Fixed temporary folder detection on MacOS

CHANGELOG.md

@@ -33,6 +33,9 @@
 * Fixed UB when freeing strings received from JS if not using the default allocator.
   [#3808](https://github.com/rustwasm/wasm-bindgen/pull/3808)
 
+* Fixed temporary folder detection by `wasm-bindgen-test-runner` on MacOS.
+  [#3816](https://github.com/rustwasm/wasm-bindgen/pull/3816)
+
 ## [0.2.90](https://github.com/rustwasm/wasm-bindgen/compare/0.2.89...0.2.90)
 
 Released 2024-01-06

crates/cli/src/bin/wasm-bindgen-test-runner/main.rs

@@ -88,10 +88,10 @@ fn main() -> anyhow::Result<()> {
     // - a tmp directory, generated by rustdoc
     // we would like a directory we have write access to. if we assume cargo-like directories,
     // we end up with the path `/wbg-out`
-    let tmpdir = if wasm_file_to_test
-        .to_string_lossy()
-        .starts_with("/tmp/rustdoc")
-    {
+    let tmpdir = if {
+        let file = wasm_file_to_test.to_string_lossy();
+        file.starts_with("/tmp/rustdoc") || file.starts_with("/var/folders")
+    } {
         wasm_file_to_test.parent() // chop off the file name and give us the /tmp/rustdoc<hash> directory
     } else {
         wasm_file_to_test