MergedReftableTest#scanDuplicates tests whether we can write duplicate keys in a merged reftable. Apparently, the first key appearing should get precedence, and this works because the sort() algorithm on ordered collections is stable. This is potentially confusing behavior, because you can write data into the table that cannot be retrieved (Merged table can only have one entry per key), and the APIs such as exactRef() only return a single value. Make this consistent with behavior introduced in I04f55c481 "reftable: enforce ordering for ref and log writes" by considering a duplicate key in sortAndWriteRefs as a fatal runtime error. Change-Id: I1eedd18f028180069f78c5c467169dcfe1521157 Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>tags/v5.6.0.201911271000-m3
[ref-fmt]: https://git-scm.com/docs/git-check-ref-format | [ref-fmt]: https://git-scm.com/docs/git-check-ref-format | ||||
### Key unicity | |||||
Each entry must have a unique key; repeated keys are disallowed. | |||||
### Network byte order | ### Network byte order | ||||
All multi-byte, fixed width fields are in network byte order. | All multi-byte, fixed width fields are in network byte order. |
} | } | ||||
} | } | ||||
@Test | |||||
public void scanDuplicates() throws IOException { | |||||
List<Ref> delta1 = Arrays.asList( | |||||
ref("refs/heads/apple", 1), | |||||
ref("refs/heads/banana", 2)); | |||||
List<Ref> delta2 = Arrays.asList( | |||||
ref("refs/heads/apple", 3), | |||||
ref("refs/heads/apple", 4)); | |||||
MergedReftable mr = merge(write(delta1, 1000), write(delta2, 2000)); | |||||
try (RefCursor rc = mr.allRefs()) { | |||||
assertTrue(rc.next()); | |||||
assertEquals("refs/heads/apple", rc.getRef().getName()); | |||||
assertEquals(id(3), rc.getRef().getObjectId()); | |||||
assertEquals(2000, rc.getRef().getUpdateIndex()); | |||||
assertTrue(rc.next()); | |||||
assertEquals("refs/heads/banana", rc.getRef().getName()); | |||||
assertEquals(id(2), rc.getRef().getObjectId()); | |||||
assertEquals(1000, rc.getRef().getUpdateIndex()); | |||||
assertFalse(rc.next()); | |||||
} | |||||
} | |||||
@Test | @Test | ||||
public void scanIncludeDeletes() throws IOException { | public void scanIncludeDeletes() throws IOException { | ||||
List<Ref> delta1 = Arrays.asList(ref("refs/heads/next", 4)); | List<Ref> delta1 = Arrays.asList(ref("refs/heads/next", 4)); |
} | } | ||||
@Test | @Test | ||||
public void invalidRefWriteOrder() throws IOException { | |||||
public void invalidRefWriteOrderSortAndWrite() { | |||||
Ref master = ref(MASTER, 1); | Ref master = ref(MASTER, 1); | ||||
Ref next = ref(NEXT, 2); | |||||
ReftableWriter writer = new ReftableWriter(new ByteArrayOutputStream()) | ReftableWriter writer = new ReftableWriter(new ByteArrayOutputStream()) | ||||
.setMinUpdateIndex(1) | .setMinUpdateIndex(1) | ||||
.setMaxUpdateIndex(1) | .setMaxUpdateIndex(1) | ||||
.begin(); | .begin(); | ||||
writer.writeRef(next); | |||||
List<Ref> refs = new ArrayList<>(); | |||||
refs.add(master); | |||||
refs.add(master); | |||||
IllegalArgumentException e = assertThrows( | IllegalArgumentException e = assertThrows( | ||||
IllegalArgumentException.class, | IllegalArgumentException.class, | ||||
() -> writer.writeRef(master)); | |||||
() -> writer.sortAndWriteRefs(refs)); | |||||
assertThat(e.getMessage(), containsString("records must be increasing")); | assertThat(e.getMessage(), containsString("records must be increasing")); | ||||
} | } | ||||
/** | /** | ||||
* Sort a collection of references and write them to the reftable. | * Sort a collection of references and write them to the reftable. | ||||
* The input refs may not have duplicate names. | |||||
* | * | ||||
* @param refsToPack | * @param refsToPack | ||||
* references to sort and write. | * references to sort and write. | ||||
.map(r -> new RefEntry(r, maxUpdateIndex - minUpdateIndex)) | .map(r -> new RefEntry(r, maxUpdateIndex - minUpdateIndex)) | ||||
.sorted(Entry::compare) | .sorted(Entry::compare) | ||||
.iterator(); | .iterator(); | ||||
RefEntry last = null; | |||||
while (itr.hasNext()) { | while (itr.hasNext()) { | ||||
RefEntry entry = itr.next(); | RefEntry entry = itr.next(); | ||||
if (last != null && Entry.compare(last, entry) == 0) { | |||||
throwIllegalEntry(last, entry); | |||||
} | |||||
long blockPos = refs.write(entry); | long blockPos = refs.write(entry); | ||||
indexRef(entry.ref, blockPos); | indexRef(entry.ref, blockPos); | ||||
last = entry; | |||||
} | } | ||||
return this; | return this; | ||||
} | } |