feat(worktree): add base bindings and api

lib/src/bindings/worktree.dart

@@ -0,0 +1,94 @@
+import 'dart:ffi';
+import 'package:ffi/ffi.dart';
+import 'package:libgit2dart/libgit2dart.dart';
+import 'libgit2_bindings.dart';
+import '../error.dart';
+import '../util.dart';
+
+/// Add a new working tree.
+///
+/// Add a new working tree for the repository, that is create the required
+/// data structures inside the repository and check out the current HEAD at path.
+///
+/// Throws a [LibGit2Error] if error occured.
+Pointer<git_worktree> create(
+  Pointer<git_repository> repo,
+  String name,
+  String path,
+) {
+  final out = calloc<Pointer<git_worktree>>();
+  final nameC = name.toNativeUtf8().cast<Int8>();
+  final pathC = path.toNativeUtf8().cast<Int8>();
+  final error = libgit2.git_worktree_add(out, repo, nameC, pathC, nullptr);
+
+  calloc.free(nameC);
+  calloc.free(pathC);
+
+  if (error < 0) {
+    throw LibGit2Error(libgit2.git_error_last());
+  } else {
+    return out.value;
+  }
+}
+
+/// Lookup a working tree by its name for a given repository.
+///
+/// Throws a [LibGit2Error] if error occured.
+Pointer<git_worktree> lookup(Pointer<git_repository> repo, String name) {
+  final out = calloc<Pointer<git_worktree>>();
+  final nameC = name.toNativeUtf8().cast<Int8>();
+  final error = libgit2.git_worktree_lookup(out, repo, nameC);
+
+  calloc.free(nameC);
+
+  if (error < 0) {
+    throw LibGit2Error(libgit2.git_error_last());
+  } else {
+    return out.value;
+  }
+}
+
+/// Prune working tree.
+///
+/// Prune the working tree, that is remove the git data structures on disk.
+///
+/// Throws a [LibGit2Error] if error occured.
+void prune(Pointer<git_worktree> wt) {
+  final error = libgit2.git_worktree_prune(wt, nullptr);
+
+  if (error < 0) {
+    throw LibGit2Error(libgit2.git_error_last());
+  }
+}
+
+/// List names of linked working trees.
+///
+/// Throws a [LibGit2Error] if error occured.
+List<String> list(Pointer<git_repository> repo) {
+  final out = calloc<git_strarray>();
+  final error = libgit2.git_worktree_list(out, repo);
+  final result = <String>[];
+
+  if (error < 0) {
+    throw LibGit2Error(libgit2.git_error_last());
+  } else {
+    for (var i = 0; i < out.ref.count; i++) {
+      result.add(out.ref.strings[i].cast<Utf8>().toDartString());
+    }
+    calloc.free(out);
+    return result;
+  }
+}
+
+/// Retrieve the name of the worktree.
+String name(Pointer<git_worktree> wt) {
+  return libgit2.git_worktree_name(wt).cast<Utf8>().toDartString();
+}
+
+/// Retrieve the filesystem path for the worktree.
+String path(Pointer<git_worktree> wt) {
+  return libgit2.git_worktree_path(wt).cast<Utf8>().toDartString();
+}
+
+/// Free a previously allocated worktree.
+void free(Pointer<git_worktree> wt) => libgit2.git_worktree_free(wt);