test: Add tests for Cursor BufRead past end behavior
What the developer wrote
Authored by jrakibi
test: Add tests for Cursor BufRead past end behavior
Add tests to verify BufRead Cursor behavior matches std
What changed, and why it matters
This commit only adds two new unit tests to the project's custom I/O library. The tests check that a Cursor (a simple in-memory reader) behaves the same way as Rust's standard library when asked to read past the end of its data: it should return an empty buffer and allow the position to advance without error. There is no code change that fixes or changes behavior, and nothing here indicates a security issue.
No action required. This is a test-only commit with no security relevance.
Security signals we found
No strong security signals were identified.
Evidence from the diff
The diff adds tests in io/src/lib.rs verifying that Cursor::fill_buf() returns an empty slice and that Cursor::consume() advances position beyond the buffer length when the cursor position is already past the end of the underlying data. This is purely a test addition; no implementation code is modified. The behavior being tested is consistent with std::io::Cursor semantics.
Changed components
io/src/lib.rs testsInspect captured patch +20 / −0
diff --git a/io/src/lib.rs b/io/src/lib.rs
index 6e287150..dcd463b5 100644
--- a/io/src/lib.rs
+++ b/io/src/lib.rs
@@ -517,4 +517,24 @@ mod tests {
assert_eq!(read, 32);
assert_eq!(data[0..32], v[0..32]);
}
+
+ #[test]
+ fn cursor_fill_buf_past_end() {
+ let data = [1, 2, 3];
+ let mut cursor = Cursor::new(&data);
+ cursor.set_position(10);
+
+ let buf = cursor.fill_buf().unwrap();
+ assert!(buf.is_empty());
+ }
+
+ #[test]
+ fn cursor_consume_past_end() {
+ let data = [1, 2, 3];
+ let mut cursor = Cursor::new(&data);
+ cursor.set_position(10);
+
+ cursor.consume(5);
+ assert_eq!(cursor.position(), 15);
+ }
}
Why this scored 15/100
Community notes
Notes can correct, qualify, or add evidence to the AI analysis. Every note shown here has been validated by a human moderator.
The AI analysis stands alone for now. Submit a note if you can add evidence or important context.