Skip to content

[patch] Keep ".." segments that climb above the start in RelativeDirectoryPath.Normalize #380

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
matt-edmondson merged 1 commit into from
Oct 6, 2026
Merged

[patch] Keep ".." segments that climb above the start in RelativeDirectoryPath.Normalize #380

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
36 changes: 21 additions & 15 deletions Semantics.Paths/Implementations/RelativeDirectoryPath.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2,11 +2,9 @@

namespace ktsu.Semantics.Paths;

using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.IO;
#if !NET5_0_OR_GREATER
using System.Runtime.InteropServices;
#endif

/// <summary>
/// Represents a relative directory path
Expand Down Expand Up @@ -209,18 +207,26 @@ public RelativeDirectoryPath AsRelative(AbsoluteDirectoryPath baseDirectory)
return this;
}

// Use Path.GetFullPath with a dummy base to normalize relative paths
#if NET5_0_OR_GREATER
string dummyBase = OperatingSystem.IsWindows() ? "C:\\" : "/";
#else
string dummyBase = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? "C:\\" : "/";
#endif
string fullPath = Path.GetFullPath(Path.Combine(dummyBase, path));
#if NETSTANDARD2_0
string normalized = PathPolyfill.GetRelativePath(dummyBase, fullPath);
#else
string normalized = Path.GetRelativePath(dummyBase, fullPath);
#endif
// Resolve segments lexically. Resolving against a dummy root would discard every ".." that
// climbs above the starting point, changing which directory the path names.
List<string> segments = [];
foreach (string segment in path.Split(['/', '\\'], StringSplitOptions.RemoveEmptyEntries))
{
if (segment == ".")
{
continue;
}

if (segment == ".." && segments.Count > 0 && segments[^1] != "..")
{
segments.RemoveAt(segments.Count - 1);
continue;
}

segments.Add(segment);
}

string normalized = segments.Count == 0 ? "." : string.Join(Path.DirectorySeparatorChar.ToString(), segments);

return Create<RelativeDirectoryPath>(normalized);
}
Expand Down
18 changes: 16 additions & 2 deletions Semantics.Test/Paths/PathUtilityTests.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -178,8 +178,22 @@ public void Normalize_WithOnlyDots_ResolvesCorrectly()

RelativeDirectoryPath normalized = dotPath.Normalize();

Assert.IsNotNull(normalized);
Assert.Contains("folder", normalized.WeakString);
Assert.AreEqual(TestPaths.Relative("..", "folder"), normalized.WeakString);
}

[TestMethod]
[DataRow(new[] { "..", "sibling" }, new[] { "..", "sibling" })]
[DataRow(new[] { "a", "..", "..", "b" }, new[] { "..", "b" })]
[DataRow(new[] { "..", "..", "x", "y" }, new[] { "..", "..", "x", "y" })]
[DataRow(new[] { "a", ".", "b", "..", "c" }, new[] { "a", "c" })]
[DataRow(new[] { "a", ".." }, new[] { "." })]
public void Normalize_KeepsParentSegmentsThatClimbAboveTheStart(string[] input, string[] expected)
{
RelativeDirectoryPath path = RelativeDirectoryPath.Create<RelativeDirectoryPath>(TestPaths.Relative(input));

RelativeDirectoryPath normalized = path.Normalize();

Assert.AreEqual(TestPaths.Relative(expected), normalized.WeakString);
}

[TestMethod]
Expand Down
Loading