🐛 Fix Position getter uninit LazyFileStream returning 0

SceneGate · Jul 15, 2024 · 34efc81 · 34efc81
1 parent e206c92
commit 34efc81
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Showing 2 changed files with 21 additions and 2 deletions.
diff --git a/src/Yarhl.UnitTests/IO/StreamFormat/LazyFileStreamTests.cs b/src/Yarhl.UnitTests/IO/StreamFormat/LazyFileStreamTests.cs
@@ -69,10 +69,29 @@ public void ConstructorSetFileLengthOrZero()
         }
 
         [Test]
-        public void GetPositionWithoutInitializeReturnsZero()
+        public void GetPositionWithoutInitializeReturnsSameAsSet()
         {
             using var stream = new LazyFileStream(tempFile, FileOpenMode.ReadWrite);
             Assert.That(stream.Position, Is.EqualTo(0));
+
+            stream.Position = 0x42;
+            Assert.That(stream.BaseStream, Is.Null);
+            Assert.That(stream.Position, Is.EqualTo(0x42));
+        }
+
+        [Test]
+        public void FileOpenedWithInitialPosition()
+        {
+            byte[] fileContent = { 0xFF, 0x42 };
+            File.WriteAllBytes(tempFile, fileContent);
+            using var stream = new LazyFileStream(tempFile, FileOpenMode.ReadWrite);
+            stream.Position = 1;
+
+            Assert.That(stream.BaseStream, Is.Null);
+            byte actual = (byte)stream.ReadByte();
+
+            Assert.That(actual, Is.EqualTo(fileContent[1]));
+            Assert.That(stream.Position, Is.EqualTo(2));
         }
 
         [Test]

diff --git a/src/Yarhl/IO/StreamFormat/LazyFileStream.cs b/src/Yarhl/IO/StreamFormat/LazyFileStream.cs
@@ -62,7 +62,7 @@ public LazyFileStream(string path, FileOpenMode mode)
         /// <inheritdoc/>
         public override long Position
         {
-            get => BaseStream?.Position ?? 0;
+            get => BaseStream?.Position ?? initialPosition;
             set
             {
                 if (BaseStream is null) {