From cc78e7945f4d3d06749b2c7d2f2651db5eba6c32 Mon Sep 17 00:00:00 2001
From: Aleksey Kulikov <skinny.mind@gmail.com>
Date: Fri, 14 Jan 2022 15:08:45 +0300
Subject: [PATCH] feat(index): add binding and API method for git_index_new
 (#33)

---
 lib/src/bindings/index.dart | 12 ++++++++++++
 lib/src/index.dart          |  8 ++++++++
 test/index_test.dart        |  4 ++++
 3 files changed, 24 insertions(+)

diff --git a/lib/src/bindings/index.dart b/lib/src/bindings/index.dart
index e1221c8..e7d7033 100644
--- a/lib/src/bindings/index.dart
+++ b/lib/src/bindings/index.dart
@@ -5,6 +5,18 @@ import 'package:libgit2dart/src/bindings/libgit2_bindings.dart';
 import 'package:libgit2dart/src/error.dart';
 import 'package:libgit2dart/src/util.dart';
 
+/// Create an in-memory index object.
+///
+/// This index object cannot be read/written to the filesystem, but may be
+/// used to perform in-memory index operations.
+///
+/// The index must be freed once it's no longer in use.
+Pointer<git_index> newInMemory() {
+  final out = calloc<Pointer<git_index>>();
+  libgit2.git_index_new(out);
+  return out.value;
+}
+
 /// Read index capabilities flags.
 int capabilities(Pointer<git_index> index) => libgit2.git_index_caps(index);
 
diff --git a/lib/src/index.dart b/lib/src/index.dart
index 3aaeeab..f493e07 100644
--- a/lib/src/index.dart
+++ b/lib/src/index.dart
@@ -14,6 +14,14 @@ class Index with IterableMixin<IndexEntry> {
   /// **IMPORTANT**: Should be freed to release allocated memory.
   const Index(this._indexPointer);
 
+  /// Creates an in-memory index object.
+  ///
+  /// This index object cannot be read/written to the filesystem, but may be
+  /// used to perform in-memory index operations.
+  ///
+  /// **IMPORTANT**: Should be freed to release allocated memory.
+  Index.newInMemory() : _indexPointer = bindings.newInMemory();
+
   final Pointer<git_index> _indexPointer;
 
   /// Pointer to memory address for allocated index object.
diff --git a/test/index_test.dart b/test/index_test.dart
index ede77cc..1b47d27 100644
--- a/test/index_test.dart
+++ b/test/index_test.dart
@@ -29,6 +29,10 @@ void main() {
     const fileSha = 'e69de29bb2d1d6434b8b29ae775ad8c2e48c5391';
     const featureFileSha = '9c78c21d6680a7ffebc76f7ac68cacc11d8f48bc';
 
+    test('creates new in memory index object', () {
+      expect(Index.newInMemory(), isA<Index>());
+    });
+
     test('returns full path to the index file on disk', () {
       expect(index.path, p.join(repo.path, 'index'));
     });