diff --git a/tests/test.rs b/tests/test.rs
index 34ba6a8..0e9bdd2 100644
--- a/tests/test.rs
+++ b/tests/test.rs
@@ -1,4 +1,84 @@
+use byteorder::{ReadBytesExt, WriteBytesExt};
 use paste::paste;
+use std::io::{self, Cursor, Read, Seek, SeekFrom};
+
+/// A reader that tracks how many times bytes in the inner reader been read. Useful to check read coverage.
+#[derive(Debug)]
+pub struct ReadCounter<T> {
+    inner: T,
+    reads: io::Cursor<Vec<u8>>,
+}
+
+impl<T> ReadCounter<T> {
+    pub fn new(inner: T) -> Self {
+        ReadCounter {
+            inner,
+            reads: Cursor::new(vec![]),
+        }
+    }
+    pub fn new_size(inner: T, size: usize) -> Self {
+        ReadCounter {
+            inner,
+            reads: Cursor::new(vec![0; size]),
+        }
+    }
+    pub fn into_reads(self) -> Vec<u8> {
+        self.reads.into_inner()
+    }
+}
+
+impl<T> Seek for ReadCounter<T>
+where
+    T: Seek,
+{
+    fn seek(&mut self, style: SeekFrom) -> io::Result<u64> {
+        self.reads.seek(style).unwrap();
+        self.inner.seek(style)
+    }
+}
+
+impl<T> Read for ReadCounter<T>
+where
+    T: Read,
+{
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        let read = self.inner.read(buf);
+        if let Ok(read) = read {
+            for _ in 0..read {
+                let r = match self.reads.read_u8() {
+                    Ok(r) => {
+                        self.reads.seek(SeekFrom::Current(-1)).unwrap();
+                        Ok(r)
+                    }
+                    Err(ref e) if e.kind() == io::ErrorKind::UnexpectedEof => Ok(0),
+                    Err(e) => Err(e),
+                }
+                .unwrap();
+                self.reads.write_u8(r + 1).unwrap();
+            }
+        }
+        read
+    }
+}
+
+mod test {
+    #[test]
+    fn test_read_counter() {
+        use byteorder::{ReadBytesExt, LE};
+        use std::io::{Cursor, Seek, SeekFrom};
+
+        let source = Cursor::new(vec![1, 2, 3, 4, 5, 6, 7, 8, 9]);
+        let mut proxy = super::ReadCounter::new(source);
+
+        proxy.seek(SeekFrom::Start(3)).unwrap();
+        proxy.read_u8().unwrap();
+        proxy.seek(SeekFrom::Current(-1)).unwrap();
+        proxy.read_u8().unwrap();
+        proxy.read_u16::<LE>().unwrap();
+
+        assert_eq!(proxy.reads.into_inner(), vec![0, 0, 0, 2, 1, 1]);
+    }
+}
 
 static AES_KEY: &str = "lNJbw660IOC+kU7cnVQ1oeqrXyhk4J6UAZrCBbcnp94=";
 
@@ -35,10 +115,16 @@ macro_rules! encryptindex {
                                 .and_then(|bytes| {
                                     aes::Aes256Dec::new_from_slice(bytes).map_err(|_| unpak::Error::Aes)
                                 }).unwrap();
+
+
+                    let mut inner_reader = std::io::Cursor::new(include_bytes!(concat!("packs/pack_", $version, $compress, $encrypt, $encryptindex, ".pak")));
+                    let len = inner_reader.seek(SeekFrom::End(0)).unwrap();
+
                     let mut pak = unpak::PakReader::new_any(
-                        std::io::Cursor::new(include_bytes!(concat!("packs/pack_", $version, $compress, $encrypt, $encryptindex, ".pak"))),
+                        ReadCounter::new_size(inner_reader, len as usize),
                         Some(key),
                     ).unwrap();
+
                     assert_eq!(pak.mount_point(), "../mount/point/root/");
                     assert_eq!(pak.version(), $exp_version);
                     use std::collections::HashSet;
@@ -57,6 +143,13 @@ macro_rules! encryptindex {
                             name => panic!("unrecognized file {}", name)
                         }
                     }
+
+                    for r in pak.into_reader().into_reads() {
+                        // sanity check. a pak file can be constructed with a lot of dead space
+                        // which wouldn't have to be read, but so far all bytes in paks generated
+                        // by UnrealPak are meaningful
+                        assert!(r > 0, "every byte has been read at least once");
+                    }
                 }
             }
         )*