lib.rs: Replace top-level `unwrap()`s with `Result`s

Add a new `Error` type that we can return in the failure case. Still
need to work out how to handle errors inside the diff callback.

2 files changed, 21 insertions, 7 deletions

diff --git a/src/lib.rs b/src/lib.rs
index bc3c9b0..0b64b22 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,6 +3,14 @@
 use std::io::Write;
 
 use git2::{Repository, Tree};
+use thiserror::Error;
+
+
+#[derive(Error, Debug)]
+pub enum Error {
+    #[error(transparent)]
+    Git(#[from] git2::Error),
+}
 
 
 pub struct Todos<'a> {
@@ -10,8 +18,12 @@ pub struct Todos<'a> {
 }
 
 impl Todos<'_> {
-    pub fn write_since<W: Write>(&self, tree: Tree<'_>, write_to: &mut W) {
-        let diff = self.repo.diff_tree_to_workdir(Some(&tree), None).unwrap();
+    pub fn write_since<W: Write>(
+        &self,
+        tree: Tree<'_>,
+        write_to: &mut W,
+    ) -> Result<(), Error> {
+        let diff = self.repo.diff_tree_to_workdir(Some(&tree), None)?;
 
         diff.foreach(
             &mut |_file, _progress| {
@@ -45,12 +57,14 @@ impl Todos<'_> {
                     true
                 }
             ),
-        ).unwrap();
+        )?;
+
+        Ok(())
     }
 
-    pub fn master_tree(&self) -> Tree<'_> {
-        let master = self.repo.find_branch("master", git2::BranchType::Local).unwrap();
+    pub fn master_tree(&self) -> Result<Tree<'_>, Error> {
+        let master = self.repo.find_branch("master", git2::BranchType::Local)?;
 
-        master.get().peel_to_tree().unwrap()
+        Ok(master.get().peel_to_tree()?)
     }
 }
diff --git a/src/main.rs b/src/main.rs
index 48e8f5d..f743256 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -9,5 +9,5 @@ fn main() {
     let repo = Repository::open(".").unwrap();
 
     let todos = Todos { repo: &repo };
-    todos.write_since(todos.master_tree(), &mut std::io::stdout());
+    todos.write_since(todos.master_tree().unwrap(), &mut std::io::stdout()).unwrap();
 }