Add support for unlimited number of decimal places in commodities

Add tests for Money/Commodity
Fix breaking build

app/src/main/java/org/gnucash/android/model/Commodity.java

@@ -179,12 +179,7 @@ public int getSmallestFractionDigits(){
      * @throws IllegalArgumentException if the smallest fraction is not a power of 10
      */
     public void setSmallestFraction(int smallestFraction) {
-        if (smallestFraction != 1 && smallestFraction != 10 && smallestFraction != 100
-                && smallestFraction != 1000 && smallestFraction != 10000
-                && smallestFraction != 1000000 ) //make sure we are not getting digits
-            this.mSmallestFraction = 100;
-        else
-            this.mSmallestFraction = smallestFraction;
+        this.mSmallestFraction = smallestFraction;
     }
 
     public int getQuoteFlag() {

app/src/main/java/org/gnucash/android/model/Money.java

@@ -125,7 +125,7 @@ public Money(BigDecimal amount, Commodity commodity){
 	public Money(String amount, String currencyCode){
 		//commodity has to be set first
 		mCommodity = Commodity.getInstance(currencyCode);
-		setAmount(amount);
+		setAmount(new BigDecimal(amount));
 	}
 
 	/**
@@ -228,11 +228,7 @@ public long getNumerator() {
 	 */
 	public long getDenominator() {
 		int scale = getScale();
-		if (scale == 0){
-			return 0;
-		} else {
-			return Integer.numberOfTrailingZeros(scale);
-		}
+		return BigDecimal.ONE.scaleByPowerOfTen(scale).longValueExact();
 	}
 
 	/**
@@ -291,7 +287,7 @@ public String formattedString(Locale locale){
 		String symbol;
 		if (mCommodity.equals(Commodity.USD) && !locale.equals(Locale.US)) {
 			symbol = "US$";
-		} else if (mCommodity.equals(Commodity.EUR) {
+		} else if (mCommodity.equals(Commodity.EUR)) {
 			symbol = currency.getSymbol(Locale.GERMANY); //euro currency is pretty unique around the world
 		} else {
 			symbol = currency.getSymbol(Locale.US); // US locale has the best symbol formatting table.
@@ -336,16 +332,7 @@ public Money negate(){
 	private void setAmount(@NonNull BigDecimal amount) {
 		mAmount = amount.setScale(mCommodity.getSmallestFractionDigits(), ROUNDING_MODE);
 	}
-
-	/**
-	 * Sets the amount value of this <code>Money</code> object
-	 * The <code>amount</code> is parsed by the {@link BigDecimal} constructor
-	 * @param amount {@link String} amount to be set
-	 */
-	private void setAmount(String amount){
-		setAmount(parseToDecimal(amount));
-	}	
-
+
 	/**
 	 * Returns a new <code>Money</code> object whose value is the sum of the values of 
 	 * this object and <code>addend</code>.
@@ -507,27 +494,6 @@ public int compareTo(@NonNull Money another) {
 		return mAmount.compareTo(another.mAmount);
 	}
 
-	/**
-	 * Parses a Locale specific string into a number using format for {@link Locale#US}
-	 * @param amountString Formatted String amount
-	 * @return String amount formatted in the default locale
-	 */
-    public static BigDecimal parseToDecimal(String amountString){
-		char separator = new DecimalFormatSymbols(Locale.US).getGroupingSeparator();
-		amountString = amountString.replace(Character.toString(separator), "");
-		NumberFormat formatter = NumberFormat.getInstance(Locale.US);		
-		if (formatter instanceof DecimalFormat) {
-		     ((DecimalFormat)formatter).setParseBigDecimal(true);		     
-		}
-		BigDecimal result = new BigDecimal(0);
-		try {
-			result = (BigDecimal) formatter.parse(amountString);
-		} catch (ParseException e) {
-			Crashlytics.logException(e);
-		}
-        return result;
-	}
-
     /**
      * Returns a new instance of {@link Money} object with the absolute value of the current object
      * @return Money object with absolute value of this instance

app/src/test/java/org/gnucash/android/test/unit/model/CommodityTest.java

@@ -27,7 +27,7 @@ public class CommodityTest {
 
     @Test
     public void setSmallestFraction_shouldNotUseDigits(){
-        Commodity commodity = new Commodity("Test", "USD", 4);
+        Commodity commodity = new Commodity("Test", "USD", 100);
         assertThat(commodity.getSmallestFraction()).isEqualTo(100);
 
         commodity.setSmallestFraction(1000);
@@ -36,7 +36,7 @@ public void setSmallestFraction_shouldNotUseDigits(){
 
     @Test
     public void testSmallestFractionDigits(){
-        Commodity commodity = new Commodity("Test", "USD", 4);
+        Commodity commodity = new Commodity("Test", "USD", 100);
         assertThat(commodity.getSmallestFractionDigits()).isEqualTo(2);
 
         commodity.setSmallestFraction(10);

app/src/test/java/org/gnucash/android/test/unit/model/MoneyTest.java

@@ -57,18 +57,15 @@ public void testCreation(){
 
 		Money temp = new Money(amount, CURRENCY_CODE);
 		assertThat("12.25").isEqualTo(temp.toPlainString());
+		assertThat(temp.getNumerator()).isEqualTo(1225L);
+		assertThat(temp.getDenominator()).isEqualTo(100L);
 
 		Commodity commodity = Commodity.getInstance(CURRENCY_CODE);
 		temp = new Money(BigDecimal.TEN, commodity);
 
-		assertEquals("10", temp.asBigDecimal().toPlainString());
+		assertEquals("10.00", temp.asBigDecimal().toPlainString()); //decimal places for EUR currency
 		assertEquals(commodity, temp.getCommodity());
-
-		//test only Locale.US parsing even under different locale
-		Locale.setDefault(Locale.GERMANY);
-		amount = "12,25";
-		temp = new Money(amount, CURRENCY_CODE);
-		assertEquals("1225.00", temp.toPlainString());
+		assertThat("10").isNotEqualTo(temp.asBigDecimal().toPlainString());
 	}
 
 	@Test
@@ -134,6 +131,24 @@ public void testNegation(){
 		validateImmutability();
 	}
 
+	@Test
+	public void testFractionParts(){
+		Money money = new Money("14.15", "USD");
+		assertThat(money.getNumerator()).isEqualTo(1415L);
+		assertThat(money.getDenominator()).isEqualTo(100L);
+
+		money = new Money("125", "JPY");
+		assertThat(money.getNumerator()).isEqualTo(125L);
+		assertThat(money.getDenominator()).isEqualTo(1L);
+	}
+
+	@Test
+	public void nonMatchingCommodityFraction_shouldThrowException(){
+		Money money = new Money("12.345", "JPY");
+		assertThat(money.getNumerator()).isEqualTo(12L);
+		assertThat(money.getDenominator()).isEqualTo(1);
+	}
+
 	@Test
 	public void testPrinting(){
 		assertEquals(mMoneyInEur.asString(), mMoneyInEur.toPlainString());