Understand loan interest rates properly (fixes #401)

Loan interests from Zonky come as percentages, while strategy expects them to be a hundred times that.
RoboZonky · Mar 12, 2019 · ebf35f9 · ebf35f9
1 parent 4b970de
commit ebf35f9
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Showing 8 changed files with 63 additions and 14 deletions.
diff --git a/...strategy-natural/src/main/java/com/github/robozonky/strategy/natural/AbstractWrapper.java b/...strategy-natural/src/main/java/com/github/robozonky/strategy/natural/AbstractWrapper.java
@@ -16,9 +16,14 @@
 
 package com.github.robozonky.strategy.natural;
 
+import java.math.BigDecimal;
 import java.util.Objects;
 
+import com.github.robozonky.api.remote.entities.Participation;
+import com.github.robozonky.api.remote.entities.sanitized.Investment;
+import com.github.robozonky.api.remote.entities.sanitized.Loan;
 import com.github.robozonky.api.strategies.Descriptor;
+import com.github.robozonky.internal.util.BigDecimalCalculator;
 
 abstract class AbstractWrapper<T extends Descriptor<?, ?, ?>> implements Wrapper<T> {
 
@@ -28,6 +33,17 @@ protected AbstractWrapper(final T original) {
         this.original = original;
     }
 
+    /**
+     * Rates are coming from the API ({@link Investment}, {@link Loan}, {@link Participation}) in the form of a share
+     * (1 % becomes "0.01"), while the strategy excepts them in the format of a percentage (1 & becomes "1"). This
+     * method converts from the former to the latter.
+     * @param bigDecimal
+     * @return
+     */
+    protected static BigDecimal adjustRateForStrategy(final BigDecimal bigDecimal) {
+        return BigDecimalCalculator.times(bigDecimal, 100);
+    }
+
     @Override
     public T getOriginal() {
         return original;
@@ -50,5 +66,4 @@ public boolean equals(final Object o) {
     public int hashCode() {
         return Objects.hash(original);
     }
-
 }
diff --git a/...rategy-natural/src/main/java/com/github/robozonky/strategy/natural/InvestmentWrapper.java b/...rategy-natural/src/main/java/com/github/robozonky/strategy/natural/InvestmentWrapper.java
@@ -45,12 +45,12 @@ public MainIncomeType getMainIncomeType() {
 
     @Override
     public BigDecimal getInterestRate() {
-        return investment.getInterestRate();
+        return adjustRateForStrategy(investment.getInterestRate());
     }
 
     @Override
     public BigDecimal getRevenueRate() {
-        return investment.getRevenueRate();
+        return adjustRateForStrategy(investment.getRevenueRate());
     }
 
     @Override

diff --git a/...nky-strategy-natural/src/main/java/com/github/robozonky/strategy/natural/LoanWrapper.java b/...nky-strategy-natural/src/main/java/com/github/robozonky/strategy/natural/LoanWrapper.java
@@ -56,12 +56,12 @@ public MainIncomeType getMainIncomeType() {
 
     @Override
     public BigDecimal getInterestRate() {
-        return loan.getInterestRate();
+        return adjustRateForStrategy(loan.getInterestRate());
     }
 
     @Override
     public BigDecimal getRevenueRate() {
-        return loan.getRevenueRate();
+        return adjustRateForStrategy(loan.getRevenueRate());
     }
 
     @Override

diff --git a/...egy-natural/src/main/java/com/github/robozonky/strategy/natural/ParticipationWrapper.java b/...egy-natural/src/main/java/com/github/robozonky/strategy/natural/ParticipationWrapper.java
@@ -45,12 +45,12 @@ public MainIncomeType getMainIncomeType() {
 
     @Override
     public BigDecimal getInterestRate() {
-        return participation.getInterestRate();
+        return adjustRateForStrategy(participation.getInterestRate());
     }
 
     @Override
-    public BigDecimal getRevenueRate() { // TODO check if Participation has this field too
-        return getLoan().getRevenueRate();
+    public BigDecimal getRevenueRate() {
+        return adjustRateForStrategy(getLoan().getRevenueRate());
     }
 
     @Override

diff --git a/...nky-strategy-natural/src/test/java/com/github/robozonky/strategy/natural/WrapperTest.java b/...nky-strategy-natural/src/test/java/com/github/robozonky/strategy/natural/WrapperTest.java
@@ -24,6 +24,7 @@
 import com.github.robozonky.api.strategies.LoanDescriptor;
 import org.junit.jupiter.api.Test;
 
+import static com.github.robozonky.internal.util.BigDecimalCalculator.times;
 import static org.assertj.core.api.SoftAssertions.assertSoftly;
 
 class WrapperTest {
@@ -34,6 +35,7 @@ void fromInvestment() {
                 .setId(1)
                 .setAmount(100_000)
                 .setRevenueRate(BigDecimal.ONE)
+                .setInterestRate(BigDecimal.TEN)
                 .setAnnuity(BigDecimal.ONE)
                 .build();
         final int invested = 200;
@@ -44,8 +46,8 @@ void fromInvestment() {
             softly.assertThat(w.getRegion()).isEqualTo(loan.getRegion());
             softly.assertThat(w.getRating()).isEqualTo(loan.getRating());
             softly.assertThat(w.getOriginalAmount()).isEqualTo(loan.getAmount());
-            softly.assertThat(w.getInterestRate()).isEqualTo(loan.getInterestRate());
-            softly.assertThat(w.getRevenueRate()).isEqualTo(investment.getRevenueRate());
+            softly.assertThat(w.getInterestRate()).isEqualTo(times(loan.getInterestRate(), 100));
+            softly.assertThat(w.getRevenueRate()).isEqualTo(times(investment.getRevenueRate(), 100));
             softly.assertThat(w.getOriginalAnnuity()).isEqualTo(loan.getAnnuity().intValue());
             softly.assertThat(w.getRemainingTermInMonths()).isEqualTo(investment.getRemainingMonths());
             softly.assertThat(w.getRemainingPrincipal()).isEqualTo(BigDecimal.valueOf(invested));

diff --git a/...src/test/java/com/github/robozonky/strategy/natural/conditions/InvestmentWrapperTest.java b/...src/test/java/com/github/robozonky/strategy/natural/conditions/InvestmentWrapperTest.java
@@ -29,6 +29,7 @@
 import com.github.robozonky.strategy.natural.Wrapper;
 import org.junit.jupiter.api.Test;
 
+import static com.github.robozonky.internal.util.BigDecimalCalculator.times;
 import static org.assertj.core.api.SoftAssertions.assertSoftly;
 
 class InvestmentWrapperTest {
@@ -52,7 +53,7 @@ void values() {
         final Wrapper<InvestmentDescriptor> w = Wrapper.wrap(original);
         assertSoftly(softly -> {
             softly.assertThat(w.isInsuranceActive()).isEqualTo(INVESTMENT.isInsuranceActive());
-            softly.assertThat(w.getInterestRate()).isEqualTo(INVESTMENT.getInterestRate());
+            softly.assertThat(w.getInterestRate()).isEqualTo(times(INVESTMENT.getInterestRate(), 100));
             softly.assertThat(w.getRegion()).isEqualTo(LOAN.getRegion());
             softly.assertThat(w.getRating()).isEqualTo(INVESTMENT.getRating());
             softly.assertThat(w.getMainIncomeType()).isEqualTo(LOAN.getMainIncomeType());

diff --git a/...tural/src/test/java/com/github/robozonky/strategy/natural/conditions/LoanWrapperTest.java b/...tural/src/test/java/com/github/robozonky/strategy/natural/conditions/LoanWrapperTest.java
@@ -28,6 +28,7 @@
 import com.github.robozonky.strategy.natural.Wrapper;
 import org.junit.jupiter.api.Test;
 
+import static com.github.robozonky.internal.util.BigDecimalCalculator.times;
 import static org.assertj.core.api.SoftAssertions.assertSoftly;
 
 class LoanWrapperTest {
@@ -49,7 +50,7 @@ void values() {
         final Wrapper<LoanDescriptor> w = Wrapper.wrap(original);
         assertSoftly(softly -> {
             softly.assertThat(w.isInsuranceActive()).isEqualTo(l.isInsuranceActive());
-            softly.assertThat(w.getInterestRate()).isEqualTo(l.getInterestRate());
+            softly.assertThat(w.getInterestRate()).isEqualTo(times(l.getInterestRate(), 100));
             softly.assertThat(w.getRegion()).isEqualTo(l.getRegion());
             softly.assertThat(w.getRating()).isEqualTo(l.getRating());
             softly.assertThat(w.getMainIncomeType()).isEqualTo(l.getMainIncomeType());
@@ -87,5 +88,4 @@ void equality() {
             softly.assertThat(w).isNotEqualTo(null);
         });
     }
-
 }
diff --git a/.../test/java/com/github/robozonky/strategy/natural/conditions/ParticipationWrapperTest.java b/.../test/java/com/github/robozonky/strategy/natural/conditions/ParticipationWrapperTest.java
@@ -17,6 +17,8 @@
 package com.github.robozonky.strategy.natural.conditions;
 
 import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.UUID;
 
 import com.github.robozonky.api.remote.entities.Participation;
@@ -26,9 +28,12 @@
 import com.github.robozonky.api.remote.enums.Rating;
 import com.github.robozonky.api.remote.enums.Region;
 import com.github.robozonky.api.strategies.ParticipationDescriptor;
+import com.github.robozonky.internal.util.BigDecimalCalculator;
 import com.github.robozonky.strategy.natural.Wrapper;
 import org.junit.jupiter.api.Test;
 
+import static com.github.robozonky.internal.util.BigDecimalCalculator.times;
+import static org.assertj.core.api.Assertions.*;
 import static org.assertj.core.api.SoftAssertions.assertSoftly;
 import static org.mockito.Mockito.*;
 
@@ -49,6 +54,7 @@ class ParticipationWrapperTest {
 
     private static Participation mockParticipation(final Loan loan) {
         final Participation p = mock(Participation.class);
+        when(p.getInterestRate()).thenReturn(BigDecimal.ONE);
         when(p.getPurpose()).thenReturn(loan.getPurpose());
         when(p.getRating()).thenReturn(loan.getRating());
         when(p.getIncomeType()).thenReturn(loan.getMainIncomeType());
@@ -61,7 +67,7 @@ void values() {
         final Wrapper<ParticipationDescriptor> w = Wrapper.wrap(original);
         assertSoftly(softly -> {
             softly.assertThat(w.isInsuranceActive()).isEqualTo(PARTICIPATION.isInsuranceActive());
-            softly.assertThat(w.getInterestRate()).isEqualTo(PARTICIPATION.getInterestRate());
+            softly.assertThat(w.getInterestRate()).isEqualTo(times(PARTICIPATION.getInterestRate(), 100));
             softly.assertThat(w.getRegion()).isEqualTo(LOAN.getRegion());
             softly.assertThat(w.getRating()).isEqualTo(PARTICIPATION.getRating());
             softly.assertThat(w.getMainIncomeType()).isEqualTo(LOAN.getMainIncomeType());
@@ -87,4 +93,29 @@ void equality() {
             softly.assertThat(w).isNotEqualTo(null);
         });
     }
+
+    @Test
+    void elseConditionWorks() {
+        final AbstractEnumeratedCondition<Region> c = new BorrowerRegionCondition();
+        c.add(Region.USTECKY);
+        c.add(Region.MORAVSKOSLEZSKY);
+        c.add(Region.KARLOVARSKY);
+        final MarketplaceFilter f = new MarketplaceFilter();
+        f.when(Collections.singleton(c));
+        final AbstractEnumeratedCondition<MainIncomeType> c2 = new BorrowerIncomeCondition();
+        c2.add(MainIncomeType.EMPLOYMENT);
+        final AbstractRangeCondition c3 =
+                new LoanInterestRateCondition(BigDecimal.ZERO, BigDecimalCalculator.lessThan(new BigDecimal("16.0")));
+        f.butNotWhen(Arrays.asList(c2, c3));
+        final Loan l = Loan.custom()
+                .setRegion(Region.USTECKY)
+                .build();
+        final Participation p = mock(Participation.class);
+        when(p.getIncomeType()).thenReturn(MainIncomeType.EMPLOYMENT);
+        when(p.getInterestRate()).thenReturn(new BigDecimal("0.15"));
+        final ParticipationDescriptor pd = new ParticipationDescriptor(p, () -> l);
+        final Wrapper<ParticipationDescriptor> w = Wrapper.wrap(pd);
+        assertThat(f).rejects(w);
+    }
+
 }