adding support for Month data type - pgjdbcgh-591

src/main/java/io/r2dbc/postgresql/codec/DefaultCodecs.java

@@ -253,14 +253,15 @@ private static List<Codec<?>> getDefaultCodecs(ByteBufAllocator byteBufAllocator
             new LocalDateTimeCodec(byteBufAllocator, configuration::getZoneId),
             new LocalTimeCodec(byteBufAllocator),
             new LongCodec(byteBufAllocator),
+            new MonthCodec(byteBufAllocator),
             new OffsetDateTimeCodec(byteBufAllocator),
             new OffsetTimeCodec(byteBufAllocator),
             new ShortCodec(byteBufAllocator),
             new UriCodec(byteBufAllocator),
             new UrlCodec(byteBufAllocator),
             new UuidCodec(byteBufAllocator),
-            new ZoneIdCodec(byteBufAllocator),
             new YearCodec(byteBufAllocator),
+            new ZoneIdCodec(byteBufAllocator),
 
             // JSON
             new JsonCodec(byteBufAllocator, preferAttachedBuffers),

src/main/java/io/r2dbc/postgresql/codec/MonthCodec.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.r2dbc.postgresql.codec;
+
+import io.netty.buffer.ByteBufAllocator;
+
+import java.time.Month;
+
+final class MonthCodec extends IntegerCodecDelegate<Month> {
+
+    MonthCodec(ByteBufAllocator byteBufAllocator) {
+        super(Month.class, byteBufAllocator, Month::getValue, Month::of);
+    }
+}

src/test/java/io/r2dbc/postgresql/codec/MonthCodecTest.java

@@ -0,0 +1,109 @@
+package io.r2dbc.postgresql.codec;
+
+import io.r2dbc.postgresql.client.EncodedParameter;
+import io.r2dbc.postgresql.client.ParameterAssert;
+import org.junit.jupiter.api.Test;
+
+import java.time.Month;
+import java.util.Arrays;
+import java.util.function.Consumer;
+
+import static io.r2dbc.postgresql.client.EncodedParameter.NULL_VALUE;
+import static io.r2dbc.postgresql.codec.PostgresqlObjectId.*;
+import static io.r2dbc.postgresql.message.Format.FORMAT_BINARY;
+import static io.r2dbc.postgresql.message.Format.FORMAT_TEXT;
+import static io.r2dbc.postgresql.util.TestByteBufAllocator.TEST;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+
+class MonthCodecTest {
+
+    @Test
+    void constructorNoByteBufAllocator() {
+        assertThatIllegalArgumentException().isThrownBy(() -> new MonthCodec(null))
+                .withMessage("byteBufAllocator must not be null");
+    }
+
+
+    @Test
+    void decode() {
+        forEveryMonth(m ->
+                assertThat(new MonthCodec(TEST).decode(TEST.buffer().writeInt(m.getValue()), INT4, FORMAT_BINARY, Month.class)).isEqualTo(m));
+    }
+
+    @Test
+    void decodeNoByteBuf() {
+        assertThat(new MonthCodec(TEST).decode(null, INT4.getObjectId(), FORMAT_BINARY, Month.class)).isNull();
+    }
+
+    @Test
+    void doCanDecode() {
+        MonthCodec codec = new MonthCodec(TEST);
+
+        assertThat(codec.doCanDecode(INT4, FORMAT_BINARY)).isTrue();
+        assertThat(codec.doCanDecode(INT2, FORMAT_BINARY)).isTrue();
+        assertThat(codec.doCanDecode(INT8, FORMAT_BINARY)).isTrue();
+        assertThat(codec.doCanDecode(NUMERIC, FORMAT_TEXT)).isTrue();
+        assertThat(codec.doCanDecode(VARCHAR, FORMAT_TEXT)).isFalse();
+    }
+
+    @Test
+    void doCanDecodeNoType() {
+        assertThatIllegalArgumentException().isThrownBy(() -> new MonthCodec(TEST).doCanDecode(null, FORMAT_BINARY))
+                .withMessage("type must not be null");
+    }
+
+    @Test
+    void doEncodeInt() {
+
+        forEveryMonth(m -> {
+            ParameterAssert.assertThat(new MonthCodec(TEST).doEncode(m))
+                    .hasFormat(FORMAT_BINARY)
+                    .hasType(INT4.getObjectId())
+                    .hasValue(TEST.buffer().writeInt(m.getValue()));
+        });
+    }
+
+    @Test
+    void doEncodeShort() {
+        forEveryMonth(m -> {
+            ParameterAssert.assertThat(new MonthCodec(TEST).doEncode(m, INT2))
+                    .hasFormat(FORMAT_BINARY)
+                    .hasType(INT2.getObjectId())
+                    .hasValue(TEST.buffer().writeShort(m.getValue()));
+        });
+    }
+
+    @Test
+    void doEncodeLong() {
+
+        forEveryMonth(m -> {
+            ParameterAssert.assertThat(new MonthCodec(TEST).doEncode(m, INT8))
+                    .hasFormat(FORMAT_BINARY)
+                    .hasType(INT8.getObjectId())
+                    .hasValue(TEST.buffer().writeLong(m.getValue()));
+        });
+    }
+
+    @Test
+    void doEncodeNoValue() {
+        assertThatIllegalArgumentException().isThrownBy(() -> new MonthCodec(TEST).doEncode(null))
+                .withMessage("value must not be null");
+    }
+
+    @Test
+    void encodeItemNoValue() {
+        assertThatIllegalArgumentException().isThrownBy(() -> new MonthCodec(TEST).encode(null))
+                .withMessage("value must not be null");
+    }
+
+    @Test
+    void encodeNull() {
+        ParameterAssert.assertThat(new MonthCodec(TEST).encodeNull())
+                .isEqualTo(new EncodedParameter(FORMAT_BINARY, INT4.getObjectId(), NULL_VALUE));
+    }
+
+    private void forEveryMonth(Consumer<Month> assertion) {
+        Arrays.stream(Month.values()).forEach(assertion);
+    }
+}