Take core.autocrlf into account for blame annotations

Blaming with core.autocrlf set to 'true' - even for freshly checked out
files - showed all lines as being locally modified. For autocrlf = true
the line breaks of the local file will be converted to LF for blaming.
This results in useful diffs and therefor in the desired blame
annotations.

For autocrlf = input no conversion takes place to cope with CRLF line
breaks in the repository, in addition to the usual LF. For autocrlf =
true CRLF line breaks in the repo can't be supported without additional
effort. In that case the whole local file will be blamed as being
locally modified.

Change-Id: If020dcca54d16b2fb79210a070b8480aec82e58e
Signed-off-by: Konrad Kügler <swamblumat-eclipsebugs@yahoo.de>
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/api/BlameCommandTest.java

@@ -45,9 +45,15 @@ package org.eclipse.jgit.api;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 
+import java.io.File;
+
+import org.eclipse.jgit.api.ResetCommand.ResetType;
 import org.eclipse.jgit.blame.BlameResult;
 import org.eclipse.jgit.junit.RepositoryTestCase;
+import org.eclipse.jgit.lib.ConfigConstants;
+import org.eclipse.jgit.lib.CoreConfig.AutoCRLF;
 import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.storage.file.FileBasedConfig;
 import org.junit.Test;
 
 /**
@@ -325,4 +331,59 @@ public class BlameCommandTest extends RepositoryTestCase {
 		assertEquals(commit3, lines.getSourceCommit(1));
 		assertEquals(commit3, lines.getSourceCommit(2));
 	}
+
+	@Test
+	public void testCoreAutoCrlf1() throws Exception {
+		testCoreAutoCrlf(AutoCRLF.INPUT, AutoCRLF.FALSE);
+	}
+
+	@Test
+	public void testCoreAutoCrlf2() throws Exception {
+		testCoreAutoCrlf(AutoCRLF.FALSE, AutoCRLF.FALSE);
+	}
+
+	@Test
+	public void testCoreAutoCrlf3() throws Exception {
+		testCoreAutoCrlf(AutoCRLF.INPUT, AutoCRLF.INPUT);
+	}
+
+	@Test
+	public void testCoreAutoCrlf4() throws Exception {
+		testCoreAutoCrlf(AutoCRLF.FALSE, AutoCRLF.INPUT);
+	}
+
+	@Test
+	public void testCoreAutoCrlf5() throws Exception {
+		testCoreAutoCrlf(AutoCRLF.INPUT, AutoCRLF.TRUE);
+	}
+
+	private void testCoreAutoCrlf(AutoCRLF modeForCommitting,
+			AutoCRLF modeForReset) throws Exception {
+		Git git = new Git(db);
+		FileBasedConfig config = db.getConfig();
+		config.setEnum(ConfigConstants.CONFIG_CORE_SECTION, null,
+				ConfigConstants.CONFIG_KEY_AUTOCRLF, modeForCommitting);
+		config.save();
+
+		String joinedCrlf = "a\r\nb\r\nc\r\n";
+		File trashFile = writeTrashFile("file.txt", joinedCrlf);
+		git.add().addFilepattern("file.txt").call();
+		RevCommit commit = git.commit().setMessage("create file").call();
+
+		// re-create file from the repo
+		trashFile.delete();
+		config.setEnum(ConfigConstants.CONFIG_CORE_SECTION, null,
+				ConfigConstants.CONFIG_KEY_AUTOCRLF, modeForReset);
+		config.save();
+		git.reset().setMode(ResetType.HARD).call();
+
+		BlameCommand command = new BlameCommand(db);
+		command.setFilePath("file.txt");
+		BlameResult lines = command.call();
+
+		assertEquals(3, lines.getResultContents().size());
+		assertEquals(commit, lines.getSourceCommit(0));
+		assertEquals(commit, lines.getSourceCommit(1));
+		assertEquals(commit, lines.getSourceCommit(2));
+	}
 }

org.eclipse.jgit/src/org/eclipse/jgit/api/BlameCommand.java

@@ -43,7 +43,10 @@
 package org.eclipse.jgit.api;
 
 import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -60,6 +63,10 @@ import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.lib.CoreConfig.AutoCRLF;
+import org.eclipse.jgit.treewalk.WorkingTreeOptions;
+import org.eclipse.jgit.util.IO;
+import org.eclipse.jgit.util.io.EolCanonicalizingInputStream;
 
 /**
  * Blame command for building a {@link BlameResult} for a file path.
@@ -215,8 +222,10 @@ public class BlameCommand extends GitCommand<BlameResult> {
 						gen.push(null, dc.getEntry(entry).getObjectId());
 
 					File inTree = new File(repo.getWorkTree(), path);
-					if (repo.getFS().isFile(inTree))
-						gen.push(null, new RawText(inTree));
+					if (repo.getFS().isFile(inTree)) {
+						RawText rawText = getRawText(inTree);
+						gen.push(null, rawText);
+					}
 				}
 			}
 			return gen.computeBlameResult();
@@ -226,4 +235,49 @@ public class BlameCommand extends GitCommand<BlameResult> {
 			gen.release();
 		}
 	}
+
+	private RawText getRawText(File inTree) throws IOException,
+			FileNotFoundException {
+		RawText rawText;
+
+		WorkingTreeOptions workingTreeOptions = getRepository().getConfig()
+				.get(WorkingTreeOptions.KEY);
+		AutoCRLF autoCRLF = workingTreeOptions.getAutoCRLF();
+		switch (autoCRLF) {
+		case FALSE:
+		case INPUT:
+			// Git used the repo format on checkout, but other tools
+			// may change the format to CRLF. We ignore that here.
+			rawText = new RawText(inTree);
+			break;
+		case TRUE:
+			EolCanonicalizingInputStream in = new EolCanonicalizingInputStream(
+					new FileInputStream(inTree), true);
+			// Canonicalization should lead to same or shorter length
+			// (CRLF to LF), so the file size on disk is an upper size bound
+			rawText = new RawText(toByteArray(in, (int) inTree.length()));
+			break;
+		default:
+			throw new IllegalArgumentException(
+					"Unknown autocrlf option " + autoCRLF); //$NON-NLS-1$
+		}
+		return rawText;
+	}
+
+	private static byte[] toByteArray(InputStream source, int upperSizeLimit)
+			throws IOException {
+		byte[] buffer = new byte[upperSizeLimit];
+		try {
+			int read = IO.readFully(source, buffer, 0);
+			if (read == upperSizeLimit)
+				return buffer;
+			else {
+				byte[] copy = new byte[read];
+				System.arraycopy(buffer, 0, copy, 0, read);
+				return copy;
+			}
+		} finally {
+			source.close();
+		}
+	}
 }