Add zero byte check and tests

osu.Game.Tests/Editing/Checks/CheckZeroByteFilesTest.cs

@@ -0,0 +1,86 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using Moq;
+using NUnit.Framework;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Edit.Checks;
+using osu.Game.Rulesets.Objects;
+using FileInfo = osu.Game.IO.FileInfo;
+
+namespace osu.Game.Tests.Editing.Checks
+{
+    [TestFixture]
+    public class CheckZeroByteFilesTest
+    {
+        private CheckZeroByteFiles check;
+        private IBeatmap beatmap;
+
+        [SetUp]
+        public void Setup()
+        {
+            check = new CheckZeroByteFiles();
+            beatmap = new Beatmap<HitObject>
+            {
+                BeatmapInfo = new BeatmapInfo
+                {
+                    BeatmapSet = new BeatmapSetInfo
+                    {
+                        Files = new List<BeatmapSetFileInfo>(new[]
+                        {
+                            new BeatmapSetFileInfo
+                            {
+                                Filename = "abc123.jpg",
+                                FileInfo = new FileInfo { Hash = "abcdef" }
+                            }
+                        })
+                    }
+                }
+            };
+        }
+
+        [Test]
+        public void TestNonZeroBytes()
+        {
+            Assert.IsEmpty(check.Run(getContext(byteLength: 44)));
+        }
+
+        [Test]
+        public void TestZeroBytes()
+        {
+            var issues = check.Run(getContext(byteLength: 0)).ToList();
+
+            Assert.That(issues, Has.Count.EqualTo(1));
+            Assert.That(issues.Single().Template is CheckZeroByteFiles.IssueTemplateZeroBytes);
+        }
+
+        [Test]
+        public void TestMissing()
+        {
+            Assert.IsEmpty(check.Run(getContextMissing()));
+        }
+
+        private BeatmapVerifierContext getContext(long byteLength)
+        {
+            var mockStream = new Mock<Stream>();
+            mockStream.Setup(s => s.Length).Returns(byteLength);
+
+            var mockWorkingBeatmap = new Mock<IWorkingBeatmap>();
+            mockWorkingBeatmap.Setup(w => w.GetStream(It.IsAny<string>())).Returns(mockStream.Object);
+
+            return new BeatmapVerifierContext(beatmap, mockWorkingBeatmap.Object);
+        }
+
+        private BeatmapVerifierContext getContextMissing()
+        {
+            var mockWorkingBeatmap = new Mock<IWorkingBeatmap>();
+            mockWorkingBeatmap.Setup(w => w.GetStream(It.IsAny<string>())).Returns((Stream)null);
+
+            return new BeatmapVerifierContext(beatmap, mockWorkingBeatmap.Object);
+        }
+    }
+}

osu.Game/Rulesets/Edit/BeatmapVerifier.cs

@@ -25,6 +25,9 @@ namespace osu.Game.Rulesets.Edit
             new CheckMutedObjects(),
             new CheckFewHitsounds(),
 
+            // Files
+            new CheckZeroByteFiles(),
+
             // Compose
             new CheckUnsnappedObjects(),
             new CheckConcurrentObjects()

osu.Game/Rulesets/Edit/Checks/CheckZeroByteFiles.cs

@@ -0,0 +1,41 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.IO;
+using osu.Game.Rulesets.Edit.Checks.Components;
+
+namespace osu.Game.Rulesets.Edit.Checks
+{
+    public class CheckZeroByteFiles : ICheck
+    {
+        public CheckMetadata Metadata => new CheckMetadata(CheckCategory.Files, "Zero-byte files");
+
+        public IEnumerable<IssueTemplate> PossibleTemplates => new IssueTemplate[]
+        {
+            new IssueTemplateZeroBytes(this)
+        };
+
+        public IEnumerable<Issue> Run(BeatmapVerifierContext context)
+        {
+            var beatmapSet = context.Beatmap.BeatmapInfo.BeatmapSet;
+
+            foreach (var file in beatmapSet.Files)
+            {
+                Stream data = context.WorkingBeatmap.GetStream(file.FileInfo.StoragePath);
+                if (data?.Length == 0)
+                    yield return new IssueTemplateZeroBytes(this).Create(file.Filename);
+            }
+        }
+
+        public class IssueTemplateZeroBytes : IssueTemplate
+        {
+            public IssueTemplateZeroBytes(ICheck check)
+                : base(check, IssueType.Problem, "\"{0}\" is a 0-byte file.")
+            {
+            }
+
+            public Issue Create(string filename) => new Issue(this, filename);
+        }
+    }
+}