precompiles: Add basic SHA256 unit tests

test/unittests/CMakeLists.txt

@@ -48,6 +48,7 @@ target_sources(
     instructions_test.cpp
     precompiles_blake2b_test.cpp
     precompiles_ripemd160_test.cpp
+    precompiles_sha256_test.cpp
     state_block_test.cpp
     state_bloom_filter_test.cpp
     state_difficulty_test.cpp

test/unittests/precompiles_sha256_test.cpp

@@ -0,0 +1,32 @@
+// evmone: Fast Ethereum Virtual Machine implementation
+// Copyright 2024 The evmone Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+#include <evmc/hex.hpp>
+#include <evmone_precompiles/sha256.hpp>
+#include <gtest/gtest.h>
+
+using evmone::crypto::sha256;
+
+TEST(sha256, test_vectors)
+{
+    // Some test vectors from https://www.di-mgt.com.au/sha_testvectors.html.
+
+    const std::pair<std::string_view, std::string_view> test_cases[] = {
+        {"", "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"},
+        {"abc", "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"},
+        {"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
+            "248d6a61d20638b8e5c026930c3e6039a33ce45964ff2167f6ecedd419db06c1"},
+        {"abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmn"
+         "hijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu",
+            "cf5b16a778af8380036ce59e7b0492370b249b11e8f07a51afac45037afee9d1"},
+    };
+
+    for (const auto& [input, expected_hash_hex] : test_cases)
+    {
+        std::byte hash[evmone::crypto::SHA256_HASH_SIZE];
+        sha256(hash, reinterpret_cast<const std::byte*>(input.data()), input.size());
+        const auto hash_hex = evmc::hex({reinterpret_cast<const uint8_t*>(hash), std::size(hash)});
+        EXPECT_EQ(hash_hex, expected_hash_hex);
+    }
+}