Fix resolving expression with ~ and ^ than extends beyond history

resolve("foo~X") where X is greater than the distance from foo to the
root should return null, but 2a2362fb introduced a bug causing it to
either return resolve("foo") or NPE. Add a test for the correct
behavior.

Also add an analogous test for foo^X where X is greater than the
number of parents (which was not broken by that commit).

Change-Id: Ic580081ece57c8c2df29b652897b425ecb34e11f

1 files changed, 23 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RepositoryResolveTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RepositoryResolveTest.java
index deb830ff5b..defd93b107 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RepositoryResolveTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RepositoryResolveTest.java
@@ -100,6 +100,15 @@ public class RepositoryResolveTest extends SampleDataRepositoryTestCase {
 	}
 
 	@Test
+	public void testObjectId_objectid_invalid_explicit_parent() throws IOException {
+		assertEquals("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1",db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4^1").name());
+		assertNull(db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4^2"));
+		assertEquals("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1",db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1^0").name());
+		assertNull(db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1^1"));
+		assertNull(db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1^2"));
+	}
+
+	@Test
 	public void testRef_refname() throws IOException {
 		assertEquals("49322bb17d3acc9146f98c97d078513228bbf3c0",db.resolve("master^0").name());
 		assertEquals("6e1475206e57110fcef4b92320436c1e9872a322",db.resolve("master^").name());
@@ -121,6 +130,20 @@ public class RepositoryResolveTest extends SampleDataRepositoryTestCase {
 	}
 
 	@Test
+	public void testDistance_past_root() throws IOException {
+		assertEquals("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1",db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4~1").name());
+		assertNull(db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4~~"));
+		assertNull(db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4~2"));
+		assertNull(db.resolve("6462e7d8024396b14d7651e2ec11e2bbf07a05c4~99"));
+		assertNull(db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1~~"));
+		assertNull(db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1~2"));
+		assertNull(db.resolve("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1~99"));
+		assertEquals("42e4e7c5e507e113ebbb7801b16b52cf867b7ce1",db.resolve("master~6").name());
+		assertNull(db.resolve("master~7"));
+		assertNull(db.resolve("master~6~"));
+	}
+
+	@Test
 	public void testTree() throws IOException {
 		assertEquals("6020a3b8d5d636e549ccbd0c53e2764684bb3125",db.resolve("49322bb17d3acc9146f98c97d078513228bbf3c0^{tree}").name());
 		assertEquals("02ba32d3649e510002c21651936b7077aa75ffa9",db.resolve("49322bb17d3acc9146f98c97d078513228bbf3c0^^{tree}").name());