From feb10f357d824a1bdadbed59b82403da13b42d28 Mon Sep 17 00:00:00 2001
From: Kevin Gurney <kgurney@mathworks.com>
Date: Mon, 7 Aug 2023 17:19:33 -0400
Subject: [PATCH] GH-37049: [MATLAB] Update feather `Reader` and `Writer`
 objects to work directly with `arrow.tabular.RecordBatch`s instead of MATLAB
 `table`s (#37052)

### Rationale for this change

After thinking about how to re-implement `featherread` and `featherwrite`, we realized it would be better if the `Reader` and `Writer` classes worked directly with `arrow.tabular.RecordBatch`s instead of MATLAB `table`s.

### What changes are included in this PR?

1. Updated `read` method of `arrow.internal.io.feather.Reader` to return an `arrow.tabular.RecordBatch` rather than a MATLAB `table`.
2. Updated `write` method of `arrow.internal.io.feather.Writer` to accept an `arrow.tabular.RecordBatch` rather than a MATLAB `table`.

### Are these changes tested?

Yes.

1. Updated `feather/tRoundTrip.m` to reflect the changes to the `Reader` and `Writer` classes.

### Are there any user-facing changes?

1. No

These are internal APIs.
* Closes: #37049

Authored-by: Kevin Gurney <kgurney@mathworks.com>
Signed-off-by: Kevin Gurney <kgurney@mathworks.com>
---
 .../+arrow/+internal/+io/+feather/Reader.m    |  3 +-
 .../+arrow/+internal/+io/+feather/Writer.m    |  5 ++--
 matlab/src/matlab/featherwrite.m              |  3 +-
 matlab/test/arrow/io/feather/tRoundTrip.m     | 30 +++++++++----------
 4 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/matlab/src/matlab/+arrow/+internal/+io/+feather/Reader.m b/matlab/src/matlab/+arrow/+internal/+io/+feather/Reader.m
index 80da7294d2d8d..6cd78646767a7 100644
--- a/matlab/src/matlab/+arrow/+internal/+io/+feather/Reader.m
+++ b/matlab/src/matlab/+arrow/+internal/+io/+feather/Reader.m
@@ -36,11 +36,10 @@
             obj.Proxy = arrow.internal.proxy.create("arrow.io.feather.proxy.Reader", args);
         end
 
-        function T = read(obj)
+        function recordBatch = read(obj)
             recordBatchProxyID = obj.Proxy.read();
             proxy = libmexclass.proxy.Proxy(Name="arrow.tabular.proxy.RecordBatch", ID=recordBatchProxyID);
             recordBatch = arrow.tabular.RecordBatch(proxy);
-            T = recordBatch.toMATLAB();
         end
 
         function filename = get.Filename(obj)
diff --git a/matlab/src/matlab/+arrow/+internal/+io/+feather/Writer.m b/matlab/src/matlab/+arrow/+internal/+io/+feather/Writer.m
index 37c785f10a5e3..64872ba4a023c 100644
--- a/matlab/src/matlab/+arrow/+internal/+io/+feather/Writer.m
+++ b/matlab/src/matlab/+arrow/+internal/+io/+feather/Writer.m
@@ -35,9 +35,8 @@
             obj.Proxy = arrow.internal.proxy.create(proxyName, args);
         end
 
-        function write(obj, T)
-            rb = arrow.recordbatch(T);
-            args = struct(RecordBatchProxyID=rb.Proxy.ID);
+        function write(obj, recordBatch)
+            args = struct(RecordBatchProxyID=recordBatch.Proxy.ID);
             obj.Proxy.write(args);
         end
 
diff --git a/matlab/src/matlab/featherwrite.m b/matlab/src/matlab/featherwrite.m
index cc3f45e954ad8..879edd8afc68e 100644
--- a/matlab/src/matlab/featherwrite.m
+++ b/matlab/src/matlab/featherwrite.m
@@ -28,6 +28,7 @@ function featherwrite(filename, t)
         t table
     end
 
+    recordBatch = arrow.recordbatch(t);
     writer = arrow.internal.io.feather.Writer(filename);
-    writer.write(t);
+    writer.write(recordBatch);
 end
diff --git a/matlab/test/arrow/io/feather/tRoundTrip.m b/matlab/test/arrow/io/feather/tRoundTrip.m
index e735d196c1875..f361a4543b8e4 100644
--- a/matlab/test/arrow/io/feather/tRoundTrip.m
+++ b/matlab/test/arrow/io/feather/tRoundTrip.m
@@ -31,27 +31,27 @@ function addFeatherFunctionsToMATLABPath(testCase)
     methods(Test)
         function Basic(testCase)
             import matlab.unittest.fixtures.TemporaryFolderFixture
-            
+            import arrow.internal.io.feather.*
+
             fixture = testCase.applyFixture(TemporaryFolderFixture);
             filename = fullfile(fixture.Folder, "temp.feather");
 
             DoubleVar = [10; 20; 30; 40];
             SingleVar = single([10; 15; 20; 25]);
-            tWrite = table(DoubleVar, SingleVar);
-            
-            featherwrite(tWrite, filename);
-            tRead = featherread(filename);
-            testCase.verifyEqual(tWrite, tRead);
+
+            tableWrite = table(DoubleVar, SingleVar);
+            recordBatchWrite = arrow.recordbatch(tableWrite);
+
+            writer = Writer(filename);
+            writer.write(recordBatchWrite);
+
+            reader = arrow.internal.io.feather.Reader(filename);
+            recordBatchRead = reader.read();
+
+            tableRead = table(recordBatchRead);
+
+            testCase.verifyEqual(tableWrite, tableRead);
         end
     end
-end
-
-function featherwrite(T, filename)
-    writer = arrow.internal.io.feather.Writer(filename);
-    writer.write(T);
-end
 
-function T = featherread(filename)
-    reader = arrow.internal.io.feather.Reader(filename);
-    T = reader.read();
 end
\ No newline at end of file