From b5a9b0991ef91ea8d692441f0dea32099089ed0c Mon Sep 17 00:00:00 2001
From: Yijie Shen <henry.yijieshen@gmail.com>
Date: Tue, 21 Sep 2021 15:32:43 +0800
Subject: [PATCH] remove buffer

---
 examples/extension.rs         |  4 ++--
 src/io/ipc/write/writer.rs    | 11 +++++------
 tests/it/io/ipc/write/file.rs |  4 ++--
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/examples/extension.rs b/examples/extension.rs
index 8462dd6c79f..e6efd061853 100644
--- a/examples/extension.rs
+++ b/examples/extension.rs
@@ -41,9 +41,9 @@ fn write_ipc<W: Write + Seek>(writer: W, array: impl Array + 'static) -> Result<
 
     let batch = RecordBatch::try_new(Arc::new(schema), vec![Arc::new(array)])?;
 
-    writer.write(&batch);
+    writer.write(&batch)?;
 
-    writer.into_inner()
+    Ok(writer.into_inner())
 }
 
 fn read_ipc(reader: &[u8]) -> Result<RecordBatch> {
diff --git a/src/io/ipc/write/writer.rs b/src/io/ipc/write/writer.rs
index 6946cb02d75..76811dc12a1 100644
--- a/src/io/ipc/write/writer.rs
+++ b/src/io/ipc/write/writer.rs
@@ -20,7 +20,7 @@
 //! The `FileWriter` and `StreamWriter` have similar interfaces,
 //! however the `FileWriter` expects a reader that supports `Seek`ing
 
-use std::io::{Error, Write, BufWriter};
+use std::io::Write;
 
 use super::super::ARROW_MAGIC;
 use super::{
@@ -39,7 +39,7 @@ use crate::record_batch::RecordBatch;
 
 pub struct FileWriter<W: Write> {
     /// The object to write to
-    writer: BufWriter<W>,
+    writer: W,
     /// IPC write options
     write_options: IpcWriteOptions,
     /// A reference to the schema, used in validating record batches
@@ -65,11 +65,10 @@ impl<W: Write> FileWriter<W> {
 
     /// Try create a new writer with IpcWriteOptions
     pub fn try_new_with_options(
-        writer: W,
+        mut writer: W,
         schema: &Schema,
         write_options: IpcWriteOptions,
     ) -> Result<Self> {
-        let mut writer = BufWriter::new(writer);
         // write magic to header
         writer.write_all(&ARROW_MAGIC[..])?;
         // create an 8-byte boundary after the header
@@ -92,8 +91,8 @@ impl<W: Write> FileWriter<W> {
         })
     }
 
-    pub fn into_inner(self) -> Result<W> {
-        self.writer.into_inner().map_err(|e| Error::from(e).into())
+    pub fn into_inner(self) -> W {
+        self.writer
     }
 
     /// Write a record batch to the file
diff --git a/tests/it/io/ipc/write/file.rs b/tests/it/io/ipc/write/file.rs
index f821d31fc35..005b51403ae 100644
--- a/tests/it/io/ipc/write/file.rs
+++ b/tests/it/io/ipc/write/file.rs
@@ -17,7 +17,7 @@ fn round_trip(batch: RecordBatch) -> Result<()> {
         let mut writer = FileWriter::try_new_with_options(result, batch.schema(), options)?;
         writer.write(&batch)?;
         writer.finish()?;
-        writer.into_inner()?
+        writer.into_inner()
     };
     let mut reader = Cursor::new(written_result);
     let metadata = read_file_metadata(&mut reader)?;
@@ -49,7 +49,7 @@ fn test_file(version: &str, file_name: &str) -> Result<()> {
             writer.write(&batch)?;
         }
         writer.finish()?;
-        writer.into_inner()?
+        writer.into_inner()
     };
     let mut reader = Cursor::new(written_result);
     let metadata = read_file_metadata(&mut reader)?;