feat(reference): add ability to lookup reference by shorthand name

lib/src/bindings/reference.dart

@@ -65,6 +65,25 @@ Pointer<git_reference> lookup(Pointer<git_repository> repo, String name) {
   }
 }
 
+/// Lookup a reference by DWIMing its short name.
+///
+/// Apply the git precendence rules to the given shorthand to determine which reference
+/// the user is referring to.
+///
+/// Throws a [LibGit2Error] if error occured.
+Pointer<git_reference> lookupDWIM(Pointer<git_repository> repo, String name) {
+  final out = calloc<Pointer<git_reference>>();
+  final nameC = name.toNativeUtf8().cast<Int8>();
+  final error = libgit2.git_reference_dwim(out, repo, nameC);
+  calloc.free(nameC);
+
+  if (error < 0) {
+    throw LibGit2Error(libgit2.git_error_last());
+  } else {
+    return out.value;
+  }
+}
+
 /// Get the full name of a reference.
 String name(Pointer<git_reference> ref) {
   var result = calloc<Int8>();

lib/src/reference.dart

@@ -90,6 +90,19 @@ class Reference {
     _refPointer = bindings.lookup(repo, name);
   }
 
+  /// Initializes a new instance of the [Reference] class by
+  /// lookingup a reference by DWIMing it's short [name] in a repository.
+  ///
+  /// Should be freed with `free()` to release allocated memory.
+  ///
+  /// The name will be checked for validity.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  Reference.lookupDWIM(Pointer<git_repository> repo, String name) {
+    libgit2.git_libgit2_init();
+    _refPointer = bindings.lookupDWIM(repo, name);
+  }
+
   /// Pointer to memory address for allocated reference object.
   late Pointer<git_reference> _refPointer;
 

lib/src/repository.dart

@@ -227,6 +227,12 @@ class Repository {
   /// Throws a [LibGit2Error] if error occured.
   Reference getReference(String name) => Reference.lookup(_repoPointer, name);
 
+  /// Returns [Reference] object by lookingup a short [name] in repository.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  Reference getReferenceDWIM(String name) =>
+      Reference.lookupDWIM(_repoPointer, name);
+
   /// Checks if a reflog exists for the specified reference [name].
   ///
   /// Throws a [LibGit2Error] if error occured.