Rename XRPL_ASSERT2 to XRPL_ASSERT_PARTS, and document it

include/xrpl/beast/utility/instrumentation.h

@@ -39,13 +39,16 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #endif
 
 #define XRPL_ASSERT ALWAYS_OR_UNREACHABLE
-#define XRPL_ASSERT2(cond, location, message, ...) \
-    XRPL_ASSERT(cond, location " : " message)
+#define XRPL_ASSERT_PARTS(cond, function, description, ...) \
+    XRPL_ASSERT(cond, function " : " description)
 
 // How to use the instrumentation macros:
 //
 // * XRPL_ASSERT if cond must be true but the line might not be reached during
 //   fuzzing. Same like `assert` in normal use.
+// * XRPL_ASSERT_PARTS is for convenience, and works like XRPL_ASSERT, but
+//   splits the message param into "function" and "description", then joins
+//   them with " : " before passing to XRPL_ASSERT.
 // * ALWAYS if cond must be true _and_ the line must be reached during fuzzing.
 //   Same like `assert` in normal use.
 // * REACHABLE if the line must be reached during fuzzing

src/xrpld/app/tx/detail/LoanPay.cpp

@@ -230,7 +230,7 @@ LoanPay::doApply()
     // Move funds
     STAmount const paidToVault(asset, totalPaidToVault);
     STAmount const paidToBroker(asset, totalFee);
-    XRPL_ASSERT2(
+    XRPL_ASSERT_PARTS(
         paidToVault + paidToBroker == amount,
         "ripple::LoanPay::doApply",
         "correct payment totals");