feat: override toString with relevant information for debugging

lib/src/commit.dart

@@ -103,4 +103,7 @@ class Commit {
 
   /// Releases memory allocated for commit object.
   void free() => bindings.free(_commitPointer);
+
+  @override
+  String toString() => 'Commit{id: $id}';
 }

lib/src/index.dart

@@ -251,4 +251,8 @@ class ConflictEntry {
   ///
   /// Throws a [LibGit2Error] if error occured.
   void remove() => bindings.conflictRemove(_indexPointer, _path);
+
+  @override
+  String toString() =>
+      'ConflictEntry{ancestor: $ancestor, our: $our, their: $their}';
 }

lib/src/oid.dart

@@ -74,4 +74,7 @@ class Oid {
 
   @override
   int get hashCode => _oidPointer.address.hashCode;
+
+  @override
+  String toString() => 'Oid{sha: $sha}';
 }

lib/src/reflog.dart

@@ -58,4 +58,7 @@ class RefLogEntry {
 
   /// Returns the committer of this entry.
   Signature get committer => Signature(bindings.entryCommiter(_entryPointer));
+
+  @override
+  String toString() => 'ReflogEntry{message: $message}';
 }

lib/src/repository.dart

@@ -357,11 +357,11 @@ class Repository {
   /// Returns the list of commits starting from provided [sha] hex string.
   ///
   /// If [sorting] isn't provided default will be used (reverse chronological order, like in git).
-  List<Commit> log(String sha, [List<GitSort>? sorting]) {
+  List<Commit> log(String sha, [List<GitSort> sorting = const [GitSort.none]]) {
     final oid = Oid.fromSHA(this, sha);
     final walker = RevWalk(this);
 
-    walker.sorting(sorting ?? [GitSort.none]);
+    walker.sorting(sorting);
     walker.push(oid);
     final result = walker.walk();
 

lib/src/tree.dart

@@ -120,4 +120,7 @@ class TreeEntry {
 
   /// Releases memory allocated for tree entry object.
   void free() => bindings.entryFree(_treeEntryPointer);
+
+  @override
+  String toString() => 'TreeEntry{id: $id, name: $name}';
 }