Is it a valid fix ????

src/test/app/Vault_test.cpp

@@ -2446,6 +2446,47 @@ class Vault_test : public beast::unit_test::suite
         }
     }
 
+    void
+    testIOURounding()
+    {
+        using namespace test::jtx;
+        testcase("IOU rounding");
+
+        Account const issuer{"issuer"};
+        Account const owner{"owner"};
+        auto const IOU = issuer["IOU"];
+        Env env{*this};
+        Vault vault{env};
+
+        env.fund(XRP(1'000), issuer, owner);
+        env.close();
+
+        env(trust(owner, IOU(1'000)));
+        env(pay(issuer, owner, IOU(118.75)));
+        env.close();
+
+        auto [tx, vaultKeylet] =
+            vault.create({.owner = owner, .asset = IOU.asset()});
+        tx[sfScale] = 1;
+        env(tx);
+
+        env.close();
+
+        env(vault.deposit(
+            {.depositor = owner, .id = vaultKeylet.key, .amount = IOU(100)}));
+        env.close();
+
+        auto const tx1 = vault.deposit(
+            {.depositor = owner, .id = vaultKeylet.key, .amount = IOU(3.75)});
+        for (auto i = 0; i < 5; ++i)
+        {
+            if (i == 4)
+                std::cerr << tx1 << '\n';
+            env(tx1);
+            env.close();
+        }
+    }
+
     void
     testWithIOU()
     {
@@ -4973,20 +5014,21 @@ public:
     void
     run() override
     {
-        testSequences();
-        testPreflight();
-        testCreateFailXRP();
-        testCreateFailIOU();
-        testCreateFailMPT();
-        testWithMPT();
-        testWithIOU();
-        testWithDomainCheck();
-        testWithDomainCheckXRP();
-        testNonTransferableShares();
-        testFailedPseudoAccount();
-        testScaleIOU();
-        testRPC();
-        testDelegate();
+        // testSequences();
+        // testPreflight();
+        // testCreateFailXRP();
+        // testCreateFailIOU();
+        // testCreateFailMPT();
+        // testWithMPT();
+        // testWithIOU();
+        testIOURounding();
+        // testWithDomainCheck();
+        // testWithDomainCheckXRP();
+        // testNonTransferableShares();
+        // testFailedPseudoAccount();
+        // testScaleIOU();
+        // testRPC();
+        // testDelegate();
     }
 };
 

src/test/protocol/STAmount_test.cpp

@@ -1011,25 +1011,41 @@ public:
         }
     }
 
+    void
+    testRoundingError()
+    {
+        testcase("rounding error");
+
+        STAmount assets{noIssue()};
+        STAmount const shares{noIssue(), 37, 0};
+        Number const shareTotal{1148};
+        Number assetTotal{1148, -1};
+
+        assets = (assetTotal * shares) / shareTotal;
+        std::cerr << assets << '\n';              // 3.699999999999999/1/1
+        BEAST_EXPECT(assets == Number(37l, -1));  // FAIL
+    }
+
     //--------------------------------------------------------------------------
 
     void
     run() override
     {
-        testSetValue();
-        testNativeCurrency();
-        testCustomCurrency();
-        testArithmetic();
-        testUnderflow();
-        testRounding();
-        testConvertXRP();
-        testConvertIOU();
-        testCanAddXRP();
-        testCanAddIOU();
-        testCanAddMPT();
-        testCanSubtractXRP();
-        testCanSubtractIOU();
-        testCanSubtractMPT();
+        // testSetValue();
+        // testNativeCurrency();
+        // testCustomCurrency();
+        // testArithmetic();
+        // testUnderflow();
+        // testRounding();
+        // testConvertXRP();
+        // testConvertIOU();
+        // testCanAddXRP();
+        // testCanAddIOU();
+        // testCanAddMPT();
+        // testCanSubtractXRP();
+        // testCanSubtractIOU();
+        // testCanSubtractMPT();
+        testRoundingError();
     }
 };