From d8868c47e14444e3a60759a40037b02c761170f1 Mon Sep 17 00:00:00 2001
From: Kevin Jahns <kevin.jahns@pm.me>
Date: Wed, 16 Dec 2020 23:45:28 +0100
Subject: [PATCH] test case for deletes + fix

---
 src/utils/updates.js   |  7 ++++--
 tests/updates.tests.js | 55 ++++++++++++++++++++++++++++++------------
 2 files changed, 45 insertions(+), 17 deletions(-)

diff --git a/src/utils/updates.js b/src/utils/updates.js
index 4c524d45..ce46fa5d 100644
--- a/src/utils/updates.js
+++ b/src/utils/updates.js
@@ -96,11 +96,14 @@ export const logUpdate = update => logUpdateV2(update, UpdateDecoderV1)
  */
 export const logUpdateV2 = (update, YDecoder = UpdateDecoderV2) => {
   const structs = []
-  const lazyDecoder = new LazyStructReader(new YDecoder(decoding.createDecoder(update)))
+  const updateDecoder = new YDecoder(decoding.createDecoder(update))
+  const lazyDecoder = new LazyStructReader(updateDecoder)
   for (let curr = lazyDecoder.curr; curr !== null; curr = lazyDecoder.next()) {
     structs.push(curr)
   }
-  logging.print(structs)
+  logging.print('Structs: ', structs)
+  const ds = readDeleteSet(updateDecoder)
+  logging.print('DeleteSet: ', ds)
 }
 
 export class LazyStructWriter {
diff --git a/tests/updates.tests.js b/tests/updates.tests.js
index e91401b7..dfa08420 100644
--- a/tests/updates.tests.js
+++ b/tests/updates.tests.js
@@ -37,19 +37,10 @@ export const testMergeUpdates = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {Y.Doc} ydoc
+ * @param {Array<Uint8Array>} updates - expecting at least 4 updates
  */
-export const testMergeUpdatesWrongOrder = tc => {
-  const ydoc = new Y.Doc()
-  const updates = /** @type {Array<Uint8Array>} */ ([])
-  ydoc.on(updateEventName, update => { updates.push(update) })
-
-  const array = ydoc.getArray()
-  array.insert(0, [1])
-  array.insert(0, [2])
-  array.insert(0, [3])
-  array.insert(0, [4])
-
+const checkUpdateCases = (ydoc, updates) => {
   const cases = []
 
   // Case 1: Simple case, simply merge everything
@@ -71,7 +62,8 @@ export const testMergeUpdatesWrongOrder = tc => {
   // Case 4: Separated updates (containing skips)
   cases.push(mergeUpdates([
     mergeUpdates([updates[0], updates[2]]),
-    mergeUpdates([updates[1], updates[3]])
+    mergeUpdates([updates[1], updates[3]]),
+    mergeUpdates(updates.slice(4))
   ]))
 
   // Case 5: overlapping with many duplicates
@@ -86,11 +78,44 @@ export const testMergeUpdatesWrongOrder = tc => {
     logUpdate(updates)
     const merged = new Y.Doc()
     applyUpdate(merged, updates)
-    t.compareArrays(merged.getArray().toArray(), array.toArray())
-    t.compare(updates, targetState)
+    t.compareArrays(merged.getArray().toArray(), ydoc.getArray().toArray())
   })
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testMergeUpdates1 = tc => {
+  const ydoc = new Y.Doc({ gc: false })
+  const updates = /** @type {Array<Uint8Array>} */ ([])
+  ydoc.on(updateEventName, update => { updates.push(update) })
+
+  const array = ydoc.getArray()
+  array.insert(0, [1])
+  array.insert(0, [2])
+  array.insert(0, [3])
+  array.insert(0, [4])
+
+  checkUpdateCases(ydoc, updates)
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testMergeUpdates2 = tc => {
+  const ydoc = new Y.Doc({ gc: false })
+  const updates = /** @type {Array<Uint8Array>} */ ([])
+  ydoc.on(updateEventName, update => { updates.push(update) })
+
+  const array = ydoc.getArray()
+  array.insert(0, [1, 2])
+  array.delete(1, 1)
+  array.insert(0, [3, 4])
+  array.delete(1, 2)
+
+  checkUpdateCases(ydoc, updates)
+}
+
 /**
  * @todo be able to apply Skip structs to Yjs docs
  */