From e67d189b993faa45de2ce069dbd0037c56362c19 Mon Sep 17 00:00:00 2001
From: "willem.romijn" <willem.romijn@cinqict.nl>
Date: Mon, 13 Jan 2025 09:41:54 +0100
Subject: [PATCH] poc - failing tests

---
 .../src/main/kotlin/com/alliander/open/measure/Measure.kt  | 7 +++++--
 .../test/kotlin/com/alliander/open/measure/MeasureTest.kt  | 7 ++++++-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/measure/src/main/kotlin/com/alliander/open/measure/Measure.kt b/measure/src/main/kotlin/com/alliander/open/measure/Measure.kt
index 52c5d88..2f12d23 100644
--- a/measure/src/main/kotlin/com/alliander/open/measure/Measure.kt
+++ b/measure/src/main/kotlin/com/alliander/open/measure/Measure.kt
@@ -43,7 +43,10 @@ data class Measure<U : Units>(val amount: BigDecimal, val units: U) : Comparable
     infix fun <A : U> `in`(other: A): BigDecimal =
         if (units == other)
             amount
-        else (amount * units.ratio).divide(other.ratio, amount.scale() + other.ratio.precision(), RoundingMode.UP)
+        else {
+            val result = (amount * units.ratio).divide(other.ratio)
+            result.setScale(amount.precision() - result.precision() + result.scale(), RoundingMode.UP)
+        }
 
     operator fun plus(other: Measure<U>): Measure<U> = baseUnits(
         units,
@@ -121,4 +124,4 @@ data class Measure<U : Units>(val amount: BigDecimal, val units: U) : Comparable
 }
 
 private fun BigDecimal.roundToMultiple(factor: BigDecimal, roundingMode: RoundingMode): BigDecimal =
-        this.divide(factor, 0, roundingMode) * factor
+    this.divide(factor, 0, roundingMode) * factor
diff --git a/measure/src/test/kotlin/com/alliander/open/measure/MeasureTest.kt b/measure/src/test/kotlin/com/alliander/open/measure/MeasureTest.kt
index 5c20c08..8ff52ad 100644
--- a/measure/src/test/kotlin/com/alliander/open/measure/MeasureTest.kt
+++ b/measure/src/test/kotlin/com/alliander/open/measure/MeasureTest.kt
@@ -24,6 +24,7 @@ import io.kotest.matchers.shouldBe
 import io.kotest.matchers.shouldNotBe
 import io.kotest.property.checkAll
 import java.math.BigDecimal
+import java.math.RoundingMode.HALF_UP
 import java.math.RoundingMode.UP
 
 class MeasureTest : StringSpec({
@@ -222,6 +223,10 @@ class MeasureTest : StringSpec({
     "Unit conversion uses the correct scale" {
         val energyInJoule = 13500000 * joule
         val valueInKwh = energyInJoule `in` kiloWattHour
-        valueInKwh.stripTrailingZeros() shouldBe BigDecimal.valueOf(3.75)
+        valueInKwh shouldBe BigDecimal.valueOf(3.75).setScale(7)
+
+        val energyInKwh = 3.75 * kiloWattHour
+        val valueInJoule = energyInKwh `in` joule
+        valueInJoule shouldBe BigDecimal.valueOf(1.35E+7)
     }
 })