Cover JapaneseChronology with tests.

Cover dateEpochDay method.

Bug: 182165762
Test: atest libcore.java.time.chrono.JapaneseChronologyTest
Change-Id: I216257d767413506d2635794e6925683d86d5e7a
Merged-In: I216257d767413506d2635794e6925683d86d5e7a
(cherry picked from commit 469e077a51f20fd71a0080d67a86fde6fbf19b6b)

1 files changed, 15 insertions, 1 deletions

diff --git a/luni/src/test/java/libcore/java/time/chrono/JapaneseChronologyTest.java b/luni/src/test/java/libcore/java/time/chrono/JapaneseChronologyTest.java
index 5e920b38b20..148c8cd26d9 100644
--- a/luni/src/test/java/libcore/java/time/chrono/JapaneseChronologyTest.java
+++ b/luni/src/test/java/libcore/java/time/chrono/JapaneseChronologyTest.java
@@ -18,6 +18,9 @@ package libcore.java.time.chrono;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
 
+import static java.time.chrono.JapaneseEra.REIWA;
+import static java.time.chrono.JapaneseEra.SHOWA;
+
 import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalTime;
@@ -74,7 +77,7 @@ public class JapaneseChronologyTest {
         // first supported year in JapaneseChronology is Meiji 6.
         assertEquals(JapaneseEra.MEIJI, JapaneseDate.from(LocalDate.of(1873, 1, 1)).getEra());
         assertEquals(JapaneseEra.TAISHO, JapaneseDate.from(LocalDate.of(1913, 1, 1)).getEra());
-        assertEquals(JapaneseEra.SHOWA, JapaneseDate.from(LocalDate.of(1927, 1, 1)).getEra());
+        assertEquals(SHOWA, JapaneseDate.from(LocalDate.of(1927, 1, 1)).getEra());
         assertEquals(JapaneseEra.HEISEI, JapaneseDate.from(LocalDate.of(1990, 1, 1)).getEra());
     }
 
@@ -144,4 +147,15 @@ public class JapaneseChronologyTest {
         assertEquals("Reiwa", reiwaDate.getEra().toString());
     }
 
+    @Test
+    public void dateEpochDay() {
+        JapaneseDate epoch = JapaneseChronology.INSTANCE.dateEpochDay(0);
+        JapaneseDate today = JapaneseChronology.INSTANCE.dateEpochDay(18768);
+        JapaneseDate dayBeforeEpoch = JapaneseChronology.INSTANCE.dateEpochDay(-1);
+
+        assertEquals(JapaneseDate.of(SHOWA, 45, 1, 1), epoch);
+        assertEquals(JapaneseDate.of(REIWA, 3, 5, 21), today);
+        assertEquals(JapaneseDate.of(SHOWA, 44, 12, 31), dayBeforeEpoch);
+    }
+
 }