1 files changed, 50 insertions, 15 deletions

diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index b73acc1de5..f9cf5d9157 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -10,9 +10,12 @@
 #include <key.h>
 #include <node/caches.h>
 #include <node/context.h> // IWYU pragma: export
+#include <optional>
+#include <ostream>
 #include <primitives/transaction.h>
 #include <pubkey.h>
 #include <stdexcept>
+#include <test/util/random.h>
 #include <util/chaintype.h> // IWYU pragma: export
 #include <util/check.h>
 #include <util/fs.h>
@@ -28,6 +31,8 @@ class arith_uint256;
 class CFeeRate;
 class Chainstate;
 class FastRandomContext;
+class uint160;
+class uint256;
 
 /** This is connected to the logger. Can be used to redirect logs to any other log */
 extern const std::function<void(const std::string&)> G_TEST_LOG_FUN;
@@ -38,15 +43,6 @@ extern const std::function<std::vector<const char*>()> G_TEST_COMMAND_LINE_ARGUM
 /** Retrieve the unit test name. */
 extern const std::function<std::string()> G_TEST_GET_FULL_NAME;
 
-// Enable BOOST_CHECK_EQUAL for enum class types
-namespace std {
-template <typename T>
-std::ostream& operator<<(typename std::enable_if<std::is_enum<T>::value, std::ostream>::type& stream, const T& e)
-{
-    return stream << static_cast<typename std::underlying_type<T>::type>(e);
-}
-} // namespace std
-
 static constexpr CAmount CENT{1000000};
 
 struct TestOpts {
@@ -65,12 +61,37 @@ struct BasicTestingSetup {
     util::SignalInterrupt m_interrupt;
     node::NodeContext m_node; // keep as first member to be destructed last
 
+    FastRandomContext m_rng;
+    /** Seed the global RNG state and m_rng for testing and log the seed value. This affects all randomness, except GetStrongRandBytes(). */
+    void SeedRandomForTest(SeedRand seed)
+    {
+        SeedRandomStateForTest(seed);
+        m_rng.Reseed(GetRandHash());
+    }
+
     explicit BasicTestingSetup(const ChainType chainType = ChainType::MAIN, TestOpts = {});
     ~BasicTestingSetup();
 
     fs::path m_path_root;
     fs::path m_path_lock;
     bool m_has_custom_datadir{false};
+    /** @brief Test-specific arguments and settings.
+     *
+     * This member is intended to be the primary source of settings for code
+     * being tested by unit tests. It exists to make tests more self-contained
+     * and reduce reliance on global state.
+     *
+     * Usage guidelines:
+     * 1. Prefer using m_args where possible in test code.
+     * 2. If m_args is not accessible, use m_node.args as a fallback.
+     * 3. Avoid direct references to gArgs in test code.
+     *
+     * Note: Currently, m_node.args points to gArgs for backwards
+     * compatibility. In the future, it will point to m_args to further isolate
+     * test environments.
+     *
+     * @see https://github.com/bitcoin/bitcoin/issues/25055 for additional context.
+     */
     ArgsManager m_args;
 };
 
@@ -241,10 +262,26 @@ std::unique_ptr<T> MakeNoLogFileContext(const ChainType chain_type = ChainType::
 
 CBlock getBlock13b8a();
 
-// Make types usable in BOOST_CHECK_*
+// Make types usable in BOOST_CHECK_* @{
+namespace std {
+template <typename T> requires std::is_enum_v<T>
+inline std::ostream& operator<<(std::ostream& os, const T& e)
+{
+    return os << static_cast<std::underlying_type_t<T>>(e);
+}
+
+template <typename T>
+inline std::ostream& operator<<(std::ostream& os, const std::optional<T>& v)
+{
+    return v ? os << *v
+             : os << "std::nullopt";
+}
+} // namespace std
+
 std::ostream& operator<<(std::ostream& os, const arith_uint256& num);
 std::ostream& operator<<(std::ostream& os, const uint160& num);
 std::ostream& operator<<(std::ostream& os, const uint256& num);
+// @}
 
 /**
  * BOOST_CHECK_EXCEPTION predicates to check the specific validation error.
@@ -254,11 +291,9 @@ std::ostream& operator<<(std::ostream& os, const uint256& num);
 class HasReason
 {
 public:
-    explicit HasReason(const std::string& reason) : m_reason(reason) {}
-    bool operator()(const std::exception& e) const
-    {
-        return std::string(e.what()).find(m_reason) != std::string::npos;
-    };
+    explicit HasReason(std::string_view reason) : m_reason(reason) {}
+    bool operator()(std::string_view s) const { return s.find(m_reason) != std::string_view::npos; }
+    bool operator()(const std::exception& e) const { return (*this)(e.what()); }
 
 private:
     const std::string m_reason;