From f76d8dd654e459fa539da9b2fc6c445af8d75443 Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Thu, 23 Nov 2023 16:37:41 +0100
Subject: [PATCH 1/2] Move int.toF() function into io module

---
 poseidon2.nim                       | 1 +
 poseidon2/io.nim                    | 7 +++++++
 poseidon2/types.nim                 | 6 ------
 tests/poseidon2/testCompress.nim    | 2 +-
 tests/poseidon2/testPermutation.nim | 2 +-
 tests/poseidon2/testSponge.nim      | 1 +
 6 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/poseidon2.nim b/poseidon2.nim
index f071913..7959392 100644
--- a/poseidon2.nim
+++ b/poseidon2.nim
@@ -8,5 +8,6 @@ export sponge
 export compress
 export merkle
 export toBytes
+export toF
 export elements
 export types
diff --git a/poseidon2/io.nim b/poseidon2/io.nim
index 822c035..d5b44e1 100644
--- a/poseidon2/io.nim
+++ b/poseidon2/io.nim
@@ -1,6 +1,7 @@
 import ./types
 import constantine/math/arithmetic
 import constantine/math/io/io_bigints
+import constantine/math/io/io_fields
 import constantine/math/config/curves
 
 export curves
@@ -35,3 +36,9 @@ iterator elements*(bytes: openArray[byte], _: type F): F =
   let finalChunk = bytes[chunkStart..<bytes.len] & endMarker
   let finalElement = F.fromOpenArray(finalChunk)
   yield finalElement
+
+# Remark: since `fromInt()` does not work at compile time, this doesn't either
+func toF*(a: int) : F =
+  var y : F
+  y.fromInt(a)
+  return y
diff --git a/poseidon2/types.nim b/poseidon2/types.nim
index ba72715..5cc931c 100644
--- a/poseidon2/types.nim
+++ b/poseidon2/types.nim
@@ -18,12 +18,6 @@ func getZero*() : F =
   setZero(z)
   return z
 
-# Remark: since `fromInt()` does not work at compile time, this doesn't either
-func toF*(a: int) : F =
-  var y : F
-  y.fromInt(a)
-  return y
-
 #-------------------------------------------------------------------------------
 
 const zero* : F = getZero()
diff --git a/tests/poseidon2/testCompress.nim b/tests/poseidon2/testCompress.nim
index 9f51492..8b0a415 100644
--- a/tests/poseidon2/testCompress.nim
+++ b/tests/poseidon2/testCompress.nim
@@ -1,6 +1,6 @@
 import std/unittest
 import constantine/math/arithmetic
-import poseidon2/types
+import poseidon2/io
 import poseidon2/permutation
 import poseidon2/compress
 
diff --git a/tests/poseidon2/testPermutation.nim b/tests/poseidon2/testPermutation.nim
index 7d34100..b8239fb 100644
--- a/tests/poseidon2/testPermutation.nim
+++ b/tests/poseidon2/testPermutation.nim
@@ -3,9 +3,9 @@ import std/unittest
 import constantine/math/arithmetic
 import constantine/math/io/io_fields
 import constantine/math/io/io_bigints
-import constantine/math/config/curves
 
 import poseidon2/types
+import poseidon2/io
 import poseidon2/permutation
 
 suite "permutation":
diff --git a/tests/poseidon2/testSponge.nim b/tests/poseidon2/testSponge.nim
index 37e58a6..edd931a 100644
--- a/tests/poseidon2/testSponge.nim
+++ b/tests/poseidon2/testSponge.nim
@@ -5,6 +5,7 @@ import constantine/math/io/io_fields
 import constantine/math/arithmetic
 
 import poseidon2/types
+import poseidon2/io
 import poseidon2
 
 #-------------------------------------------------------------------------------

From ddff11d4f02a3d53c026ab5ae8571da193211b17 Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Thu, 23 Nov 2023 17:07:17 +0100
Subject: [PATCH 2/2] Convert all types of integers to field element

---
 poseidon2/io.nim           |  9 +++++----
 tests/poseidon2/testIo.nim | 27 +++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/poseidon2/io.nim b/poseidon2/io.nim
index d5b44e1..2c8dd6b 100644
--- a/poseidon2/io.nim
+++ b/poseidon2/io.nim
@@ -38,7 +38,8 @@ iterator elements*(bytes: openArray[byte], _: type F): F =
   yield finalElement
 
 # Remark: since `fromInt()` does not work at compile time, this doesn't either
-func toF*(a: int) : F =
-  var y : F
-  y.fromInt(a)
-  return y
+func toF*(a: SomeInteger | SomeUnsignedInt) : F =
+  when a is SomeInteger:
+    fromInt(result, a)
+  else:
+    fromUInt(result, a)
diff --git a/tests/poseidon2/testIo.nim b/tests/poseidon2/testIo.nim
index 97be438..23b1ce9 100644
--- a/tests/poseidon2/testIo.nim
+++ b/tests/poseidon2/testIo.nim
@@ -1,6 +1,7 @@
 import std/unittest
 import std/sequtils
 import constantine/math/io/io_bigints
+import constantine/math/io/io_fields
 import constantine/math/arithmetic
 import poseidon2/types
 import poseidon2/io
@@ -54,3 +55,29 @@ suite "conversion to/from bytes":
     var expected: array[32, byte]
     marshal(expected, element.toBig(), littleEndian)
     check element.toBytes() == expected
+
+suite "conversion from integers":
+
+  test "converts unsigned integers to a field element":
+
+    proc checkConversion[I](integer: I) =
+      var expected: F
+      fromUint(expected, integer)
+      check bool(integer.toF == expected)
+
+    checkConversion(0x11'u8)
+    checkConversion(0x1122'u16)
+    checkConversion(0x11223344'u32)
+    checkConversion(0x1122334455667788'u64)
+
+  test "converts signed integers to a field element":
+
+    proc checkConversion[I](integer: I) =
+      var expected: F
+      fromInt(expected, integer)
+      check bool(integer.toF == expected)
+
+    checkConversion(0x11'i8)
+    checkConversion(0x1122'i16)
+    checkConversion(0x11223344'i32)
+    checkConversion(0x1122334455667788'i64)