Moves the hex operations to our own functions

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip44Encryption/crypto/XChaCha20Test.kt

@@ -20,12 +20,13 @@
  */
 package com.vitorpamplona.quartz.nip44Encryption.crypto
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
 import kotlin.test.Test
 import kotlin.test.assertContentEquals
 
 /** Test vectors from libsodium xchacha20.c */
 class XChaCha20Test {
-    private fun hex(s: String): ByteArray = s.chunked(2).map { it.toInt(16).toByte() }.toByteArray()
+    private fun hex(s: String): ByteArray = s.hexToByteArray()
 
     // HChaCha20 test vectors from libsodium
     data class HChaCha20TV(

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/FieldPTest.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNull
@@ -27,12 +29,9 @@ import kotlin.test.assertTrue
 
 /** Tests for field arithmetic modulo p. */
 class FieldPTest {
-    private fun hex(s: String) =
+    private fun hex(s: String) = U256.fromBytes(s.hexToByteArray())
-        U256.fromBytes(
-            s.chunked(2).map { it.toInt(16).toByte() }.toByteArray(),
-        )
 
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
     // ==================== Basic identities ====================
 

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/GlvTest.kt

@@ -20,18 +20,17 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertTrue
 
 /** Comprehensive tests for GLV endomorphism and wNAF encoding. */
 class GlvTest {
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
-    private fun hex(s: String) =
+    private fun hex(s: String) = U256.fromBytes(s.hexToByteArray())
-        U256.fromBytes(
-            s.chunked(2).map { it.toInt(16).toByte() }.toByteArray(),
-        )
 
     @Suppress("ktlint:standard:property-naming")
     private val LAMBDA = hex("5363ad4cc05c30e0a5261c028812645a122e22ea20816678df02967c1b23bd72")

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/KeyCodecTest.kt

@@ -20,6 +20,7 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -27,7 +28,7 @@ import kotlin.test.assertTrue
 
 /** Tests for KeyCodec: key parsing, serialization, liftX, hasEvenY. */
 class KeyCodecTest {
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
     // ==================== liftX ====================
 

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/PointTest.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -27,12 +29,9 @@ import kotlin.test.assertTrue
 
 /** Tests for elliptic curve point operations. */
 class PointTest {
-    private fun hex(s: String) =
+    private fun hex(s: String) = U256.fromBytes(s.hexToByteArray())
-        U256.fromBytes(
-            s.chunked(2).map { it.toInt(16).toByte() }.toByteArray(),
-        )
 
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
     // ==================== Generator point ====================
 
@@ -361,11 +360,7 @@ class PointTest {
 
     @Test
     fun parseCompressedOddY() {
-        val privKeyBytes =
+        val privKeyBytes = "65f039136f8da8d3e87b4818746b53318d5481e24b2673f162815144223a0b5a".hexToByteArray()
-            "65f039136f8da8d3e87b4818746b53318d5481e24b2673f162815144223a0b5a"
-                .chunked(2)
-                .map { it.toInt(16).toByte() }
-                .toByteArray()
         val pubkey = Secp256k1.pubkeyCreate(privKeyBytes)
         val compressed = Secp256k1.pubKeyCompress(pubkey)
         assertEquals(0x03.toByte(), compressed[0]) // Odd y → 03 prefix

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/ScalarNTest.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -27,12 +29,9 @@ import kotlin.test.assertTrue
 
 /** Tests for scalar arithmetic modulo n. */
 class ScalarNTest {
-    private fun hex(s: String) =
+    private fun hex(s: String) = U256.fromBytes(s.hexToByteArray())
-        U256.fromBytes(
-            s.chunked(2).map { it.toInt(16).toByte() }.toByteArray(),
-        )
 
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
     // ==================== isValid ====================
 

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/utils/secp256k1/U256Test.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.quartz.utils.secp256k1
 
+import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -27,12 +29,9 @@ import kotlin.test.assertTrue
 
 /** Tests for 256-bit unsigned integer arithmetic. */
 class U256Test {
-    private fun hex(s: String) =
+    private fun hex(s: String) = U256.fromBytes(s.hexToByteArray())
-        U256.fromBytes(
-            s.chunked(2).map { it.toInt(16).toByte() }.toByteArray(),
-        )
 
-    private fun toHex(a: LongArray) = U256.toBytes(a).joinToString("") { "%02x".format(it) }
+    private fun toHex(a: LongArray) = U256.toBytes(a).toHexKey()
 
     // ==================== isZero / cmp ====================
 
@@ -150,10 +149,10 @@ class U256Test {
     @Test
     fun bytesRoundTrip() {
         val hex = "67E56582298859DDAE725F972992A07C6C4FB9F62A8FFF58CE3CA926A1063530"
-        val bytes = hex.chunked(2).map { it.toInt(16).toByte() }.toByteArray()
+        val bytes = hex.hexToByteArray()
         val limbs = U256.fromBytes(bytes)
         val back = U256.toBytes(limbs)
-        assertEquals(hex.lowercase(), back.joinToString("") { "%02x".format(it) })
+        assertEquals(hex.lowercase(), back.toHexKey())
     }
 
     @Test