handle relative paths with too many ".."

lib/std/fs/test.zig

@@ -95,8 +95,8 @@ test "openDirAbsolute" {
 test "openDir cwd parent .." {
     if (builtin.os.tag == .wasi) return error.SkipZigTest;
 
-    var cwd = try fs.cwd().openDir("..", .{});
-    defer cwd.close();
+    var dir = try fs.cwd().openDir("..", .{});
+    defer dir.close();
 }
 
 test "readLinkAbsolute" {

lib/std/mem.zig

@@ -2151,7 +2151,7 @@ pub fn collapseRepeats(comptime T: type, slice: []T, elem: T) []T {
 fn testCollapseRepeats(str: []const u8, elem: u8, expected: []const u8) !void {
     const mutable = try std.testing.allocator.dupe(u8, str);
     defer std.testing.allocator.free(mutable);
-    testing.expect(std.mem.eql(u8, collapseRepeats(u8, mutable, elem), expected));
+    try testing.expect(std.mem.eql(u8, collapseRepeats(u8, mutable, elem), expected));
 }
 test "collapseRepeats" {
     try testCollapseRepeats("", '/', "");

lib/std/os/windows.zig

@@ -1817,20 +1817,42 @@ pub fn sliceToPrefixedFileW(s: []const u8) !PathSpace {
             else => {},
         }
     }
+    const prefix_u16 = [_]u16{ '\\', '?', '?', '\\' };
     const start_index = if (prefix_index > 0 or !std.fs.path.isAbsolute(s)) 0 else blk: {
-        const prefix_u16 = [_]u16{ '\\', '?', '?', '\\' };
         mem.copy(u16, path_space.data[0..], prefix_u16[0..]);
         break :blk prefix_u16.len;
     };
     path_space.len = start_index + try std.unicode.utf8ToUtf16Le(path_space.data[start_index..], s);
     if (path_space.len > path_space.data.len) return error.NameTooLong;
     path_space.len = start_index + (normalizePath(u16, path_space.data[start_index..path_space.len]) catch |err| switch (err) {
-        error.TooManyParentDirs => return error.BadPathName,
+        error.TooManyParentDirs => {
+            if (!std.fs.path.isAbsolute(s)) {
+                var temp_path: PathSpace = undefined;
+                temp_path.len = try std.unicode.utf8ToUtf16Le(&temp_path.data, s);
+                std.debug.assert(temp_path.len == path_space.len);
+                temp_path.data[path_space.len] = 0;
+                path_space.len = prefix_u16.len + try getFullPathNameW(&temp_path.data, path_space.data[prefix_u16.len..]);
+                mem.copy(u16, &path_space.data, &prefix_u16);
+                std.debug.assert(path_space.data[path_space.len] == 0);
+                return path_space;
+            }
+            return error.BadPathName;
+        },
     });
     path_space.data[path_space.len] = 0;
     return path_space;
 }
 
+fn getFullPathNameW(path: [*:0]const u16, out: []u16) !usize {
+    const result= kernel32.GetFullPathNameW(path, @intCast(u32, out.len), std.meta.assumeSentinel(out.ptr, 0), null);
+    if (result == 0) {
+        switch (kernel32.GetLastError()) {
+            else => |err| return unexpectedError(err),
+        }
+    }
+    return result;
+}
+
 /// Assumes an absolute path.
 pub fn wToPrefixedFileW(s: []const u16) !PathSpace {
     // TODO https://github.com/ziglang/zig/issues/2765

lib/std/os/windows/kernel32.zig

@@ -136,6 +136,13 @@ pub extern "kernel32" fn GetFinalPathNameByHandleW(
     dwFlags: DWORD,
 ) callconv(WINAPI) DWORD;
 
+pub extern "kernel32" fn GetFullPathNameW(
+    lpFileName: [*:0]const u16,
+    nBufferLength: u32,
+    lpBuffer: ?[*:0]u16,
+    lpFilePart: ?*?[*:0]u16,
+) callconv(@import("std").os.windows.WINAPI) u32;
+
 pub extern "kernel32" fn GetOverlappedResult(hFile: HANDLE, lpOverlapped: *OVERLAPPED, lpNumberOfBytesTransferred: *DWORD, bWait: BOOL) callconv(WINAPI) BOOL;
 
 pub extern "kernel32" fn GetProcessHeap() callconv(WINAPI) ?HANDLE;

lib/std/os/windows/test.zig

@@ -14,12 +14,12 @@ fn testRemoveDotDirs(str: []const u8, expected: []const u8) !void {
     const mutable = try testing.allocator.dupe(u8, str);
     defer testing.allocator.free(mutable);
     const actual = mutable[0..try windows.removeDotDirsSanitized(u8, mutable)];
-    testing.expect(mem.eql(u8, actual, expected));
+    try testing.expect(mem.eql(u8, actual, expected));
 }
 fn testRemoveDotDirsError(err: anyerror, str: []const u8) !void {
     const mutable = try testing.allocator.dupe(u8, str);
     defer testing.allocator.free(mutable);
-    testing.expectError(err, windows.removeDotDirsSanitized(u8, mutable));
+    try testing.expectError(err, windows.removeDotDirsSanitized(u8, mutable));
 }
 test "removeDotDirs" {
     try testRemoveDotDirs("", "");