test: add tests for DiffService

Packages/io.savolainen.unitygit-tests/Core/Services/DiffServiceTests.cs

@@ -0,0 +1,99 @@
+using System.IO;
+using System.Text;
+using LibGit2Sharp;
+using NSubstitute;
+using NUnit.Framework;
+using UnityEngine;
+using UnityGit.Core.Services;
+
+namespace UnityGit.Tests.Core.Services
+{
+    [TestFixture]
+    public class DiffServiceTests
+    {
+        private const string FilePath = "test.txt";
+
+        private DiffService _diffService;
+        private IRepository _repository;
+        private DiffService.InvokeDiffToolDelegate _invokeDiffDelegate;
+        private TreeEntry _treeEntry;
+
+        [SetUp]
+        public void Setup()
+        {
+            _repository = Substitute.For<IRepository>();
+
+            var head = Substitute.For<Branch>();
+            _repository.Head.Returns(head);
+            var tip = Substitute.For<Commit>();
+            head.Tip.Returns(tip);
+            _treeEntry = Substitute.For<TreeEntry>();
+            tip[FilePath].Returns(_treeEntry);
+
+            _invokeDiffDelegate = Substitute.For<DiffService.InvokeDiffToolDelegate>();
+            _diffService = new DiffService(_invokeDiffDelegate);
+        }
+
+        [Test]
+        public void DiffFile_WhenBlobIsNull_ShouldNotInvokeDiffTool()
+        {
+            _treeEntry.Target.Returns((Blob) null);
+
+            _diffService.DiffFile(_repository, FilePath);
+
+            _invokeDiffDelegate.DidNotReceive().Invoke(
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<string>(),
+                Arg.Any<string>()
+            );
+        }
+
+        [Test]
+        public void DiffFile_WhenBlobExists_ShouldInvokeDiffTool()
+        {
+            var repositoryInfo = Substitute.For<RepositoryInformation>();
+            repositoryInfo.WorkingDirectory.Returns("/repo");
+            _repository.Info.Returns(repositoryInfo);
+
+            var blob = Substitute.For<Blob>();
+            _treeEntry.Target.Returns(blob);
+
+            var contentStream = new MemoryStream(Encoding.UTF8.GetBytes("Test Content"));
+            blob.GetContentStream().Returns(contentStream);
+
+            _diffService.DiffFile(_repository, FilePath);
+
+            var headFilePath = Path.Combine(Application.temporaryCachePath, "HEAD");
+            var currentFilePath = Path.Combine("/repo", FilePath);
+
+            _invokeDiffDelegate.Received(1).Invoke(
+                "HEAD",
+                headFilePath,
+                "Current",
+                currentFilePath,
+                null,
+                null
+            );
+        }
+
+        [Test]
+        public void DiffFile_ShouldWriteBlobContentToFile()
+        {
+            var blob = Substitute.For<Blob>();
+            _treeEntry.Target.Returns(blob);
+
+            var contentStream = new MemoryStream(Encoding.UTF8.GetBytes("Test Content"));
+            blob.GetContentStream().Returns(contentStream);
+
+            _diffService.DiffFile(_repository, FilePath);
+
+            var headFilePath = Path.Combine(Application.temporaryCachePath, "HEAD");
+            Assert.IsTrue(File.Exists(headFilePath));
+            var fileContent = File.ReadAllText(headFilePath);
+            Assert.AreEqual("Test Content", fileContent);
+        }
+    }
+}

Packages/io.savolainen.unitygit/Core/Services/DiffService.cs

@@ -1,5 +1,6 @@
 using System.IO;
 using System.Text;
+using JetBrains.Annotations;
 using LibGit2Sharp;
 using UnityEditor;
 using UnityEngine;
@@ -13,6 +14,25 @@ public interface IDiffService
 
     public sealed class DiffService : IDiffService
     {
+        public delegate string InvokeDiffToolDelegate(
+            string leftTitle,
+            string leftFile,
+            string rightTitle,
+            string rightFile,
+            string ancestorTitle,
+            string ancestorFile
+        );
+
+        private readonly InvokeDiffToolDelegate _invokeDiffDelegate;
+
+        [PublicAPI]
+        public DiffService() : this(EditorUtility.InvokeDiffTool) {}
+
+        public DiffService(InvokeDiffToolDelegate invokeDiffDelegate)
+        {
+            _invokeDiffDelegate = invokeDiffDelegate;
+        }
+
         public void DiffFile(IRepository repository, string filePath)
         {
             var headFilePath = Path.Combine(Application.temporaryCachePath, "HEAD");
@@ -29,7 +49,7 @@ public void DiffFile(IRepository repository, string filePath)
 
             var currentFilePath = Path.Combine(repository.Info.WorkingDirectory, filePath);
 
-            EditorUtility.InvokeDiffTool(
+            _invokeDiffDelegate(
                 "HEAD",
                 headFilePath,
                 "Current",