Refactor ResolveLinkTarget to TryResolveLinkTarget

xoofx · May 24, 2024 · 186c4e9 · 186c4e9
1 parent d9f3442
commit 186c4e9
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Showing 9 changed files with 52 additions and 21 deletions.
diff --git a/src/Zio.Tests/FileSystems/FileSystemEntryRedirect.cs b/src/Zio.Tests/FileSystems/FileSystemEntryRedirect.cs
@@ -125,9 +125,9 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
         _fs.CreateSymbolicLink(path, pathToTarget);
     }
 
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
-        return _fs.ResolveLinkTarget(linkPath);
+        return _fs.TryResolveLinkTarget(linkPath, out resolvedPath);
     }
 
     protected override IEnumerable<UPath> EnumeratePathsImpl(UPath path, string searchPattern, SearchOption searchOption, SearchTarget searchTarget)

diff --git a/src/Zio.Tests/FileSystems/TestPhysicalFileSystem.cs b/src/Zio.Tests/FileSystems/TestPhysicalFileSystem.cs
@@ -443,7 +443,8 @@ public void TestDirectorySymlink()
             fs.CreateSymbolicLink(pathDest, pathSource);
 
             // ResolveSymbolicLink
-            Assert.Equal(pathSource, fs.ResolveLinkTarget(pathDest));
+            Assert.True(fs.TryResolveLinkTarget(pathDest, out var resolvedPath));
+            Assert.Equal(pathSource, resolvedPath);
 
             // FileExists
             Assert.True(fs.FileExists(filePathDest));
@@ -491,7 +492,8 @@ public void TestFileSymlink()
             fs.CreateSymbolicLink(pathDest, pathSource);
 
             // ResolveSymbolicLink
-            Assert.Equal(pathSource, fs.ResolveLinkTarget(pathDest));
+            Assert.True(fs.TryResolveLinkTarget(pathDest, out var resolvedPath));
+            Assert.Equal(pathSource, resolvedPath);
 
             // FileExists
             Assert.True(fs.FileExists(pathDest));

diff --git a/src/Zio/FileSystems/ComposeFileSystem.cs b/src/Zio/FileSystems/ComposeFileSystem.cs
@@ -193,11 +193,16 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
     }
 
     /// <inheritdoc />
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
-        var path = FallbackSafe.ResolveLinkTarget(ConvertPathToDelegate(linkPath));
+        if (!FallbackSafe.TryResolveLinkTarget(ConvertPathToDelegate(linkPath), out var resolvedPathDelegate))
+        {
+            resolvedPath = default;
+            return false;
+        }
 
-        return path.HasValue ? ConvertPathFromDelegate(path.Value) : default(UPath?);
+        resolvedPath = ConvertPathFromDelegate(resolvedPathDelegate);
+        return true;
     }
 
     // ----------------------------------------------

diff --git a/src/Zio/FileSystems/FileSystem.cs b/src/Zio/FileSystems/FileSystem.cs
@@ -447,17 +447,18 @@ public void CreateSymbolicLink(UPath path, UPath pathToTarget)
 
 
     /// <inheritdoc />
-    public UPath? ResolveLinkTarget(UPath linkPath)
+    public bool TryResolveLinkTarget(UPath linkPath, out UPath resolvedPath)
     {
         AssertNotDisposed();
-        return ResolveLinkTargetImpl(ValidatePath(linkPath));
+        return TryResolveLinkTargetImpl(ValidatePath(linkPath), out resolvedPath);
     }
 
     /// <summary>
     /// Resolves the target of a symbolic link.
     /// </summary>
     /// <param name="linkPath">The path of the symbolic link to resolve.</param>
-    protected abstract UPath? ResolveLinkTargetImpl(UPath linkPath);
+    /// <param name="resolvedPath"></param>
+    protected abstract bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath);
 
     // ----------------------------------------------
     // Search API

diff --git a/src/Zio/FileSystems/MemoryFileSystem.cs b/src/Zio/FileSystems/MemoryFileSystem.cs
@@ -760,9 +760,10 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
     }
 
     /// <inheritdoc />
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
-        return null;
+        resolvedPath = default;
+        return false;
     }
 
     // ----------------------------------------------

diff --git a/src/Zio/FileSystems/MountFileSystem.cs b/src/Zio/FileSystems/MountFileSystem.cs
@@ -566,12 +566,24 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
     }
 
     /// <inheritdoc />
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
         var mountfs = TryGetMountOrNext(ref linkPath, out var mountPath);
-        var path = mountfs?.ResolveLinkTarget(linkPath);
 
-        return path != null ? CombinePrefix(mountPath, path.Value) : default(UPath?);
+        if (mountfs is null)
+        {
+            resolvedPath = default;
+            return false;
+        }
+
+        if (!mountfs.TryResolveLinkTarget(linkPath, out var resolved))
+        {
+            resolvedPath = default;
+            return false;
+        }
+
+        resolvedPath = CombinePrefix(mountPath, resolved);
+        return true;
     }
 
     /// <inheritdoc />

diff --git a/src/Zio/FileSystems/PhysicalFileSystem.cs b/src/Zio/FileSystems/PhysicalFileSystem.cs
@@ -516,7 +516,7 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
     }
 
     /// <inheritdoc />
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
         if (IsWithinSpecialDirectory(linkPath))
         {
@@ -536,7 +536,8 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
         }
         else
         {
-            return null;
+            resolvedPath = default;
+            return false;
         }
 
 #if NET7_0_OR_GREATER
@@ -545,7 +546,14 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
         var systemResult = IsOnWindows ? Interop.Windows.GetFinalPathName(systemPath) : Interop.Unix.readlink(systemPath);
 #endif
 
-        return systemResult != null ? ConvertPathFromInternal(systemResult) : default(UPath?);
+        if (systemResult == null)
+        {
+            resolvedPath = default;
+            return false;
+        }
+
+        resolvedPath = ConvertPathFromInternal(systemResult);
+        return true;
     }
 
     // ----------------------------------------------

diff --git a/src/Zio/FileSystems/ZipArchiveFileSystem.cs b/src/Zio/FileSystems/ZipArchiveFileSystem.cs
@@ -824,9 +824,10 @@ protected override void CreateSymbolicLinkImpl(UPath path, UPath pathToTarget)
     }
 
     /// <inheritdoc />
-    protected override UPath? ResolveLinkTargetImpl(UPath linkPath)
+    protected override bool TryResolveLinkTargetImpl(UPath linkPath, out UPath resolvedPath)
     {
-        return null;
+        resolvedPath = UPath.Empty;
+        return false;
     }
 
     /// <inheritdoc />

diff --git a/src/Zio/IFileSystem.cs b/src/Zio/IFileSystem.cs
@@ -174,7 +174,8 @@ public interface IFileSystem : IDisposable
     /// Resolves the target of a symbolic link.
     /// </summary>
     /// <param name="linkPath">The path of the symbolic link to resolve.</param>
-    UPath? ResolveLinkTarget(UPath linkPath);
+    /// <param name="resolvedPath">The path of the symbolic link resolved if true is returned.</param>
+    bool TryResolveLinkTarget(UPath linkPath, out UPath resolvedPath);
 
     // ----------------------------------------------
     // Search API