test: test listing more than 4096 bytes of extended attributes

fixes #84

Author: Stebalien

tests/main.rs

@@ -2,7 +2,7 @@ use std::collections::BTreeSet;
 use std::ffi::OsStr;
 use xattr::FileExt;
 
-use tempfile::{tempfile, NamedTempFile};
+use tempfile::{tempfile, tempfile_in, NamedTempFile};
 
 #[test]
 #[cfg(any(
@@ -171,6 +171,37 @@ fn test_multi() {
     assert!(items.is_empty());
 }
 
+// This test is skipped on android because the /data/tmp filesystem doesn't support >4kib of
+// extended attributes.
+#[test]
+#[cfg(any(target_os = "linux", target_os = "freebsd", target_os = "macos"))]
+fn test_large() {
+    use std::ffi::OsString;
+    use std::os::unix::ffi::OsStrExt;
+    // On Linux, this only works in tmpfs!
+    let tmp = if cfg!(target_os = "linux") {
+        tempfile_in("/dev/shm")
+    } else {
+        tempfile()
+    }
+    .unwrap();
+    let mut items: BTreeSet<OsString> = (0..100)
+        .map(|i| format!("user.test{i:0100}").into())
+        .collect();
+
+    for it in &items {
+        tmp.set_xattr(it, b"value").unwrap();
+    }
+    for it in tmp
+        .list_xattr()
+        .unwrap()
+        .filter(|x| x.as_bytes().starts_with(b"user."))
+    {
+        assert!(items.remove(&*it));
+    }
+    assert!(items.is_empty());
+}
+
 // Tests the deref API variants - regression test for
 // https://github.com/Stebalien/xattr/issues/57
 #[test]