Change some tests to use Fraction class in wallet tests

GCC13 and 32 bit x86 seem to have some slightly different results with
floating point that appear to be compiler related. This changes
the relevant tests to use the Fraction class/Allocation class to
use rational arithmetic instead.

src/test/wallet_tests.cpp

@@ -1,5 +1,6 @@
 #include <boost/test/unit_test.hpp>
 
+#include "gridcoin/sidestake.h"
 #include "main.h"
 #include "wallet/wallet.h"
 
@@ -236,18 +237,23 @@ BOOST_AUTO_TEST_CASE(coin_selection_tests)
 
         // test avoiding sub-cent change
         empty_wallet();
-        add_coin(0.0005 * COIN);
-        add_coin(0.01 * COIN);
+        // Use rational arithmetic because the floating point has problems with GCC13 on 32 bit architecture x86.
+        add_coin(static_cast<GRC::Allocation>(Fraction(5, 10000, true) * COIN).ToCAmount());
+        add_coin(static_cast<GRC::Allocation>(Fraction(1, 100, true) * COIN).ToCAmount());
         add_coin(1 * COIN);
 
         // trying to make 1.0001 from these three coins
-        BOOST_CHECK( wallet.SelectCoinsMinConf(1.0001 * COIN, spendTime, 1, 1, vCoins, setCoinsRet, nValueRet));
-        BOOST_CHECK_EQUAL(nValueRet, 1.0105 * COIN);   // we should get all coins
+        BOOST_CHECK( wallet.SelectCoinsMinConf(static_cast<GRC::Allocation>(Fraction(10001, 10000, true) * COIN).ToCAmount(),
+                                              spendTime, 1, 1, vCoins, setCoinsRet, nValueRet));
+        // we should get all coins
+        BOOST_CHECK(nValueRet == static_cast<GRC::Allocation>(Fraction(10105, 10000, true) * COIN).ToCAmount());
         BOOST_CHECK_EQUAL(setCoinsRet.size(), (size_t) 3);
 
         // but if we try to make 0.999, we should take the bigger of the two small coins to avoid sub-cent change
-        BOOST_CHECK( wallet.SelectCoinsMinConf(0.999 * COIN, spendTime, 1, 1, vCoins, setCoinsRet, nValueRet));
-        BOOST_CHECK_EQUAL(nValueRet, 1.01 * COIN);   // we should get 1 + 0.01
+        BOOST_CHECK( wallet.SelectCoinsMinConf(static_cast<GRC::Allocation>(Fraction(999, 1000, true) * COIN).ToCAmount(),
+                                              spendTime, 1, 1, vCoins, setCoinsRet, nValueRet));
+        // we should get 1 + 0.01
+        BOOST_CHECK(nValueRet == static_cast<GRC::Allocation>(Fraction(101, 100, true) * COIN).ToCAmount());
         BOOST_CHECK_EQUAL(setCoinsRet.size(), (size_t) 2);
 
         // test randomness