Use w1 for hashCode of AbbreviatedObjectId
Very short abbreviations that are under 8 hex digits do not
have values in w2. Use w1 as the Java hashCode() instead, so
that the prefix of the abbreviation is always included in the
hashing function used by any java.util.Collection type.
Change-Id: Idaf69f86b62630ba4a022d31b4c293c6d138f557
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/AbbreviatedObjectIdTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/AbbreviatedObjectIdTest.java
index 6529d9e..30a9626 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/AbbreviatedObjectIdTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/AbbreviatedObjectIdTest.java
@@ -86,7 +86,6 @@
final ObjectId f = i.toObjectId();
assertNotNull(f);
assertEquals(ObjectId.fromString(s), f);
- assertEquals(f.hashCode(), i.hashCode());
}
@Test
@@ -101,7 +100,6 @@
final ObjectId f = i.toObjectId();
assertNotNull(f);
assertEquals(ObjectId.fromString(s), f);
- assertEquals(f.hashCode(), i.hashCode());
}
@Test
@@ -215,7 +213,7 @@
}
@Test
- public void testEquals_Short() {
+ public void testEquals_Short8() {
final String s = "7b6e8067";
final AbbreviatedObjectId a = AbbreviatedObjectId.fromString(s);
final AbbreviatedObjectId b = AbbreviatedObjectId.fromString(s);
@@ -226,6 +224,18 @@
}
@Test
+ public void testEquals_Short4() {
+ final String s = "7b6e";
+ final AbbreviatedObjectId a = AbbreviatedObjectId.fromString(s);
+ final AbbreviatedObjectId b = AbbreviatedObjectId.fromString(s);
+ assertNotSame(a, b);
+ assertTrue(a.hashCode() != 0);
+ assertTrue(a.hashCode() == b.hashCode());
+ assertEquals(b, a);
+ assertEquals(a, b);
+ }
+
+ @Test
public void testEquals_Full() {
final String s = "7b6e8067ec96acef9a4184b43210d583b6d2f99a";
final AbbreviatedObjectId a = AbbreviatedObjectId.fromString(s);
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/AbbreviatedObjectId.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/AbbreviatedObjectId.java
index 29a379e..0567051 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/AbbreviatedObjectId.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/AbbreviatedObjectId.java
@@ -336,7 +336,7 @@
@Override
public int hashCode() {
- return w2;
+ return w1;
}
@Override
