BAEL-7894: Basic tests (#16483)

2024-04-24 20:49:05 +02:00
parent 3a0dd5d698
commit 5a12777c4f
1 changed files with 121 additions and 0 deletions
@@ -0,0 +1,121 @@
+package com.baeldung.bigdecimalequalvscompare;
+
+import static java.math.RoundingMode.HALF_UP;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.stream.Stream;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.CsvSource;
+import org.junit.jupiter.params.provider.MethodSource;
+
+class BigDecimalEqualityUnitTest {
+
+    @ParameterizedTest
+    @MethodSource("decimalCompareToProvider")
+    void givenBigDecimals_WhenCompare_ThenGetReasonableResult(BigDecimal fistDecimal,
+      BigDecimal secondDecimal, boolean areComparablySame) {
+        assertEquals(fistDecimal.compareTo(secondDecimal) == 0, areComparablySame);
+    }
+
+
+    @ParameterizedTest
+    @MethodSource("decimalEqualsProvider")
+    void givenBigDecimals_WhenCheckEquality_ThenConsiderPrecision(BigDecimal fistDecimal,
+      BigDecimal secondDecimal, boolean areEqual) {
+        assertEquals(fistDecimal.equals(secondDecimal), areEqual);
+    }
+
+    @ParameterizedTest
+    @MethodSource("decimalEqualsProvider")
+    void givenBigDecimals_WhenCheckEqualityWithoutTrailingZeros_ThenTheSameAsCompareTo(BigDecimal fistDecimal,
+      BigDecimal secondDecimal) {
+        BigDecimal strippedFirstDecimal = fistDecimal.stripTrailingZeros();
+        BigDecimal strippedSecondDecimal = secondDecimal.stripTrailingZeros();
+        assertEquals(strippedFirstDecimal.equals(strippedSecondDecimal),
+          strippedFirstDecimal.compareTo(strippedSecondDecimal) == 0);
+    }
+
+    @ParameterizedTest
+    @MethodSource("decimalProvider")
+    void givenListOfDecimals_WhenAddingToHashSet_ThenUsingEquals(List<BigDecimal> decimalList) {
+        Set<BigDecimal> decimalSet = new HashSet<>(decimalList);
+        assertThat(decimalSet).hasSameElementsAs(decimalList);
+    }
+
+    @ParameterizedTest
+    @MethodSource("decimalProvider")
+    void givenListOfDecimals_WhenAddingToSortedSet_ThenUsingCompareTo(List<BigDecimal> decimalList,
+      List<BigDecimal> expectedDecimalList) {
+        Set<BigDecimal> decimalSet = new TreeSet<>(decimalList);
+        assertThat(decimalSet).hasSameElementsAs(expectedDecimalList);
+    }
+
+    @ParameterizedTest
+    @CsvSource({
+      "2.0, 2.00",
+      "4.0, 4.00"
+    })
+    void givenNumbersWithDifferentPrecision_WhenPerformingTheSameOperation_TheResultsAreDifferent(
+      String firstNumber, String secondNumber) {
+
+        BigDecimal firstResult = new BigDecimal(firstNumber).divide(BigDecimal.valueOf(3), HALF_UP);
+        BigDecimal secondResult = new BigDecimal(secondNumber).divide(BigDecimal.valueOf(3), HALF_UP);
+        assertThat(firstResult).isNotEqualTo(secondResult);
+    }
+
+    static Stream<Arguments> decimalCompareToProvider() {
+        return Stream.of(
+          Arguments.of(new BigDecimal("0.1"), new BigDecimal("0.1"), true),
+          Arguments.of(new BigDecimal("1.1"), new BigDecimal("1.1"), true),
+          Arguments.of(new BigDecimal("1.10"), new BigDecimal("1.1"), true),
+          Arguments.of(new BigDecimal("0.100"), new BigDecimal("0.10000"), true),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1000"), true),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1001"), false),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1010"), false),
+          Arguments.of(new BigDecimal("0.2"), new BigDecimal("0.19999999"), false),
+          Arguments.of(new BigDecimal("1.0"), new BigDecimal("1.1"), false),
+          Arguments.of(new BigDecimal("0.01"), new BigDecimal("0.0099999"), false)
+        );
+    }
+
+    static Stream<Arguments> decimalEqualsProvider() {
+        return Stream.of(
+          Arguments.of(new BigDecimal("0.1"), new BigDecimal("0.1"), true),
+          Arguments.of(new BigDecimal("1.1"), new BigDecimal("1.1"), true),
+          Arguments.of(new BigDecimal("1.10"), new BigDecimal("1.1"), false),
+          Arguments.of(new BigDecimal("0.100"), new BigDecimal("0.10000"), false),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1000"), false),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1001"), false),
+          Arguments.of(new BigDecimal("0.10"), new BigDecimal("0.1010"), false),
+          Arguments.of(new BigDecimal("0.2"), new BigDecimal("0.19999999"), false),
+          Arguments.of(new BigDecimal("1.0"), new BigDecimal("1.1"), false),
+          Arguments.of(new BigDecimal("0.01"), new BigDecimal("0.0099999"), false)
+        );
+    }
+
+    static Stream<Arguments> decimalProvider() {
+        return Stream.of(Arguments.of(Arrays.asList(
+            new BigDecimal("1.1"),
+            new BigDecimal("1.10"),
+            new BigDecimal("1.100"),
+            new BigDecimal("0.10"),
+            new BigDecimal("0.100"),
+            new BigDecimal("0.1000"),
+            new BigDecimal("0.2"),
+            new BigDecimal("0.20"),
+            new BigDecimal("0.200")),
+
+          Arrays.asList(
+            new BigDecimal("1.1"),
+            new BigDecimal("0.10"),
+            new BigDecimal("0.2"))));
+    }
+}