Allow lookup of multiple exact refs in one shot

exactRef(ref1, ref2, ref3) requests multiple specific refs in a single
lookup, which may be faster in some backends than looking them up one by
one.

firstExactRef generalizes getRef by finding the first existing ref from
the list of refs named.  Its main purpose is for the default
implementation of getRef (finding the first existing ref in a search
path).  Hopefully it can be useful for other operations that look for
refs in a search path (e.g., git log --notes=<name>), too.

Change-Id: I5c6fcf1d3920f6968b8b97f3d4c3a267258c4b86
Signed-off-by: Jonathan Nieder <jrn@google.com>

1 files changed, 42 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/RefDirectoryTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/RefDirectoryTest.java
index 292e50447e..0991598920 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/RefDirectoryTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/RefDirectoryTest.java
@@ -359,6 +359,33 @@ public class RefDirectoryTest extends LocalDiskRepositoryTestCase {
 	}
 
 	@Test
+	public void testFirstExactRef_IgnoresGarbageRef() throws IOException {
+		writeLooseRef("refs/heads/A", A);
+		write(new File(diskRepo.getDirectory(), "refs/heads/bad"), "FAIL\n");
+
+		Ref a = refdir.firstExactRef("refs/heads/bad", "refs/heads/A");
+		assertEquals("refs/heads/A", a.getName());
+		assertEquals(A, a.getObjectId());
+	}
+
+	@Test
+	public void testExactRef_IgnoresGarbageRef() throws IOException {
+		writeLooseRef("refs/heads/A", A);
+		write(new File(diskRepo.getDirectory(), "refs/heads/bad"), "FAIL\n");
+
+		Map<String, Ref> refs =
+				refdir.exactRef("refs/heads/bad", "refs/heads/A");
+
+		assertNull("no refs/heads/bad", refs.get("refs/heads/bad"));
+
+		Ref a = refs.get("refs/heads/A");
+		assertEquals("refs/heads/A", a.getName());
+		assertEquals(A, a.getObjectId());
+
+		assertEquals(1, refs.size());
+	}
+
+	@Test
 	public void testGetRefs_InvalidName() throws IOException {
 		writeLooseRef("refs/heads/A", A);
 
@@ -464,6 +491,21 @@ public class RefDirectoryTest extends LocalDiskRepositoryTestCase {
 	}
 
 	@Test
+	public void testFirstExactRef_Mixed() throws IOException {
+		writeLooseRef("refs/heads/A", A);
+		writePackedRef("refs/tags/v1.0", v1_0);
+
+		Ref a = refdir.firstExactRef("refs/heads/A", "refs/tags/v1.0");
+		Ref one = refdir.firstExactRef("refs/tags/v1.0", "refs/heads/A");
+
+		assertEquals("refs/heads/A", a.getName());
+		assertEquals("refs/tags/v1.0", one.getName());
+
+		assertEquals(A, a.getObjectId());
+		assertEquals(v1_0, one.getObjectId());
+	}
+
+	@Test
 	public void testGetRefs_TagsOnly_AllLoose() throws IOException {
 		Map<String, Ref> tags;
 		Ref a;