<&str>,
+		include_path: Option<Vec<Pattern>>,
+		exclude_path: Option<Vec<Pattern>>,
+	) -> Result<Vec<Commit>> {
+		let mut revwalk = self.inner.revwalk()?;
+		revwalk.set_sorting(Sort::TOPOLOGICAL)?;
+		Self::set_commit_range(&mut revwalk, range).map_err(|e| {
+			Error::SetCommitRangeError(
+				range.map(String::from).unwrap_or_else(|| "?".to_string()),
+				e,
+			)
+		})?;
 		let mut commits: Vec<Commit> = revwalk
 			.filter_map(|id| id.ok())
 			.filter_map(|id| self.inner.find_commit(id).ok())