From b3a8a94a97d7f1370f534c2bbe069ff0e24b2da9 Mon Sep 17 00:00:00 2001
From: Thomas Wolf <thomas.wolf@paranor.ch>
Date: Tue, 12 Oct 2021 22:14:33 +0200
Subject: [PATCH] Fix checkout of files with mixed line endings on text=auto
 eol=crlf

Add tests for files having been checked in with mixed LF and CR-LF
line endings, and then being checked out with text or text=auto and
eol=lf or eol=crlf. These test cases were missing, and thus commit
efd1cc05 missed that AutoCRLFOutputStream needs the same detection
as AutoLFOutputStream.

Fix AutoCRLFOutputStream to not convert line endings if the blob in
the repository contains CR-LF.

Bug: 575393
Change-Id: Id0c7ae772e282097e95fddcd3f1f9d82aae31e43
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
---
 .../jgit/api/EolStreamTypeUtilTest.java       |  3 +-
 .../jgit/lib/DirCacheCheckoutTest.java        | 28 +++++++++++++++++++
 .../util/io/AutoCRLFOutputStreamTest.java     |  2 +-
 .../jgit/util/io/AutoCRLFOutputStream.java    |  3 ++
 4 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/EolStreamTypeUtilTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/EolStreamTypeUtilTest.java
index 2a553ce1a..673aa1e9c 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/EolStreamTypeUtilTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/EolStreamTypeUtilTest.java
@@ -83,7 +83,8 @@ public void testCheckoutCRLF() throws Exception {
 		testCheckout(TEXT_CRLF, AUTO_CRLF, "\r\n", "\r\n");
 		testCheckout(TEXT_CRLF, AUTO_CRLF, "\n\r", "\r\n\r");
 
-		testCheckout(TEXT_CRLF, AUTO_CRLF, "\n\r\n", "\r\n\r\n");
+		testCheckout(null, AUTO_CRLF, "\n\r\n", "\n\r\n");
+		testCheckout(TEXT_CRLF, null, "\n\r\n", "\r\n\r\n");
 		testCheckout(TEXT_CRLF, AUTO_CRLF, "\r\n\r", "\r\n\r");
 
 		testCheckout(TEXT_CRLF, AUTO_CRLF, "a\nb\n", "a\r\nb\r\n");
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
index b943486b1..af8a58f6f 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
@@ -337,6 +337,34 @@ public void testCheckoutWithLFAutoEolCrLf() throws Exception {
 				"first line\r\nsecond line\r\n", "f text=auto eol=crlf");
 	}
 
+	@Test
+	public void testCheckoutMixedAutoEolCrLf() throws Exception {
+		checkoutLineEndings("first line\nsecond line\r\n",
+				"first line\nsecond line\r\n", "f text=auto eol=crlf");
+	}
+
+	@Test
+	public void testCheckoutMixedAutoEolLf() throws Exception {
+		checkoutLineEndings("first line\nsecond line\r\n",
+				"first line\nsecond line\r\n", "f text=auto eol=lf");
+	}
+
+	@Test
+	public void testCheckoutMixedTextCrLf() throws Exception {
+		// Huh? Is this a bug in git? Both git 2.18.0 and git 2.33.0 do
+		// write the file with CRLF (and consequently report the file as
+		// modified in "git status" after check-out), however the CRLF in the
+		// repository is _not_ replaced by LF with eol=lf (see test below).
+		checkoutLineEndings("first line\nsecond line\r\n",
+				"first line\r\nsecond line\r\n", "f text eol=crlf");
+	}
+
+	@Test
+	public void testCheckoutMixedTextLf() throws Exception {
+		checkoutLineEndings("first line\nsecond line\r\nfoo",
+				"first line\nsecond line\r\nfoo", "f text eol=lf");
+	}
+
 	private DirCacheCheckout resetHard(RevCommit commit)
 			throws NoWorkTreeException,
 			CorruptObjectException, IOException {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/AutoCRLFOutputStreamTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/AutoCRLFOutputStreamTest.java
index 85ce5381f..db2f6da31 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/AutoCRLFOutputStreamTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/AutoCRLFOutputStreamTest.java
@@ -34,7 +34,7 @@ public void test() throws IOException {
 		assertNoCrLf("\r\n\r", "\n\r");
 		assertNoCrLf("\r\n\r\r", "\r\n\r\r");
 		assertNoCrLf("\r\n\r\n", "\r\n\r\n");
-		assertNoCrLf("\r\n\r\n\r", "\n\r\n\r");
+		assertNoCrLf("\n\r\n\r", "\n\r\n\r");
 		assertNoCrLf("\0\n", "\0\n");
 	}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/io/AutoCRLFOutputStream.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/io/AutoCRLFOutputStream.java
index ea6b6588c..97fe01e5d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/io/AutoCRLFOutputStream.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/io/AutoCRLFOutputStream.java
@@ -137,6 +137,9 @@ private int buffer(byte[] b, int off, int len) throws IOException {
 	private void decideMode() throws IOException {
 		if (detectBinary) {
 			isBinary = RawText.isBinary(binbuf, binbufcnt);
+			if (!isBinary) {
+				isBinary = RawText.isCrLfText(binbuf, binbufcnt);
+			}
 			detectBinary = false;
 		}
 		int cachedLen = binbufcnt;