libeufin

commit 9c7079e5323eed4d16e24c1c4245d6586cecac53
parent d75824cd235b81680ca9e38ad9e6bebb3e3a1010
Author: MS <ms@taler.net>
Date:   Tue,  4 Apr 2023 17:23:20 +0200

Amount comparison.

Checking zero amounts as strings, rather than
via brittle BigDecimal operations.

Diffstat:
M
sandbox/src/main/kotlin/tech/libeufin/sandbox/CircuitApi.kt
 | 
4
++--
M
util/src/main/kotlin/amounts.kt
 | 
9
+++++++++
M
util/src/test/kotlin/AmountTest.kt
 | 
11
+++++++++++

3 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/sandbox/src/main/kotlin/tech/libeufin/sandbox/CircuitApi.kt b/sandbox/src/main/kotlin/tech/libeufin/sandbox/CircuitApi.kt
@@ -804,8 +804,8 @@ fun circuitApi(circuitRoute: Route) {
             resourceName,
             withBankFault = true // See comment "CUSTOMER AND BANK ACCOUNT INVARIANT".
         )
-        val balance = getBalance(bankAccount)
-        if (balance != BigDecimal.ZERO) {
+        val balance: BigDecimal = getBalance(bankAccount)
+        if (!isAmountZero(balance)) {
             logger.error("Account $resourceName has $balance balance.  Won't delete it")
             throw SandboxError(
                 HttpStatusCode.PreconditionFailed,
diff --git a/util/src/main/kotlin/amounts.kt b/util/src/main/kotlin/amounts.kt
@@ -2,6 +2,7 @@ package tech.libeufin.util
 
 import UtilError
 import io.ktor.http.*
+import java.math.BigDecimal
 
 /*
  * This file is part of LibEuFin.
@@ -36,4 +37,12 @@ fun parseAmount(amount: String): AmountWithCurrency {
         throw UtilError(HttpStatusCode.BadRequest, "invalid amount: $amount")
     val (currency, number) = match.destructured
     return AmountWithCurrency(currency = currency, amount = number)
+}
+
+fun isAmountZero(a: BigDecimal): Boolean {
+    a.abs().toPlainString().forEach {
+        if (it != '0' && it != '.')
+            return false
+    }
+    return true
 }
 \ No newline at end of file
diff --git a/util/src/test/kotlin/AmountTest.kt b/util/src/test/kotlin/AmountTest.kt
@@ -1,6 +1,11 @@
+import io.ktor.util.reflect.*
 import org.junit.Test
+import tech.libeufin.sandbox.roundToTwoDigits
+import tech.libeufin.util.isAmountZero
 import tech.libeufin.util.parseAmount
 import tech.libeufin.util.validatePlainAmount
+import java.math.BigDecimal
+import kotlin.reflect.typeOf
 
 inline fun <reified ExceptionType> assertException(block: () -> Unit) {
     try {
@@ -13,6 +18,12 @@ inline fun <reified ExceptionType> assertException(block: () -> Unit) {
 }
 class AmountTest {
     @Test
+    fun equalTest() {
+        val z = BigDecimal("-0000000000.0000000000")
+        assert(isAmountZero(z))
+    }
+
+    @Test
     fun parse() {
         var res = parseAmount("KUDOS:5.5")
         assert(res.amount == "5.5")