Add restoreDefaultHistoryProvider

Author: Nathan Sobo

spec/text-buffer-spec.coffee

@@ -836,7 +836,7 @@ describe "TextBuffer", ->
       buffer.undo()
       expect(buffer.getText()).toBe('Lorem ')
 
-  describe "::getHistory(maxEntries)", ->
+  describe "::getHistory(maxEntries) and restoreDefaultHistoryProvider(history)", ->
     it "returns a base text and the state of the last `maxEntries` entries in the undo and redo stacks", ->
       buffer = new TextBuffer({text: ''})
       markerLayer = buffer.addMarkerLayer({maintainHistory: true})
@@ -859,14 +859,13 @@ describe "TextBuffer", ->
       buffer.undo()
       buffer.undo()
 
-      {baseText, nextCheckpointId, undoStack, redoStack} = buffer.getHistory(3)
-      expect(baseText).toBe('Lorem ipsum dolor ')
-      expect(nextCheckpointId).toBe(buffer.createCheckpoint())
-      expect(undoStack).toEqual([
+      history = buffer.getHistory(3)
+      expect(history.baseText).toBe('Lorem ipsum dolor ')
+      expect(history.nextCheckpointId).toBe(buffer.createCheckpoint())
+      expect(history.undoStack).toEqual([
         {
           type: 'checkpoint',
           id: checkpoint1,
-          isBarrier: false,
           markers: markersSnapshotAtCheckpoint1
         },
         {
@@ -882,7 +881,7 @@ describe "TextBuffer", ->
           markersAfter: markersSnapshotAtCheckpoint1
         }
       ])
-      expect(redoStack).toEqual([
+      expect(history.redoStack).toEqual([
         {
           type: 'transaction',
           changes: [{oldStart: Point(0, 38), oldEnd: Point(0, 38), newStart: Point(0, 38), newEnd: Point(0, 48), oldText: '', newText: 'adipiscit '}],
@@ -892,7 +891,6 @@ describe "TextBuffer", ->
         {
           type: 'checkpoint',
           id: checkpoint2,
-          isBarrier: false,
           markers: markersSnapshotAtCheckpoint2
         },
         {
@@ -903,6 +901,15 @@ describe "TextBuffer", ->
         }
       ])
 
+      buffer.createCheckpoint()
+      buffer.append('x')
+      buffer.undo()
+      buffer.clearUndoStack()
+
+      expect(buffer.getHistory()).not.toEqual(history)
+      buffer.restoreDefaultHistoryProvider(history)
+      expect(buffer.getHistory()).toEqual(history)
+
     it "throws an error when called within a transaction", ->
       buffer = new TextBuffer()
       expect(->

src/default-history-provider.coffee

@@ -1,5 +1,6 @@
 {Patch} = require 'superstring'
 MarkerLayer = require './marker-layer'
+{traversal} = require './point-helpers'
 
 SerializationVersion = 6
 
@@ -286,6 +287,21 @@ class DefaultHistoryProvider
       redoStack
     }
 
+  restoreFromSnapshot: ({@nextCheckpointId, undoStack, redoStack}) ->
+    @undoStack = undoStack.map (entry) ->
+      switch entry.type
+        when 'transaction'
+          transactionFromSnapshot(entry)
+        when 'checkpoint'
+          checkpointFromSnapshot(entry)
+
+    @redoStack = redoStack.map (entry) ->
+      switch entry.type
+        when 'transaction'
+          transactionFromSnapshot(entry)
+        when 'checkpoint'
+          checkpointFromSnapshot(entry)
+
   ###
   Section: Private
   ###
@@ -353,10 +369,12 @@ getCheckpointSnapshot = (checkpoint) ->
   {
     type: 'checkpoint',
     id: checkpoint.id,
-    isBarrier: checkpoint.isBarrier,
     markers: checkpoint.snapshot
   }
 
+checkpointFromSnapshot = ({id, markers}) ->
+  new Checkpoint(id, markers, false)
+
 getTransactionSnapshot = (transaction) ->
   {
     type: 'transaction',
@@ -365,6 +383,16 @@ getTransactionSnapshot = (transaction) ->
     markersAfter: transaction.markerSnapshotAfter
   }
 
+transactionFromSnapshot = ({changes, markersBefore, markersAfter}) ->
+  patch = new Patch
+  for {oldStart, oldEnd, oldText, newStart, newEnd, newText} in changes by -1
+    oldExtent = traversal(oldEnd, oldStart)
+    newExtent = traversal(newEnd, newStart)
+    patch.splice(oldStart, oldExtent, newExtent, oldText, newText)
+
+  # TODO: Return raw patch if there's no markersBefore && markersAfter
+  new Transaction(markersBefore, patch, markersAfter)
+
 getPatchSnapshot = (patch) ->
   changes = []
   for change in patch.getChanges() by 1

src/marker-layer.coffee

@@ -384,6 +384,7 @@ class MarkerLayer
   ###
 
   addMarker: (id, range, params) ->
+    range = Range.fromObject(range)
     Point.assertValid(range.start)
     Point.assertValid(range.end)
     @index.insert(id, range.start, range.end)

src/marker.coffee

@@ -343,6 +343,9 @@ class Marker
   update: (oldRange, {range, reversed, tailed, valid, exclusive, properties}, textChanged=false, suppressMarkerLayerUpdateEvents=false) ->
     return if @isDestroyed()
 
+    oldRange = Range.fromObject(oldRange)
+    range = Range.fromObject(range) if range?
+
     wasExclusive = @isExclusive()
     updated = propertiesChanged = false
 

src/text-buffer.coffee

@@ -1122,6 +1122,11 @@ class TextBuffer
   setHistoryProvider: (historyProvider) ->
     @historyProvider = historyProvider
 
+  restoreDefaultHistoryProvider: (history) ->
+    provider = new DefaultHistoryProvider(this)
+    provider.restoreFromSnapshot(history)
+    @setHistoryProvider(provider)
+
   getHistory: (maxEntries) ->
     if @transactCallDepth > 0
       throw new Error('Cannot build history snapshots within transactions')