From 64a45d6a226fe7963cc5aae4318a409882205a24 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20=C4=8Capek?= <jan.capek@braiins.cz>
Date: Mon, 17 Sep 2018 12:17:05 +0200
Subject: [PATCH 1/2] Add test case demonstrating broken bit positions for
 integers > 1 byte

There are 2 issues with this:

- the BitIntsLsb struct is serialized in Msb-first order
- val1 and val2 serialization is also broken
---
 .../tests/packing_bit_positioning.rs          | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/packed_struct_tests/tests/packing_bit_positioning.rs b/packed_struct_tests/tests/packing_bit_positioning.rs
index 766cf82..06f3b7f 100644
--- a/packed_struct_tests/tests/packing_bit_positioning.rs
+++ b/packed_struct_tests/tests/packing_bit_positioning.rs
@@ -60,6 +60,32 @@ fn test_packing_bit_positions_lsb() {
 }
 
 
+#[derive(PackedStruct, PartialEq, Debug)]
+#[packed_struct(size_bytes="4", bit_numbering="lsb0", endian="lsb")]
+pub struct BigIntsLsb {
+    #[packed_field(bits="2:0")]
+    pub val1: Integer<u8, packed_bits::Bits3>,
+    #[packed_field(bits="6")]
+    pub val2: bool,
+    #[packed_field(bits="31:16")]
+    pub val3: Integer<u16, packed_bits::Bits16>,
+}
+
+#[test]
+fn test_packing_bit_positions_bigints_lsb() {
+    let a = BigIntsLsb {
+        val1: 7.into(),
+        val2: true,
+        val3: 0xbeef.into(),
+    };
+
+    let packed = a.pack();
+    assert_eq!(&[0x07u8, 0x04, 0xef, 0xbe], &packed);
+
+    let unpacked = BigIntsLsb::unpack(&packed).unwrap();
+    assert_eq!(a, unpacked);
+}
+
 
 #[test]
 fn test_packing_byte_position() {

From 46f5fa1b645bcbc2be487bbd3fd5af1039ebbe97 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20=C4=8Capek?= <jan.capek@braiins.cz>
Date: Thu, 27 Sep 2018 21:04:49 +0200
Subject: [PATCH 2/2] Change lsb0 bit allocations to make it fit the desired
 LSB endianness.

---
 packed_struct_tests/tests/packing_bit_positioning.rs | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/packed_struct_tests/tests/packing_bit_positioning.rs b/packed_struct_tests/tests/packing_bit_positioning.rs
index 06f3b7f..8245943 100644
--- a/packed_struct_tests/tests/packing_bit_positioning.rs
+++ b/packed_struct_tests/tests/packing_bit_positioning.rs
@@ -63,15 +63,16 @@ fn test_packing_bit_positions_lsb() {
 #[derive(PackedStruct, PartialEq, Debug)]
 #[packed_struct(size_bytes="4", bit_numbering="lsb0", endian="lsb")]
 pub struct BigIntsLsb {
-    #[packed_field(bits="2:0")]
+    #[packed_field(bits="26:24")]
     pub val1: Integer<u8, packed_bits::Bits3>,
-    #[packed_field(bits="6")]
+    #[packed_field(bits="18")]
     pub val2: bool,
-    #[packed_field(bits="31:16")]
+    #[packed_field(bits="15:0")]
     pub val3: Integer<u16, packed_bits::Bits16>,
 }
 
 #[test]
+/// This test should verify the packing/unpacking a hypothetical 32-bit register that contains 0xbeef0407
 fn test_packing_bit_positions_bigints_lsb() {
     let a = BigIntsLsb {
         val1: 7.into(),
@@ -80,7 +81,7 @@ fn test_packing_bit_positions_bigints_lsb() {
     };
 
     let packed = a.pack();
-    assert_eq!(&[0x07u8, 0x04, 0xef, 0xbe], &packed);
+    assert_eq!(&[0x07u8, 0x04, 0xef, 0xbe], &packed, "mismatch received: {}", a);
 
     let unpacked = BigIntsLsb::unpack(&packed).unwrap();
     assert_eq!(a, unpacked);