Add in new comment op type

services/document-updater/app/coffee/sharejs/types/text.coffee

@@ -31,7 +31,8 @@ checkValidComponent = (c) ->
 
   i_type = typeof c.i
   d_type = typeof c.d
-  throw new Error 'component needs an i or d field' unless (i_type == 'string') ^ (d_type == 'string')
+  c_type = typeof c.c
+  throw new Error 'component needs an i, d or c field' unless (i_type == 'string') ^ (d_type == 'string') ^ (c_type == 'string')
 
   throw new Error 'position cannot be negative' unless c.p >= 0
 
@@ -44,11 +45,15 @@ text.apply = (snapshot, op) ->
   for component in op
     if component.i?
       snapshot = strInject snapshot, component.p, component.i
-    else
+    else if component.d?
       deleted = snapshot[component.p...(component.p + component.d.length)]
       throw new Error "Delete component '#{component.d}' does not match deleted text '#{deleted}'" unless component.d == deleted
       snapshot = snapshot[...component.p] + snapshot[(component.p + component.d.length)..]
-  
+    else if component.c?
+      comment = snapshot[component.p...(component.p + component.c.length)]
+      throw new Error "Comment component '#{component.c}' does not match commented text '#{comment}'" unless component.c == comment
+    else
+      throw new Error "Unknown op type"
   snapshot
 
 
@@ -112,7 +117,7 @@ transformPosition = (pos, c, insertAfter) ->
       pos + c.i.length
     else
       pos
-  else
+  else if c.d?
     # I think this could also be written as: Math.min(c.p, Math.min(c.p - otherC.p, otherC.d.length))
     # but I think its harder to read that way, and it compiles using ternary operators anyway
     # so its no slower written like this.
@@ -122,6 +127,10 @@ transformPosition = (pos, c, insertAfter) ->
       c.p
     else
       pos - c.d.length
+  else if c.c?
+    pos
+  else
+    throw new Error("unknown op type")
 
 # Helper method to transform a cursor position as a result of an op.
 #
@@ -143,7 +152,7 @@ text._tc = transformComponent = (dest, c, otherC, side) ->
   if c.i?
     append dest, {i:c.i, p:transformPosition(c.p, otherC, side == 'right')}
 
-  else # Delete
+  else if c.d? # Delete
     if otherC.i? # delete vs insert
       s = c.d
       if c.p < otherC.p
@@ -152,7 +161,7 @@ text._tc = transformComponent = (dest, c, otherC, side) ->
       if s != ''
         append dest, {d:s, p:c.p + otherC.i.length}
 
-    else # Delete vs delete
+    else if otherC.d? # Delete vs delete
       if c.p >= otherC.p + otherC.d.length
         append dest, {d:c.d, p:c.p - otherC.d.length}
       else if c.p + c.d.length <= otherC.p
@@ -177,6 +186,51 @@ text._tc = transformComponent = (dest, c, otherC, side) ->
           # This could be rewritten similarly to insert v delete, above.
           newC.p = transformPosition newC.p, otherC
           append dest, newC
+    
+    else if otherC.c?
+      append dest, c
+    
+    else
+      throw new Error("unknown op type")
+
+  else if c.c? # Comment
+    if otherC.i?
+      if c.p < otherC.p < c.p + c.c.length
+        offset = otherC.p - c.p
+        new_c = (c.c[0..(offset-1)] + otherC.i + c.c[offset...])
+        append dest, {c:new_c, p:c.p}
+      else
+        append dest, {c:c.c, p:transformPosition(c.p, otherC, true)}
+    
+    else if otherC.d?
+      if c.p >= otherC.p + otherC.d.length
+        append dest, {c:c.c, p:c.p - otherC.d.length}
+      else if c.p + c.c.length <= otherC.p
+        append dest, c
+      else # Delete overlaps comment
+        # They overlap somewhere.
+        newC = {c:'', p:c.p}
+        if c.p < otherC.p
+          newC.c = c.c[...(otherC.p - c.p)]
+        if c.p + c.c.length > otherC.p + otherC.d.length
+          newC.c += c.c[(otherC.p + otherC.d.length - c.p)..]
+
+        # This is entirely optional - just for a check that the deleted
+        # text in the two ops matches
+        intersectStart = Math.max c.p, otherC.p
+        intersectEnd = Math.min c.p + c.c.length, otherC.p + otherC.d.length
+        cIntersect = c.c[intersectStart - c.p...intersectEnd - c.p]
+        otherIntersect = otherC.d[intersectStart - otherC.p...intersectEnd - otherC.p]
+        throw new Error 'Delete ops delete different text in the same region of the document' unless cIntersect == otherIntersect
+
+        newC.p = transformPosition newC.p, otherC
+        append dest, newC
+    
+    else if otherC.c?
+      append dest, c
+    
+    else
+      throw new Error("unknown op type")
   
   dest
 

services/document-updater/test/unit/coffee/ShareJS/TextTransformTests.coffee

@@ -0,0 +1,284 @@
+text = require "../../../../app/js/sharejs/types/text"
+require("chai").should()
+RangesTracker = require "../../../../app/js/RangesTracker"
+
+describe "ShareJS text type", ->
+	describe "transform", ->
+		describe "insert / insert", ->
+			it "with an insert before", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 9 }, { i: "bar", p: 3 })
+				dest.should.deep.equal [{ i: "foo", p: 12 }]
+
+			it "with an insert after", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 9 })
+				dest.should.deep.equal [{ i: "foo", p: 3 }]
+
+			it "with an insert at the same place with side == 'right'", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 3 }, 'right')
+				dest.should.deep.equal [{ i: "foo", p: 6 }]
+
+			it "with an insert at the same place with side == 'left'", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 3 }, { i: "bar", p: 3 }, 'left')
+				dest.should.deep.equal [{ i: "foo", p: 3 }]
+
+		describe "insert / delete", ->
+			it "with a delete before", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 9 }, { d: "bar", p: 3 })
+				dest.should.deep.equal [{ i: "foo", p: 6 }]
+
+			it "with a delete after", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 9 })
+				dest.should.deep.equal [{ i: "foo", p: 3 }]
+
+			it "with a delete at the same place with side == 'right'", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 3 }, 'right')
+				dest.should.deep.equal [{ i: "foo", p: 3 }]
+
+			it "with a delete at the same place with side == 'left'", ->
+				dest = []
+				
+				text._tc(dest, { i: "foo", p: 3 }, { d: "bar", p: 3 }, 'left')
+				dest.should.deep.equal [{ i: "foo", p: 3 }]
+
+		describe "delete / insert", ->
+			it "with an insert before", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 9 }, { i: "bar", p: 3 })
+				dest.should.deep.equal [{ d: "foo", p: 12 }]
+
+			it "with an insert after", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 9 })
+				dest.should.deep.equal [{ d: "foo", p: 3 }]
+
+			it "with an insert at the same place with side == 'right'", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 3 }, 'right')
+				dest.should.deep.equal [{ d: "foo", p: 6 }]
+
+			it "with an insert at the same place with side == 'left'", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 3 }, 'left')
+				dest.should.deep.equal [{ d: "foo", p: 6 }]
+			
+			it "with a delete that overlaps the insert location", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { i: "bar", p: 4 })
+				dest.should.deep.equal [{ d: "f", p: 3 }, { d: "oo", p: 6 }]
+				
+
+		describe "delete / delete", ->
+			it "with a delete before", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 9 }, { d: "bar", p: 3 })
+				dest.should.deep.equal [{ d: "foo", p: 6 }]
+
+			it "with a delete after", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { d: "bar", p: 9 })
+				dest.should.deep.equal [{ d: "foo", p: 3 }]
+
+			it "with deleting the same content", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 3 }, { d: "foo", p: 3 }, 'right')
+				dest.should.deep.equal []
+
+			it "with the delete overlapping before", ->
+				dest = []
+				text._tc(dest, { d: "foobar", p: 3 }, { d: "abcfoo", p: 0 }, 'right')
+				dest.should.deep.equal [{ d: "bar", p: 0 }]
+
+			it "with the delete overlapping after", ->
+				dest = []
+				text._tc(dest, { d: "abcfoo", p: 3 }, { d: "foobar", p: 6 })
+				dest.should.deep.equal [{ d: "abc", p: 3 }]
+
+			it "with the delete overlapping the whole delete", ->
+				dest = []
+				text._tc(dest, { d: "abcfoo123", p: 3 }, { d: "foo", p: 6 })
+				dest.should.deep.equal [{ d: "abc123", p: 3 }]
+
+			it "with the delete inside the whole delete", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 6 }, { d: "abcfoo123", p: 3 })
+				dest.should.deep.equal []
+	
+		describe "comment / insert", ->
+			it "with an insert before", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 9 }, { i: "bar", p: 3 })
+				dest.should.deep.equal [{ c: "foo", p: 12 }]
+
+			it "with an insert after", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 3 }, { i: "bar", p: 9 })
+				dest.should.deep.equal [{ c: "foo", p: 3 }]
+
+			it "with an insert at the left edge", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 3 }, { i: "bar", p: 3 })
+				# RangesTracker doesn't inject inserts into comments on edges, so neither should we
+				dest.should.deep.equal [{ c: "foo", p: 6 }]
+
+			it "with an insert at the right edge", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 3 }, { i: "bar", p: 6 })
+				# RangesTracker doesn't inject inserts into comments on edges, so neither should we
+				dest.should.deep.equal [{ c: "foo", p: 3 }]
+
+			it "with an insert in the middle", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 3 }, { i: "bar", p: 5 })
+				dest.should.deep.equal [{ c: "fobaro", p: 3 }]
+	
+		describe "comment / delete", ->
+			it "with a delete before", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 9 }, { d: "bar", p: 3 })
+				dest.should.deep.equal [{ c: "foo", p: 6 }]
+
+			it "with a delete after", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 3 }, { i: "bar", p: 9 })
+				dest.should.deep.equal [{ c: "foo", p: 3 }]
+
+			it "with a delete overlapping the comment content before", ->
+				dest = []
+				text._tc(dest, { c: "foobar", p: 6 }, { d: "123foo", p: 3 })
+				dest.should.deep.equal [{ c: "bar", p: 3 }]
+
+			it "with a delete overlapping the comment content after", ->
+				dest = []
+				text._tc(dest, { c: "foobar", p: 6 }, { d: "bar123", p: 9 })
+				dest.should.deep.equal [{ c: "foo", p: 6 }]
+
+			it "with a delete overlapping the comment content in the middle", ->
+				dest = []
+				text._tc(dest, { c: "foo123bar", p: 6 }, { d: "123", p: 9 })
+				dest.should.deep.equal [{ c: "foobar", p: 6 }]
+
+			it "with a delete overlapping the whole comment", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 6 }, { d: "123foo456", p: 3 })
+				dest.should.deep.equal [{ c: "", p: 3 }]
+	
+		describe "comment / insert", ->
+			it "should not do anything", ->
+				dest = []
+				text._tc(dest, { i: "foo", p: 6 }, { c: "bar", p: 3 })
+				dest.should.deep.equal [{ i: "foo", p: 6 }]
+	
+		describe "comment / delete", ->
+			it "should not do anything", ->
+				dest = []
+				text._tc(dest, { d: "foo", p: 6 }, { c: "bar", p: 3 })
+				dest.should.deep.equal [{ d: "foo", p: 6 }]
+	
+		describe "comment / comment", ->
+			it "should not do anything", ->
+				dest = []
+				text._tc(dest, { c: "foo", p: 6 }, { c: "bar", p: 3 })
+				dest.should.deep.equal [{ c: "foo", p: 6 }]
+
+	describe "apply", ->
+		it "should apply an insert", ->
+			text.apply("foo", [{ i: "bar", p: 2 }]).should.equal "fobaro"
+
+		it "should apply a delete", ->
+			text.apply("foo123bar", [{ d: "123", p: 3 }]).should.equal "foobar"
+
+		it "should do nothing with a comment", ->
+			text.apply("foo123bar", [{ c: "123", p: 3 }]).should.equal "foo123bar"
+		
+		it "should throw an error when deleted content does not match", ->
+			(() ->
+				text.apply("foo123bar", [{ d: "456", p: 3 }])
+			).should.throw(Error)
+		
+		it "should throw an error when comment content does not match", ->
+			(() ->
+				text.apply("foo123bar", [{ c: "456", p: 3 }])
+			).should.throw(Error)
+	
+	describe "applying ops and comments in different orders", ->
+		it "should not matter which op or comment is applied first", ->
+			transform = (op1, op2, side) ->
+				d = []
+				text._tc(d, op1, op2, side)
+				return d
+			
+			applySnapshot = (snapshot, op) ->
+				return text.apply(snapshot, op)
+			
+			applyRanges = (rangesTracker, ops) ->
+				for op in ops
+					if op.c?
+						rangesTracker.addComment(op.p, op.c.length, {})
+					else
+						rangesTracker.applyOp(op, {})
+				return rangesTracker
+			
+			commentsEqual = (comments1, comments2) ->
+				return false if comments1.length != comments2.length
+				comments1.sort (a,b) ->
+					if a.offset - b.offset == 0
+						return a.length - b.length
+					else
+						return a.offset - b.offset
+				comments2.sort (a,b) ->
+					if a.offset - b.offset == 0
+						return a.length - b.length
+					else
+						return a.offset - b.offset
+				for comment1, i in comments1
+					comment2 = comments2[i]
+					if comment1.offset != comment2.offset or comment1.length != comment2.length
+						return false
+				return true
+			
+			SNAPSHOT = "123"
+			
+			OPS = []
+			# Insert ops
+			for p in [0..SNAPSHOT.length]
+				OPS.push {i: "a", p: p}
+				OPS.push {i: "bc", p: p}
+			for p in [0..(SNAPSHOT.length-1)]
+				for length in [1..(SNAPSHOT.length - p)]
+					OPS.push {d: SNAPSHOT.slice(p, p+length), p}
+			for p in [0..(SNAPSHOT.length-1)]
+				for length in [1..(SNAPSHOT.length - p)]
+					OPS.push {c: SNAPSHOT.slice(p, p+length), p}
+			
+			for op1 in OPS
+				for op2 in OPS
+					op1_t = transform(op1, op2, "left")
+					op2_t = transform(op2, op1, "right")
+					
+					rt12 = new RangesTracker()
+					snapshot12 = applySnapshot(applySnapshot(SNAPSHOT, [op1]), op2_t)
+					applyRanges(rt12, [op1])
+					applyRanges(rt12, op2_t)
+					
+					rt21 = new RangesTracker()
+					snapshot21 = applySnapshot(applySnapshot(SNAPSHOT, [op2]), op1_t)
+					applyRanges(rt21, [op2])
+					applyRanges(rt21, op1_t)
+					
+					if snapshot12 != snapshot21
+						console.error {op1, op2, op1_t, op2_t, snapshot12, snapshot21}, "Ops are not consistent"
+						throw new Error("OT is inconsistent")
+					
+					if !commentsEqual(rt12.comments, rt21.comments)
+						console.log rt12.comments
+						console.log rt21.comments
+						console.error {op1, op2, op1_t, op2_t, rt12_comments: rt12.comments, rt21_comments: rt21.comments}, "Comments are not consistent"
+						throw new Error("OT is inconsistent")
+