simplify Differ api and use the new api in GitDiffCommand

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/Differ.java

@@ -15,7 +15,6 @@ import sonia.scm.util.Util;
 
 import java.io.IOException;
 import java.util.List;
-import java.util.function.Consumer;
 
 final class Differ implements AutoCloseable {
 
@@ -29,7 +28,13 @@ final class Differ implements AutoCloseable {
     this.treeWalk = treeWalk;
   }
 
-  public static Differ create(Repository repository, DiffCommandRequest request) throws IOException {
+  static Diff diff(Repository repository, DiffCommandRequest request) throws IOException {
+    try (Differ differ = create(repository, request)) {
+      return differ.diff();
+    }
+  }
+
+  private static Differ create(Repository repository, DiffCommandRequest request) throws IOException {
       RevWalk walk = new RevWalk(repository);
 
       ObjectId revision = repository.resolve(request.getRevision());
@@ -81,9 +86,9 @@ final class Differ implements AutoCloseable {
     return GitUtil.computeCommonAncestor(repository, revision1, revision2);
   }
 
-  public void process(Consumer<Diff> diffConsumer) throws IOException {
+  private Diff diff() throws IOException {
     List<DiffEntry> entries = DiffEntry.scan(treeWalk);
-    diffConsumer.accept(new Diff(commit, entries));
+    return new Diff(commit, entries);
   }
 
   @Override

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffCommand.java

@@ -34,26 +34,15 @@ package sonia.scm.repository.spi;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import com.google.common.base.Strings;
 import org.eclipse.jgit.diff.DiffEntry;
 import org.eclipse.jgit.diff.DiffFormatter;
-import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.revwalk.RevCommit;
-import org.eclipse.jgit.revwalk.RevTree;
-import org.eclipse.jgit.revwalk.RevWalk;
-import org.eclipse.jgit.treewalk.EmptyTreeIterator;
-import org.eclipse.jgit.treewalk.TreeWalk;
-import org.eclipse.jgit.treewalk.filter.PathFilter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.repository.GitUtil;
 import sonia.scm.repository.Repository;
-import sonia.scm.util.Util;
 
 import java.io.BufferedOutputStream;
-import java.io.IOException;
 import java.io.OutputStream;
-import java.util.List;
 
 /**
  *
@@ -78,7 +67,7 @@ public class GitDiffCommand extends AbstractGitCommand implements DiffCommand
    * @param context
    * @param repository
    */
-  public GitDiffCommand(GitContext context, Repository repository)
+  GitDiffCommand(GitContext context, Repository repository)
   {
     super(context, repository);
   }
@@ -95,63 +84,18 @@ public class GitDiffCommand extends AbstractGitCommand implements DiffCommand
   @Override
   public void getDiffResult(DiffCommandRequest request, OutputStream output)
   {
-    RevWalk walk = null;
-    TreeWalk treeWalk = null;
     DiffFormatter formatter = null;
 
     try
     {
-      org.eclipse.jgit.lib.Repository gr = open();
+      org.eclipse.jgit.lib.Repository repository = open();
 
-      walk = new RevWalk(gr);
-
-      ObjectId revision = gr.resolve(request.getRevision());
-      RevCommit commit = walk.parseCommit(revision);
-
-      walk.markStart(commit);
-      commit = walk.next();
-      treeWalk = new TreeWalk(gr);
-      treeWalk.reset();
-      treeWalk.setRecursive(true);
-
-      if (Util.isNotEmpty(request.getPath()))
-      {
-        treeWalk.setFilter(PathFilter.create(request.getPath()));
-      }
-
-
-      if (!Strings.isNullOrEmpty(request.getAncestorChangeset()))
-      {
-        ObjectId otherRevision = gr.resolve(request.getAncestorChangeset());
-        ObjectId ancestorId = computeCommonAncestor(gr, revision, otherRevision);
-        RevTree tree = walk.parseCommit(ancestorId).getTree();
-        treeWalk.addTree(tree);
-      }
-      else if (commit.getParentCount() > 0)
-      {
-        RevTree tree = commit.getParent(0).getTree();
-
-        if (tree != null)
-        {
-          treeWalk.addTree(tree);
-        }
-        else
-        {
-          treeWalk.addTree(new EmptyTreeIterator());
-        }
-      }
-      else
-      {
-        treeWalk.addTree(new EmptyTreeIterator());
-      }
-
-      treeWalk.addTree(commit.getTree());
       formatter = new DiffFormatter(new BufferedOutputStream(output));
-      formatter.setRepository(gr);
+      formatter.setRepository(repository);
 
-      List<DiffEntry> entries = DiffEntry.scan(treeWalk);
+      Differ.Diff diff = Differ.diff(repository, request);
 
-      for (DiffEntry e : entries)
+      for (DiffEntry e : diff.getEntries())
       {
         if (!e.getOldId().equals(e.getNewId()))
         {
@@ -168,14 +112,8 @@ public class GitDiffCommand extends AbstractGitCommand implements DiffCommand
     }
     finally
     {
-      GitUtil.release(walk);
-      GitUtil.release(treeWalk);
       GitUtil.release(formatter);
     }
   }
 
-  private ObjectId computeCommonAncestor(org.eclipse.jgit.lib.Repository repository, ObjectId revision1, ObjectId revision2) throws IOException {
-    return GitUtil.computeCommonAncestor(repository, revision1, revision2);
-  }
-
 }

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitDiffResultCommand.java

@@ -22,23 +22,16 @@ public class GitDiffResultCommand extends AbstractGitCommand implements DiffResu
 
   public DiffResult getDiffResult(DiffCommandRequest diffCommandRequest) throws IOException {
     org.eclipse.jgit.lib.Repository repository = open();
-    try (Differ differ = Differ.create(repository, diffCommandRequest)) {
+    return new GitDiffResult(repository, Differ.diff(repository, diffCommandRequest));
-      GitDiffResult result = new GitDiffResult(repository);
-      differ.process(result::process);
-      return result;
-    }
   }
 
   private class GitDiffResult implements DiffResult {
 
     private final org.eclipse.jgit.lib.Repository repository;
-    private Differ.Diff diff;
+    private final Differ.Diff diff;
 
-    private GitDiffResult(org.eclipse.jgit.lib.Repository repository) {
+    private GitDiffResult(org.eclipse.jgit.lib.Repository repository, Differ.Diff diff) {
       this.repository = repository;
-    }
-
-    void process(Differ.Diff diff) {
       this.diff = diff;
     }
 
@@ -96,7 +89,7 @@ public class GitDiffResultCommand extends AbstractGitCommand implements DiffResu
     }
 
     private String format(org.eclipse.jgit.lib.Repository repository, DiffEntry entry) {
-      try(ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
+      try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
         DiffFormatter formatter = new DiffFormatter(baos);
         formatter.setRepository(repository);
         formatter.format(entry);

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitHunkParser.java

@@ -51,6 +51,7 @@ final class GitHunkParser {
 
     FileRange oldFileRange = createFileRange(split[0]);
     // TODO merge contains two two block which starts with "-" e.g. -1,3 -2,4 +3,6
+    // check if it is relevant for our use case
     FileRange newFileRange = createFileRange(split[1]);
 
     currentGitHunk = new GitHunk(oldFileRange, newFileRange);
@@ -137,7 +138,7 @@ final class GitHunkParser {
     private final int oldLineNumber;
     private final String content;
 
-    public UnchangedGitDiffLine(int newLineNumber, int oldLineNumber, String content) {
+    private UnchangedGitDiffLine(int newLineNumber, int oldLineNumber, String content) {
       this.newLineNumber = newLineNumber;
       this.oldLineNumber = oldLineNumber;
       this.content = content;