Fix bug: unnecessary read of data content - corrupt output

Author: psolomin

vertx-pg-client/src/main/java/io/vertx/pgclient/impl/codec/CopyOutCommand.java

@@ -22,6 +22,7 @@ public CopyOutCommand(
     this.resultHandler = resultHandler;
     this.collector = Collector.of(
       Buffer::buffer,
+      // TODO: this might be unnecessary slow - think of alternatives
       (v, chunk) -> v.appendBuffer(Buffer.buffer(chunk)),
       (v1, v2) -> null,
       (finalResult) -> finalResult

vertx-pg-client/src/main/java/io/vertx/pgclient/impl/codec/CopyOutDataDecoder.java

@@ -24,7 +24,7 @@ public int size() {
     return size;
   }
 
-  public void handleChunk(int len, ByteBuf in) {
+  public void handleChunk(ByteBuf in) {
     if (failure != null) {
       return;
     }

vertx-pg-client/src/main/java/io/vertx/pgclient/impl/codec/PgDecoder.java

@@ -475,8 +475,7 @@ private void decodeCopyOutResponse(ChannelHandlerContext ctx, ByteBuf in) {}
   private void decodeCopyData(ChannelHandlerContext ctx, ByteBuf in) {
     PgCommandCodec<?, ?> codec = inflight.peek();
     CopyOutCommandCodec cmdCodec = (CopyOutCommandCodec) codec;
-    int len = in.readUnsignedShort();
-    cmdCodec.decoder.handleChunk(len, in);
+    cmdCodec.decoder.handleChunk(in);
   }
 
   private void decodeCopyCompletion(ChannelHandlerContext ctx, ByteBuf in) {}

vertx-pg-client/src/test/java/io/vertx/pgclient/PgConnectionCopyTest.java

@@ -50,16 +50,16 @@ public void testCopyToCsvBytes(TestContext ctx) {
               ctx.assertEquals(10, result.size());
               ctx.assertEquals(
                 Buffer.buffer(
-                  "Whatever-0\n" +
-                  "Whatever-1\n" +
-                  "Whatever-2\n" +
-                  "Whatever-3\n" +
-                  "Whatever-4\n" +
-                  "Whatever-5\n" +
-                  "Whatever-6\n" +
-                  "Whatever-7\n" +
-                  "Whatever-8\n" +
-                  "Whatever-9\n"
+                  "0,Whatever-0\n" +
+                  "1,Whatever-1\n" +
+                  "2,Whatever-2\n" +
+                  "3,Whatever-3\n" +
+                  "4,Whatever-4\n" +
+                  "5,Whatever-5\n" +
+                  "6,Whatever-6\n" +
+                  "7,Whatever-7\n" +
+                  "8,Whatever-8\n" +
+                  "9,Whatever-9\n"
                 ),
                 result.value()
               );