diff --git a/Tests/TaggedNodeCorpusRoundTripTests.swift b/Tests/TaggedNodeCorpusRoundTripTests.swift
index 6fea503..4aca297 100644
--- a/Tests/TaggedNodeCorpusRoundTripTests.swift
+++ b/Tests/TaggedNodeCorpusRoundTripTests.swift
@@ -20,19 +20,17 @@ struct TaggedNodeCorpusRoundTripTests {
         var accepted = 0
         var rejected = 0
         // `URL.lastPathComponent` is `String` on Darwin's Foundation but `String?` on this
-        // toolchain's swift-corelibs-foundation. A cast or function call INSIDE the `sorted(by:)`
-        // trailing closure itself (tried first: an `as String?` coercion, then a named helper)
-        // sent this toolchain's overload resolution down a path that inferred the closure's
-        // parameters as `NSURL` instead of `URL`, breaking every other `URL`-typed use below --
-        // even though a bare `$0.lastPathComponent < $1.lastPathComponent` comparison (no cast, no
-        // call) resolved fine. Precomputing the sort key in a separate `map` keeps the `sorted(by:)`
-        // closure itself exactly that simple (comparing two already-plain `String`s), sidestepping
-        // whatever in the trailing closure was confusing the resolver.
-        let sortedURLs = urls
-            .map { url in (url: url, name: (url.lastPathComponent as String?) ?? "") }
-            .sorted { $0.name < $1.name }
-            .map(\.url)
-        for url in sortedURLs {
+        // toolchain's swift-corelibs-foundation. Every attempt to derive a `[URL]` THROUGH a
+        // `map`/`sorted` chain touching `.lastPathComponent` -- an inline cast, a named helper, a
+        // tuple-and-keypath precompute -- came back from the Linux relay with `url` re-inferred as
+        // `NSURL` somewhere downstream, breaking `String(contentsOf:encoding:)`. Sorting the plain
+        // `Int` INDICES instead keeps every `.sorted(by:)`/`.map` in this file entirely divorced
+        // from any URL-typed value; `urls[index]` below is the one and only place a `URL` from the
+        // original, never-transformed array is touched, so its type can never drift.
+        let names = urls.map { ($0.lastPathComponent as String?) ?? "" }
+        let order = names.indices.sorted { names[$0] < names[$1] }
+        for index in order {
+            let url = urls[index]
             let source = try String(contentsOf: url, encoding: .utf8)
             let parsed: PureYAML.Tagged.Node
             do {