better test error messages

2 files changed, 18 insertions, 2 deletions

diff --git a/tests/fixtures/mod.rs b/tests/fixtures/mod.rs
index ef5a742..08f09c1 100644
--- a/tests/fixtures/mod.rs
+++ b/tests/fixtures/mod.rs
@@ -99,6 +99,7 @@ impl BuiltFixture {
 }
 
 #[allow(dead_code)]
+#[track_caller]
 pub fn read(f: &mut std::fs::File) -> Vec<u8> {
     assert!(read_ready(f.as_raw_fd()));
     let mut buf = vec![0u8; 1024];
@@ -108,6 +109,7 @@ pub fn read(f: &mut std::fs::File) -> Vec<u8> {
 }
 
 #[allow(dead_code)]
+#[track_caller]
 pub fn read_line(f: &mut std::io::BufReader<&mut std::fs::File>) -> Vec<u8> {
     assert!(!f.buffer().is_empty() || read_ready(f.get_ref().as_raw_fd()));
     let mut buf = vec![];
diff --git a/tests/input.rs b/tests/input.rs
index b2a8b28..033499f 100644
--- a/tests/input.rs
+++ b/tests/input.rs
@@ -198,14 +198,17 @@ fn run_input_test(
     });
 }
 
+#[track_caller]
 fn write(f: &mut std::fs::File, key: textmode::Key) {
     f.write_all(&key.into_bytes()).unwrap();
 }
 
+#[track_caller]
 fn read(f: &mut std::io::BufReader<&mut std::fs::File>) -> String {
     std::string::String::from_utf8(fixtures::read_line(f)).unwrap()
 }
 
+#[track_caller]
 fn assert_line(
     f: &mut std::io::BufReader<&mut std::fs::File>,
     expected: &str,
@@ -213,7 +216,18 @@ fn assert_line(
     assert_eq!(read(f), format!("{}\r\n", expected));
 }
 
+#[track_caller]
 fn assert_no_more_lines(f: &mut std::io::BufReader<&mut std::fs::File>) {
-    assert!(!fixtures::read_ready(f.get_ref().as_raw_fd()));
-    assert!(f.buffer().is_empty());
+    if fixtures::read_ready(f.get_ref().as_raw_fd()) || !f.buffer().is_empty()
+    {
+        use std::io::Read as _;
+        let mut buf = vec![0; 4096];
+        let bytes = f.read(&mut buf).unwrap();
+        buf.truncate(bytes);
+        panic!(
+            "got bytes: \"{}\"({:?})",
+            std::string::String::from_utf8_lossy(&buf),
+            buf
+        );
+    }
 }