From cbee87fa0c17880f7234092499edc2be709ff5f2 Mon Sep 17 00:00:00 2001
From: Rene Pfeuffer <rene.pfeuffer@cloudogu.com>
Date: Mon, 18 Nov 2019 11:41:09 +0100
Subject: [PATCH] Buffer output and do not create new temp array streams

---
 .../scm/repository/spi/GitDiffCommand.java    | 53 +++++++++++--------
 ...itDiffCommand_DequoteOutputStreamTest.java | 35 ++++++++++++
 2 files changed, 65 insertions(+), 23 deletions(-)
 create mode 100644 scm-plugins/scm-git-plugin/src/test/java/sonia/scm/repository/spi/GitDiffCommand_DequoteOutputStreamTest.java

diff --git a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffCommand.java b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffCommand.java
index 0fbe45d3cd..c165ee550e 100644
--- a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffCommand.java
+++ b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffCommand.java
@@ -37,10 +37,13 @@ import org.eclipse.jgit.util.QuotedString;
 import sonia.scm.repository.Repository;
 import sonia.scm.repository.api.DiffCommandBuilder;
 
+import java.io.BufferedOutputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+
 /**
  *
  * @author Sebastian Sdorra
@@ -73,17 +76,19 @@ public class GitDiffCommand extends AbstractGitCommand implements DiffCommand {
     };
   }
 
-  private static class DequoteOutputStream extends OutputStream {
+  static class DequoteOutputStream extends OutputStream {
 
     private final OutputStream target;
 
     private boolean afterNL = false;
+    private boolean writeToBuffer = false;
     private int minusCount = 0;
     private int plusCount = 0;
-    private ByteArrayOutputStream buffer;
 
-    private DequoteOutputStream(OutputStream target) {
-      this.target = target;
+    private final ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+
+    DequoteOutputStream(OutputStream target) {
+      this.target = new BufferedOutputStream(target);
     }
 
     @Override
@@ -105,38 +110,40 @@ public class GitDiffCommand extends AbstractGitCommand implements DiffCommand {
         afterNL = false;
         target.write(i);
       } else if (i == (int) ' ' && plusCount == 3) {
-        buffer = new ByteArrayOutputStream();
+        writeToBuffer = true;
+        buffer.reset();
         afterNL = false;
         plusCount = 0;
         target.write(i);
       } else if (i == (int) ' ' && minusCount == 3) {
         minusCount = 0;
         afterNL = false;
-        buffer = new ByteArrayOutputStream();
+        writeToBuffer = true;
+        buffer.reset();
         target.write(i);
       } else if (i == (int) '\n') {
-        if (buffer != null) {
-          afterNL = true;
+        afterNL = true;
+        if (writeToBuffer) {
           byte[] bytes = buffer.toByteArray();
           String dequote = QuotedString.GIT_PATH.dequote(bytes, 0, bytes.length);
-          target.write(dequote.getBytes());
-          target.write(i);
-          buffer = null;
-        } else {
-          afterNL = true;
-          target.write(i);
+          target.write(dequote.getBytes(UTF_8));
+          writeToBuffer  = false;
         }
+        target.write(i);
+      } else if (writeToBuffer) {
+        buffer.write(i);
+        afterNL = false;
       } else {
-        if (buffer != null) {
-          buffer.write(i);
-          afterNL = false;
-        } else {
-          target.write(i);
-          afterNL = false;
-          minusCount = 0;
-          plusCount = 0;
-        }
+        target.write(i);
+        afterNL = false;
+        minusCount = 0;
+        plusCount = 0;
       }
     }
+
+    @Override
+    public void flush() throws IOException {
+      target.flush();
+    }
   }
 }
diff --git a/scm-plugins/scm-git-plugin/src/test/java/sonia/scm/repository/spi/GitDiffCommand_DequoteOutputStreamTest.java b/scm-plugins/scm-git-plugin/src/test/java/sonia/scm/repository/spi/GitDiffCommand_DequoteOutputStreamTest.java
new file mode 100644
index 0000000000..790bb34b4e
--- /dev/null
+++ b/scm-plugins/scm-git-plugin/src/test/java/sonia/scm/repository/spi/GitDiffCommand_DequoteOutputStreamTest.java
@@ -0,0 +1,35 @@
+package sonia.scm.repository.spi;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+public class GitDiffCommand_DequoteOutputStreamTest {
+
+  @Test
+  void shouldDequoteText() throws IOException {
+    String s = "diff --git \"a/\\303\\272\\303\\274\\303\\276\\303\\253\\303\\251\\303\\245\\303\\253\\303\\245\\303\\251 \\303\\245g\\303\\260f\\303\\237\" \"b/\\303\\272\\303\\274\\303\\276\\303\\253\\303\\251\\303\\245\\303\\253\\303\\245\\303\\251 \\303\\245g\\303\\260f\\303\\237\"\n" +
+      "new file mode 100644\n" +
+      "index 0000000..8cb0607\n" +
+      "--- /dev/null\n" +
+      "+++ \"b/\\303\\272\\303\\274\\303\\276\\303\\253\\303\\251\\303\\245\\303\\253\\303\\245\\303\\251 \\303\\245g\\303\\260f\\303\\237\"\n" +
+      "@@ -0,0 +1 @@\n" +
+      "+rthms";
+
+    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+    GitDiffCommand.DequoteOutputStream stream = new GitDiffCommand.DequoteOutputStream(buffer);
+    byte[] bytes = s.getBytes();
+    stream.write(bytes, 0, bytes.length);
+    stream.flush();
+
+    Assertions.assertThat(buffer.toString()).isEqualTo("diff --git \"a/\\303\\272\\303\\274\\303\\276\\303\\253\\303\\251\\303\\245\\303\\253\\303\\245\\303\\251 \\303\\245g\\303\\260f\\303\\237\" \"b/\\303\\272\\303\\274\\303\\276\\303\\253\\303\\251\\303\\245\\303\\253\\303\\245\\303\\251 \\303\\245g\\303\\260f\\303\\237\"\n" +
+      "new file mode 100644\n" +
+      "index 0000000..8cb0607\n" +
+      "--- /dev/null\n" +
+      "+++ b/úüþëéåëåé ågðfß\n" +
+      "@@ -0,0 +1 @@\n" +
+      "+rthms");
+  }
+}