From 65ad0e998242e1258204b3e0670d5ea40810f467 Mon Sep 17 00:00:00 2001
From: "Erik C. Thauvin" <erik@thauvin.net>
Date: Wed, 26 May 2021 14:18:47 -0700
Subject: [PATCH] Added minFractionDigits parameter to toCurrency.

---
 README.md                                     |  7 +++++--
 .../net/thauvin/erik/crypto/CryptoPrice.kt    |  6 +++---
 .../thauvin/erik/crypto/CryptoPriceTest.kt    | 21 +++++++++++--------
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/README.md b/README.md
index 1ba3489..1203e64 100644
--- a/README.md
+++ b/README.md
@@ -50,8 +50,11 @@ The parameter names match the [Coinbase API](https://developers.coinbase.com/api
 To display the amount as a fomatted currency use the `toCurrency` function:
 
 ```kotlin
-val price = CryptoPrice("BTC", "EUR", 12345.67.toBigDecimal())
-println(price.toCurrency()) // will print €12,345.67
+val euro = CryptoPrice("BTC", "EUR", 12345.67.toBigDecimal())
+println(euro.toCurrency()) // will print: €12,345.67
+
+val krone = CryptoPrice("BTC", "DKK", 12345.67.toBigDecimal())
+println(krone.toCurrency(Locale("da", "DK"))) // will print: 12.345,67 kr.
 ```
 ### Extending
 
diff --git a/src/main/kotlin/net/thauvin/erik/crypto/CryptoPrice.kt b/src/main/kotlin/net/thauvin/erik/crypto/CryptoPrice.kt
index 7248ff7..168a3ae 100644
--- a/src/main/kotlin/net/thauvin/erik/crypto/CryptoPrice.kt
+++ b/src/main/kotlin/net/thauvin/erik/crypto/CryptoPrice.kt
@@ -70,7 +70,7 @@ open class CryptoPrice(val base: String, val currency: String, val amount: BigDe
                     throw CryptoException(message = "Missing price data.")
                 }
             } catch (e: NumberFormatException) {
-                throw CryptoException(message = "Could not convert amount  to number.", cause = e)
+                throw CryptoException(message = "Could not convert amount to number.", cause = e)
             } catch (e: JSONException) {
                 throw CryptoException(message = "Could not parse price data.", cause = e)
             }
@@ -143,10 +143,10 @@ open class CryptoPrice(val base: String, val currency: String, val amount: BigDe
      */
     @JvmOverloads
     @Throws(IllegalArgumentException::class)
-    fun toCurrency(locale: Locale = Locale.getDefault(Locale.Category.FORMAT)): String {
+    fun toCurrency(locale: Locale = Locale.getDefault(Locale.Category.FORMAT), minFractionDigits: Int = 2): String {
         return NumberFormat.getCurrencyInstance(locale).let {
             it.setCurrency(Currency.getInstance(currency))
-            it.setMinimumFractionDigits(2)
+            it.setMinimumFractionDigits(minFractionDigits)
             it.format(amount)
         }
     }    
diff --git a/src/test/kotlin/net/thauvin/erik/crypto/CryptoPriceTest.kt b/src/test/kotlin/net/thauvin/erik/crypto/CryptoPriceTest.kt
index 0a228dc..bbf6166 100644
--- a/src/test/kotlin/net/thauvin/erik/crypto/CryptoPriceTest.kt
+++ b/src/test/kotlin/net/thauvin/erik/crypto/CryptoPriceTest.kt
@@ -85,35 +85,38 @@ class CryptoPriceTest {
     @Test
     @Throws(IllegalArgumentException::class)
     fun testToCurrency() {
-        val d = 12345.67.toBigDecimal()
+        val d = 12345.60.toBigDecimal()
         val usd = CryptoPrice("BTC", "USD", d)
-        assertEquals("$12,345.67", usd.toCurrency(), "EUR format")
+        assertEquals("$12,345.60", usd.toCurrency(), "EUR format")
 
         val eur = CryptoPrice("BTC", "EUR", d)
-        assertEquals("€12,345.67", eur.toCurrency(), "EUR format")
+        assertEquals("€12,345.60", eur.toCurrency(), "EUR format")
 
         val gbp = CryptoPrice("ETH", "GBP", d)
-        assertEquals("£12,345.67", gbp.toCurrency(), "GBP format")
+        assertEquals("£12,345.60", gbp.toCurrency(), "GBP format")
 
         val aud = CryptoPrice("BTC", "AUD", d)
-        assertEquals("A$12,345.67", aud.toCurrency(), "AUD format")
+        assertEquals("A$12,345.60", aud.toCurrency(), "AUD format")
 
         val dk = CryptoPrice("BTC", "DKK", d)
-        assertEquals("12.345,67 kr.", dk.toCurrency(Locale("da", "DK")), "EUR-DKK format")
+        assertEquals("12.345,60 kr.", dk.toCurrency(Locale("da", "DK")), "EUR-DKK format")
 
         val jp = CryptoPrice("BTC", "JPY", d)
-        assertEquals("￥12,345.67", jp.toCurrency(Locale.JAPAN), "EUR-JPY format")
+        assertEquals("￥12,345.60", jp.toCurrency(Locale.JAPAN), "EUR-JPY format")
+
+        assertEquals("$12,345.6000", usd.toCurrency(minFractionDigits = 4), "minFractionDigits = 4")
+        assertEquals("$12,345.6", usd.toCurrency(minFractionDigits = 0), "minFractionDigits = 0")
     }
 
     @Test
     @Throws(CryptoException::class)
     fun testToPrice() {
-        val d = "57515.69"
+        val d = "57515.60"
         val json = "{\"data\":{\"base\":\"BTC\",\"currency\":\"USD\",\"amount\":\"$d\"}}"
         val price = json.toPrice()
         assertEquals("BTC", price.base, "base is BTC")
         assertEquals("USD", price.currency, "currency is USD")
-        assertEquals(d, price.amount.toString(), "amount is 57515.69")
+        assertEquals(d, price.amount.toString(), "amount is 57515.60")
 
         assertFailsWith(
             message = "double conversion did not fail",