added resetIndex() to RepositoryTestCase

Added a utility method to set the reset an index to match exactly
some content in the filesystem. This can be used by tests to prepare
commits in the working-tree and set the index in one shot.

[sp: Cleaned up formatting, added getEntryFile(), released inserter.]

Change-Id: If38b1f7cacaaf769f51b14541c5da0c1e24568a5
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RacyGitTests.java

@@ -43,13 +43,10 @@
 package org.eclipse.jgit.lib;
 
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.TreeSet;
 
-import org.eclipse.jgit.dircache.DirCacheBuilder;
-import org.eclipse.jgit.dircache.DirCacheEntry;
 import org.eclipse.jgit.treewalk.FileTreeIterator;
 import org.eclipse.jgit.treewalk.FileTreeIteratorWithTimeControl;
 import org.eclipse.jgit.treewalk.NameConflictTreeWalk;
@@ -133,7 +130,7 @@ public void testRacyGitDetection() throws IOException,
 		modTimes.add(fsTick(lastFile));
 
 		// now add both files to the index. No racy git expected
-		addToIndex(modTimes);
+		resetIndex(new FileTreeIteratorWithTimeControl(db, modTimes));
 
 		assertEquals(
 				"[a, mode:100644, time:t0, length:1, sha1:2e65efe2a145dda7ee51d1741299f848e5bf752e]" +
@@ -150,7 +147,7 @@ public void testRacyGitDetection() throws IOException,
 		// now update the index the index. 'a' has to be racily clean -- because
 		// it's modification time is exactly the same as the previous index file
 		// mod time.
-		addToIndex(modTimes);
+		resetIndex(new FileTreeIteratorWithTimeControl(db, modTimes));
 
 		db.readDirCache();
 		// although racily clean a should not be reported as being dirty
@@ -160,24 +157,6 @@ public void testRacyGitDetection() throws IOException,
 				indexState(SMUDGE|MOD_TIME|LENGTH));
 	}
 
-	private void addToIndex(TreeSet<Long> modTimes)
-			throws FileNotFoundException, IOException {
-		DirCacheBuilder builder = db.lockDirCache().builder();
-		FileTreeIterator fIt = new FileTreeIteratorWithTimeControl(
-				db, modTimes);
-		DirCacheEntry dce;
-		while (!fIt.eof()) {
-			dce = new DirCacheEntry(fIt.getEntryPathString());
-			dce.setFileMode(fIt.getEntryFileMode());
-			dce.setLastModified(fIt.getEntryLastModified());
-			dce.setLength((int) fIt.getEntryLength());
-			dce.setObjectId(fIt.getEntryObjectId());
-			builder.add(dce);
-			fIt.next(1);
-		}
-		builder.commit();
-	}
-
 	private File addToWorkDir(String path, String content) throws IOException {
 		File f = new File(db.getWorkTree(), path);
 		FileOutputStream fos = new FileOutputStream(f);

org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RepositoryTestCase.java

@@ -48,6 +48,7 @@
 
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
@@ -56,9 +57,12 @@
 import java.util.TreeSet;
 
 import org.eclipse.jgit.dircache.DirCache;
+import org.eclipse.jgit.dircache.DirCacheBuilder;
+import org.eclipse.jgit.dircache.DirCacheEntry;
 import org.eclipse.jgit.dircache.DirCacheIterator;
 import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
 import org.eclipse.jgit.storage.file.FileRepository;
+import org.eclipse.jgit.treewalk.FileTreeIterator;
 import org.eclipse.jgit.treewalk.NameConflictTreeWalk;
 
 /**
@@ -202,6 +206,46 @@ public String indexState(int includedOptions)
 		return sb.toString();
 	}
 
+	/**
+	 * Resets the index to represent exactly some filesystem content. E.g. the
+	 * following call will replace the index with the working tree content:
+	 * <p>
+	 * <code>resetIndex(new FileSystemIterator(db))</code>
+	 * <p>
+	 * This method can be used by testcases which first prepare a new commit
+	 * somewhere in the filesystem (e.g. in the working-tree) and then want to
+	 * have an index which matches their prepared content.
+	 *
+	 * @param treeItr
+	 *            a {@link FileTreeIterator} which determines which files should
+	 *            go into the new index
+	 * @throws FileNotFoundException
+	 * @throws IOException
+	 */
+	protected void resetIndex(FileTreeIterator treeItr)
+			throws FileNotFoundException, IOException {
+		ObjectInserter inserter = db.newObjectInserter();
+		DirCacheBuilder builder = db.lockDirCache().builder();
+		DirCacheEntry dce;
+
+		while (!treeItr.eof()) {
+			long len = treeItr.getEntryLength();
+
+			dce = new DirCacheEntry(treeItr.getEntryPathString());
+			dce.setFileMode(treeItr.getEntryFileMode());
+			dce.setLastModified(treeItr.getEntryLastModified());
+			dce.setLength((int) len);
+			FileInputStream in = new FileInputStream(treeItr.getEntryFile());
+			dce.setObjectId(inserter.insert(Constants.OBJ_BLOB, len, in));
+			in.close();
+			builder.add(dce);
+			treeItr.next(1);
+		}
+		builder.commit();
+		inserter.flush();
+		inserter.release();
+	}
+
 	/**
 	 * Helper method to map arbitrary objects to user-defined names. This can be
 	 * used create short names for objects to produce small and stable debug

org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java

@@ -211,4 +211,13 @@ public File getFile() {
 	public File getDirectory() {
 		return directory;
 	}
+
+	/**
+	 * @return The location of the working file. This is the same as {@code new
+	 *         File(getDirectory(), getEntryPath())} but may be faster by
+	 *         reusing an internal File instance.
+	 */
+	public File getEntryFile() {
+		return ((FileEntry) current()).getFile();
+	}
 }