refactor!: use IterableMixin where possible

lib/src/index.dart

@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:ffi';
 import 'package:ffi/ffi.dart';
 import 'package:libgit2dart/libgit2dart.dart';
@@ -10,7 +11,7 @@ import 'git_types.dart';
 import 'repository.dart';
 import 'util.dart';
 
-class Index {
+class Index with IterableMixin<IndexEntry> {
   /// Initializes a new instance of [Index] class from provided
   /// pointer to index object in memory.
   ///
@@ -36,10 +37,7 @@ class Index {
   }
 
   /// Checks whether entry at provided [path] is in the git index or not.
-  bool contains(String path) => bindings.find(_indexPointer, path);
-
-  /// Returns the count of entries currently in the index.
-  int get count => bindings.entryCount(_indexPointer);
+  bool find(String path) => bindings.find(_indexPointer, path);
 
   /// Checks if the index contains entries representing file conflicts.
   bool get hasConflicts => bindings.hasConflicts(_indexPointer);
@@ -232,6 +230,9 @@ class Index {
 
   /// Releases memory allocated for index object.
   void free() => bindings.free(_indexPointer);
+
+  @override
+  Iterator<IndexEntry> get iterator => _IndexIterator(_indexPointer);
 }
 
 class IndexEntry {
@@ -307,3 +308,28 @@ class ConflictEntry {
   String toString() =>
       'ConflictEntry{ancestor: $ancestor, our: $our, their: $their}';
 }
+
+class _IndexIterator implements Iterator<IndexEntry> {
+  _IndexIterator(this._indexPointer) {
+    count = bindings.entryCount(_indexPointer);
+  }
+
+  final Pointer<git_index> _indexPointer;
+  IndexEntry? _currentEntry;
+  int _index = 0;
+  late final int count;
+
+  @override
+  IndexEntry get current => _currentEntry!;
+
+  @override
+  bool moveNext() {
+    if (_index == count) {
+      return false;
+    } else {
+      _currentEntry = IndexEntry(bindings.getByIndex(_indexPointer, _index));
+      _index++;
+      return true;
+    }
+  }
+}

lib/src/reflog.dart

@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:ffi';
 import 'bindings/libgit2_bindings.dart';
 import 'bindings/reflog.dart' as bindings;
@@ -5,7 +6,7 @@ import 'reference.dart';
 import 'signature.dart';
 import 'util.dart';
 
-class RefLog {
+class RefLog with IterableMixin<RefLogEntry> {
   /// Initializes a new instance of [RefLog] class from provided [Reference].
   ///
   /// Throws a [LibGit2Error] if error occured.
@@ -20,20 +21,6 @@ class RefLog {
   /// Pointer to memory address for allocated reflog object.
   late final Pointer<git_reflog> _reflogPointer;
 
-  /// Returns a list with entries of reference log.
-  List<RefLogEntry> get entries {
-    var log = <RefLogEntry>[];
-
-    for (var i = 0; i < count; i++) {
-      log.add(RefLogEntry(bindings.getByIndex(_reflogPointer, i)));
-    }
-
-    return log;
-  }
-
-  /// Returns the number of log entries in a reflog.
-  int get count => bindings.entryCount(_reflogPointer);
-
   /// Lookup an entry by its index.
   ///
   /// Requesting the reflog entry with an index of 0 (zero) will return
@@ -44,6 +31,9 @@ class RefLog {
 
   /// Releases memory allocated for reflog object.
   void free() => bindings.free(_reflogPointer);
+
+  @override
+  Iterator<RefLogEntry> get iterator => _RefLogIterator(_reflogPointer);
 }
 
 class RefLogEntry {
@@ -62,3 +52,30 @@ class RefLogEntry {
   @override
   String toString() => 'ReflogEntry{message: $message}';
 }
+
+class _RefLogIterator implements Iterator<RefLogEntry> {
+  _RefLogIterator(this._reflogPointer) {
+    _count = bindings.entryCount(_reflogPointer);
+  }
+
+  /// Pointer to memory address for allocated reflog object.
+  final Pointer<git_reflog> _reflogPointer;
+
+  RefLogEntry? _currentEntry;
+  int _index = 0;
+  late final int _count;
+
+  @override
+  RefLogEntry get current => _currentEntry!;
+
+  @override
+  bool moveNext() {
+    if (_index == _count) {
+      return false;
+    } else {
+      _currentEntry = RefLogEntry(bindings.getByIndex(_reflogPointer, _index));
+      _index++;
+      return true;
+    }
+  }
+}

lib/src/tag.dart

@@ -1,15 +1,14 @@
 import 'dart:ffi';
-
-import 'package:libgit2dart/libgit2dart.dart';
-
 import 'bindings/libgit2_bindings.dart';
 import 'bindings/tag.dart' as bindings;
 import 'bindings/object.dart' as object_bindings;
+import 'blob.dart';
 import 'commit.dart';
 import 'oid.dart';
 import 'repository.dart';
 import 'signature.dart';
 import 'git_types.dart';
+import 'tree.dart';
 import 'util.dart';
 
 class Tag {

lib/src/tree.dart

@@ -49,8 +49,7 @@ class Tree {
   ///
   /// If string [value] is provided, lookup is done by entry filename.
   ///
-  /// If provided string [value] is a path to file, lookup is done by path. In that case
-  /// returned object should be freed explicitly.
+  /// If provided string [value] is a path to file, lookup is done by path.
   TreeEntry operator [](Object value) {
     if (value is int) {
       return TreeEntry(bindings.getByIndex(_treePointer, value));