Add hardcoded hash test back

include/xrpl/protocol/Feature.h

@@ -84,6 +84,12 @@
 
 namespace ripple {
 
+// We do not want feature names to exceed this size.
+static constexpr std::size_t maxFeatureNameSize = 63;
+// We not want feature names of this length (and + 1), to enable the use of
+// 32-long byte string for selection of feature as uint256, in WASM
+static constexpr std::size_t reservedFeatureNameSize = 32;
+
 enum class VoteBehavior : int { Obsolete = -1, DefaultNo = 0, DefaultYes };
 enum class AmendmentSupport : int { Retired = -1, Supported = 0, Unsupported };
 

src/libxrpl/protocol/Feature.cpp

@@ -443,10 +443,22 @@ featureToName(uint256 const& f)
 #pragma push_macro("XRPL_ABANDON")
 #undef XRPL_ABANDON
 
+template <std::size_t N>
+constexpr auto
+enforceMaxFeatureNameSize(char const (&n)[N]) -> char const*
+{
+    static_assert(N != reservedFeatureNameSize);
+    static_assert(N != reservedFeatureNameSize + 1);
+    static_assert(N <= maxFeatureNameSize);
+    return n;
+}
+
 #define XRPL_FEATURE(name, supported, vote) \
-    uint256 const feature##name = registerFeature(#name, supported, vote);
-#define XRPL_FIX(name, supported, vote) \
-    uint256 const fix##name = registerFeature("fix" #name, supported, vote);
+    uint256 const feature##name =           \
+        registerFeature(enforceMaxFeatureNameSize(#name), supported, vote);
+#define XRPL_FIX(name, supported, vote)        \
+    uint256 const fix##name = registerFeature( \
+        enforceMaxFeatureNameSize("fix" #name), supported, vote);
 
 // clang-format off
 #define XRPL_RETIRE(name)                                       \

src/test/rpc/Feature_test.cpp

@@ -22,6 +22,7 @@
 #include <xrpld/app/misc/AmendmentTable.h>
 
 #include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/digest.h>
 #include <xrpl/protocol/jss.h>
 
 namespace ripple {
@@ -202,16 +203,20 @@ class Feature_test : public beast::unit_test::suite
         using namespace test::jtx;
         Env env{*this};
 
-        auto jrr = env.rpc("feature", "MultiSignReserve")[jss::result];
+        std::string const name = "MultiSignReserve";
+        auto jrr = env.rpc("feature", name)[jss::result];
         BEAST_EXPECTS(jrr[jss::status] == jss::success, "status");
         jrr.removeMember(jss::status);
         BEAST_EXPECT(jrr.size() == 1);
-        BEAST_EXPECT(
-            jrr.isMember("586480873651E106F1D6339B0C4A8945BA705A777F3F4524626FF"
-                         "1FC07EFE41D"));
+        auto const expected =
+            to_string(sha512Half(Slice(name.data(), name.size())));
+        char const sha[] =
+            "586480873651E106F1D6339B0C4A8945BA705A777F3F4524626FF1FC07EFE41D";
+        BEAST_EXPECT(expected == sha);
+        BEAST_EXPECT(jrr.isMember(expected));
         auto feature = *(jrr.begin());
 
-        BEAST_EXPECTS(feature[jss::name] == "MultiSignReserve", "name");
+        BEAST_EXPECTS(feature[jss::name] == name, "name");
         BEAST_EXPECTS(!feature[jss::enabled].asBool(), "enabled");
         BEAST_EXPECTS(
             feature[jss::vetoed].isBool() && !feature[jss::vetoed].asBool(),