ReachabilityChecker: Receive a Stream instead of a Collection

Preparatory change. Converting ObjectIds to RevCommits is potentially
expensive and in the incremental reachability check, it is probably not
required for all elements in the collection.

Pass a Stream to the reachability checker. In the follow up we make
the conversion from ObjectId to RevCommit in the stream (i.e. on
demand). This should reduce the latency of reachability checks over big
sets of references.

Change-Id: I9f310e331de5b0bf8de34143bd7dcd34316d2fba
Signed-off-by: Ivan Frade <ifrade@google.com>

1 files changed, 10 insertions, 10 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ReachabilityCheckerTestCase.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ReachabilityCheckerTestCase.java
index dd73e35727..092033449b 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ReachabilityCheckerTestCase.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ReachabilityCheckerTestCase.java
@@ -47,6 +47,7 @@ import static org.junit.Assert.assertTrue;
 
 import java.util.Arrays;
 import java.util.Optional;
+import java.util.stream.Stream;
 
 import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
@@ -83,11 +84,11 @@ public abstract class ReachabilityCheckerTestCase
 		ReachabilityChecker checker = getChecker(repo);
 
 		assertReachable("reachable from one tip",
-				checker.areAllReachable(Arrays.asList(a), Arrays.asList(c2)));
+				checker.areAllReachable(Arrays.asList(a), Stream.of(c2)));
 		assertReachable("reachable from another tip",
-				checker.areAllReachable(Arrays.asList(a), Arrays.asList(b2)));
+				checker.areAllReachable(Arrays.asList(a), Stream.of(b2)));
 		assertReachable("reachable from itself",
-				checker.areAllReachable(Arrays.asList(a), Arrays.asList(b2)));
+				checker.areAllReachable(Arrays.asList(a), Stream.of(b2)));
 	}
 
 	@Test
@@ -104,13 +105,13 @@ public abstract class ReachabilityCheckerTestCase
 
 		assertReachable("reachable through one branch",
 				checker.areAllReachable(Arrays.asList(b1),
-						Arrays.asList(merge)));
+						Stream.of(merge)));
 		assertReachable("reachable through another branch",
 				checker.areAllReachable(Arrays.asList(c1),
-						Arrays.asList(merge)));
+						Stream.of(merge)));
 		assertReachable("reachable, before the branching",
 				checker.areAllReachable(Arrays.asList(a),
-						Arrays.asList(merge)));
+						Stream.of(merge)));
 	}
 
 	@Test
@@ -123,7 +124,7 @@ public abstract class ReachabilityCheckerTestCase
 		ReachabilityChecker checker = getChecker(repo);
 
 		assertUnreachable("unreachable from the future",
-				checker.areAllReachable(Arrays.asList(b2), Arrays.asList(b1)));
+				checker.areAllReachable(Arrays.asList(b2), Stream.of(b1)));
 	}
 
 	@Test
@@ -137,7 +138,7 @@ public abstract class ReachabilityCheckerTestCase
 		ReachabilityChecker checker = getChecker(repo);
 
 		assertUnreachable("unreachable from different branch",
-				checker.areAllReachable(Arrays.asList(c1), Arrays.asList(b2)));
+				checker.areAllReachable(Arrays.asList(c1), Stream.of(b2)));
 	}
 
 	@Test
@@ -152,7 +153,7 @@ public abstract class ReachabilityCheckerTestCase
 		ReachabilityChecker checker = getChecker(repo);
 
 		assertReachable("reachable with long chain in the middle", checker
-				.areAllReachable(Arrays.asList(root), Arrays.asList(head)));
+				.areAllReachable(Arrays.asList(root), Stream.of(head)));
 	}
 
 	private static void assertReachable(String msg,
@@ -164,5 +165,4 @@ public abstract class ReachabilityCheckerTestCase
 			Optional<RevCommit> result) {
 		assertTrue(msg, result.isPresent());
 	}
-
 }