Merge #19660: refactor: Make HexStr take a span

0a8aa626dd69a357e1b798b07b64cf4177a464a3 refactor: Make HexStr take a span (Wladimir J. van der Laan)

Pull request description:

  Make `HexSt`r take a span of bytes, instead of an awkward pair of templated iterators. This simplifies most of the uses.

ACKs for top commit:
  elichai:
    Code review ACK 0a8aa626dd69a357e1b798b07b64cf4177a464a3
  hebasto:
    re-ACK 0a8aa626dd69a357e1b798b07b64cf4177a464a3
  jonatack:
    re-ACK 0a8aa626dd69a357e1b798b07b64cf4177a464a3

Tree-SHA512: 6e178ece5cbac62119c857a10299b1e85422938084c3f03063e17119a5129e0c28016e05a6fabaa4c271a7e0a37c7cd89fa47c435ee19b38a5acfe80d00de992

3 files changed, 11 insertions, 34 deletions

diff --git a/src/test/crypto_tests.cpp b/src/test/crypto_tests.cpp
index bf5c587774..b3cc8cefd9 100644
--- a/src/test/crypto_tests.cpp
+++ b/src/test/crypto_tests.cpp
@@ -183,7 +183,7 @@ static void TestHKDF_SHA256_32(const std::string &ikm_hex, const std::string &sa
     CHKDF_HMAC_SHA256_L32 hkdf32(initial_key_material.data(), initial_key_material.size(), salt_stringified);
     unsigned char out[32];
     hkdf32.Expand32(info_stringified, out);
-    BOOST_CHECK(HexStr(out, out + 32) == okm_check_hex);
+    BOOST_CHECK(HexStr(out) == okm_check_hex);
 }
 
 static std::string LongTestString()
diff --git a/src/test/settings_tests.cpp b/src/test/settings_tests.cpp
index 91e039416c..548fd020a6 100644
--- a/src/test/settings_tests.cpp
+++ b/src/test/settings_tests.cpp
@@ -241,7 +241,7 @@ BOOST_FIXTURE_TEST_CASE(Merge, MergeTestingSetup)
 
     unsigned char out_sha_bytes[CSHA256::OUTPUT_SIZE];
     out_sha.Finalize(out_sha_bytes);
-    std::string out_sha_hex = HexStr(std::begin(out_sha_bytes), std::end(out_sha_bytes));
+    std::string out_sha_hex = HexStr(out_sha_bytes);
 
     // If check below fails, should manually dump the results with:
     //
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 15a2c1e300..b49370c967 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -105,47 +105,24 @@ BOOST_AUTO_TEST_CASE(util_ParseHex)
 BOOST_AUTO_TEST_CASE(util_HexStr)
 {
     BOOST_CHECK_EQUAL(
-        HexStr(ParseHex_expected, ParseHex_expected + sizeof(ParseHex_expected)),
+        HexStr(ParseHex_expected),
         "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f");
 
     BOOST_CHECK_EQUAL(
-        HexStr(ParseHex_expected + sizeof(ParseHex_expected),
-               ParseHex_expected + sizeof(ParseHex_expected)),
+        HexStr(Span<const unsigned char>(
+               ParseHex_expected + sizeof(ParseHex_expected),
+               ParseHex_expected + sizeof(ParseHex_expected))),
         "");
 
     BOOST_CHECK_EQUAL(
-        HexStr(ParseHex_expected, ParseHex_expected),
+        HexStr(Span<const unsigned char>(ParseHex_expected, ParseHex_expected)),
         "");
 
     std::vector<unsigned char> ParseHex_vec(ParseHex_expected, ParseHex_expected + 5);
 
     BOOST_CHECK_EQUAL(
-        HexStr(ParseHex_vec.rbegin(), ParseHex_vec.rend()),
-        "b0fd8a6704"
-    );
-
-    BOOST_CHECK_EQUAL(
-        HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected),
-               std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
-        ""
-    );
-
-    BOOST_CHECK_EQUAL(
-        HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 1),
-               std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
-        "04"
-    );
-
-    BOOST_CHECK_EQUAL(
-        HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 5),
-               std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
-        "b0fd8a6704"
-    );
-
-    BOOST_CHECK_EQUAL(
-        HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 65),
-               std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
-        "5f1df16b2b704c8a578d0bbaf74d385cde12c11ee50455f3c438ef4c3fbcf649b6de611feae06279a60939e028a8d65c10b73071a6f16719274855feb0fd8a6704"
+        HexStr(ParseHex_vec),
+        "04678afdb0"
     );
 }
 
@@ -1022,7 +999,7 @@ BOOST_FIXTURE_TEST_CASE(util_ArgsMerge, ArgsMergeTestingSetup)
 
     unsigned char out_sha_bytes[CSHA256::OUTPUT_SIZE];
     out_sha.Finalize(out_sha_bytes);
-    std::string out_sha_hex = HexStr(std::begin(out_sha_bytes), std::end(out_sha_bytes));
+    std::string out_sha_hex = HexStr(out_sha_bytes);
 
     // If check below fails, should manually dump the results with:
     //
@@ -1125,7 +1102,7 @@ BOOST_FIXTURE_TEST_CASE(util_ChainMerge, ChainMergeTestingSetup)
 
     unsigned char out_sha_bytes[CSHA256::OUTPUT_SIZE];
     out_sha.Finalize(out_sha_bytes);
-    std::string out_sha_hex = HexStr(std::begin(out_sha_bytes), std::end(out_sha_bytes));
+    std::string out_sha_hex = HexStr(out_sha_bytes);
 
     // If check below fails, should manually dump the results with:
     //