1 files changed, 287 insertions, 346 deletions

diff --git a/bridge/github/iterator.go b/bridge/github/iterator.go
index 40b00292..d21faae8 100644
--- a/bridge/github/iterator.go
+++ b/bridge/github/iterator.go
@@ -4,398 +4,371 @@ import (
 	"context"
 	"time"
 
+	"github.com/pkg/errors"
 	"github.com/shurcooL/githubv4"
 )
 
-type indexer struct{ index int }
+type iterator struct {
+	// Github graphql client
+	gc *githubv4.Client
 
-type issueEditIterator struct {
-	index     int
-	query     issueEditQuery
-	variables map[string]interface{}
-}
+	// The iterator will only query issues updated or created after the date given in
+	// the variable since.
+	since time.Time
 
-type commentEditIterator struct {
-	index     int
-	query     commentEditQuery
-	variables map[string]interface{}
-}
+	// Shared context, which is used for all graphql queries.
+	ctx context.Context
 
-type timelineIterator struct {
-	index     int
-	query     issueTimelineQuery
-	variables map[string]interface{}
+	// Sticky error
+	err error
 
-	issueEdit   indexer
-	commentEdit indexer
+	// Issue iterator
+	issueIter issueIter
+}
 
-	// lastEndCursor cache the timeline end cursor for one iteration
-	lastEndCursor githubv4.String
+type issueIter struct {
+	iterVars
+	query         issueQuery
+	issueEditIter []issueEditIter
+	timelineIter  []timelineIter
 }
 
-type iterator struct {
-	// github graphql client
-	gc *githubv4.Client
+type issueEditIter struct {
+	iterVars
+	query issueEditQuery
+}
 
-	// if since is given the iterator will query only the updated
-	// and created issues after this date
-	since time.Time
+type timelineIter struct {
+	iterVars
+	query           timelineQuery
+	commentEditIter []commentEditIter
+}
 
-	// number of timelines/userEditcontent/issueEdit to query
-	// at a time, more capacity = more used memory = less queries
-	// to make
-	capacity int
+type commentEditIter struct {
+	iterVars
+	query commentEditQuery
+}
 
-	// shared context used for all graphql queries
-	ctx context.Context
+type iterVars struct {
+	// Iterator index
+	index int
 
-	// sticky error
-	err error
+	// capacity is the number of elements (issues, issue edits, timeline items, or
+	// comment edits) to query at a time. More capacity = more used memory =
+	// less queries to make.
+	capacity int
 
-	// timeline iterator
-	timeline timelineIterator
+	// Variable assignments for graphql query
+	variables varmap
+}
 
-	// issue edit iterator
-	issueEdit issueEditIterator
+type varmap map[string]interface{}
 
-	// comment edit iterator
-	commentEdit commentEditIterator
+func newIterVars(capacity int) iterVars {
+	return iterVars{
+		index:     -1,
+		capacity:  capacity,
+		variables: varmap{},
+	}
 }
 
-// NewIterator create and initialize a new iterator
+// NewIterator creates and initialize a new iterator.
 func NewIterator(ctx context.Context, client *githubv4.Client, capacity int, owner, project string, since time.Time) *iterator {
 	i := &iterator{
-		gc:       client,
-		since:    since,
-		capacity: capacity,
-		ctx:      ctx,
-		timeline: timelineIterator{
-			index:       -1,
-			issueEdit:   indexer{-1},
-			commentEdit: indexer{-1},
-			variables: map[string]interface{}{
-				"owner": githubv4.String(owner),
-				"name":  githubv4.String(project),
-			},
-		},
-		commentEdit: commentEditIterator{
-			index: -1,
-			variables: map[string]interface{}{
-				"owner": githubv4.String(owner),
-				"name":  githubv4.String(project),
-			},
-		},
-		issueEdit: issueEditIterator{
-			index: -1,
-			variables: map[string]interface{}{
-				"owner": githubv4.String(owner),
-				"name":  githubv4.String(project),
-			},
+		gc:    client,
+		since: since,
+		ctx:   ctx,
+		issueIter: issueIter{
+			iterVars:      newIterVars(capacity),
+			timelineIter:  make([]timelineIter, capacity),
+			issueEditIter: make([]issueEditIter, capacity),
 		},
 	}
-
-	i.initTimelineQueryVariables()
-	return i
-}
-
-// init issue timeline variables
-func (i *iterator) initTimelineQueryVariables() {
-	i.timeline.variables["issueFirst"] = githubv4.Int(1)
-	i.timeline.variables["issueAfter"] = (*githubv4.String)(nil)
-	i.timeline.variables["issueSince"] = githubv4.DateTime{Time: i.since}
-	i.timeline.variables["timelineFirst"] = githubv4.Int(i.capacity)
-	i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
-	// Fun fact, github provide the comment edition in reverse chronological
-	// order, because haha. Look at me, I'm dying of laughter.
-	i.timeline.variables["issueEditLast"] = githubv4.Int(i.capacity)
-	i.timeline.variables["issueEditBefore"] = (*githubv4.String)(nil)
-	i.timeline.variables["commentEditLast"] = githubv4.Int(i.capacity)
-	i.timeline.variables["commentEditBefore"] = (*githubv4.String)(nil)
-}
-
-// init issue edit variables
-func (i *iterator) initIssueEditQueryVariables() {
-	i.issueEdit.variables["issueFirst"] = githubv4.Int(1)
-	i.issueEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
-	i.issueEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
-	i.issueEdit.variables["issueEditLast"] = githubv4.Int(i.capacity)
-	i.issueEdit.variables["issueEditBefore"] = (*githubv4.String)(nil)
-}
-
-// init issue comment variables
-func (i *iterator) initCommentEditQueryVariables() {
-	i.commentEdit.variables["issueFirst"] = githubv4.Int(1)
-	i.commentEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
-	i.commentEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
-	i.commentEdit.variables["timelineFirst"] = githubv4.Int(1)
-	i.commentEdit.variables["timelineAfter"] = (*githubv4.String)(nil)
-	i.commentEdit.variables["commentEditLast"] = githubv4.Int(i.capacity)
-	i.commentEdit.variables["commentEditBefore"] = (*githubv4.String)(nil)
-}
-
-// reverse UserContentEdits arrays in both of the issue and
-// comment timelines
-func (i *iterator) reverseTimelineEditNodes() {
-	node := i.timeline.query.Repository.Issues.Nodes[0]
-	reverseEdits(node.UserContentEdits.Nodes)
-	for index, ce := range node.TimelineItems.Edges {
-		if ce.Node.Typename == "IssueComment" && len(node.TimelineItems.Edges) != 0 {
-			reverseEdits(node.TimelineItems.Edges[index].Node.IssueComment.UserContentEdits.Nodes)
+	i.issueIter.variables.setOwnerProject(owner, project)
+	for idx := range i.issueIter.issueEditIter {
+		ie := &i.issueIter.issueEditIter[idx]
+		ie.iterVars = newIterVars(capacity)
+	}
+	for i1 := range i.issueIter.timelineIter {
+		tli := &i.issueIter.timelineIter[i1]
+		tli.iterVars = newIterVars(capacity)
+		tli.commentEditIter = make([]commentEditIter, capacity)
+		for i2 := range tli.commentEditIter {
+			cei := &tli.commentEditIter[i2]
+			cei.iterVars = newIterVars(capacity)
 		}
 	}
+	i.resetIssueVars()
+	return i
 }
 
-// Error return last encountered error
-func (i *iterator) Error() error {
-	return i.err
+func (v *varmap) setOwnerProject(owner, project string) {
+	(*v)["owner"] = githubv4.String(owner)
+	(*v)["name"] = githubv4.String(project)
 }
 
-func (i *iterator) queryIssue() bool {
-	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
-	defer cancel()
-
-	if err := i.gc.Query(ctx, &i.timeline.query, i.timeline.variables); err != nil {
-		i.err = err
-		return false
-	}
+func (i *iterator) resetIssueVars() {
+	vars := &i.issueIter.variables
+	(*vars)["issueFirst"] = githubv4.Int(i.issueIter.capacity)
+	(*vars)["issueAfter"] = (*githubv4.String)(nil)
+	(*vars)["issueSince"] = githubv4.DateTime{Time: i.since}
+	i.issueIter.query.Repository.Issues.PageInfo.HasNextPage = true
+	i.issueIter.query.Repository.Issues.PageInfo.EndCursor = ""
+}
 
-	issues := i.timeline.query.Repository.Issues.Nodes
-	if len(issues) == 0 {
-		return false
+func (i *iterator) resetIssueEditVars() {
+	for idx := range i.issueIter.issueEditIter {
+		ie := &i.issueIter.issueEditIter[idx]
+		ie.variables["issueEditLast"] = githubv4.Int(ie.capacity)
+		ie.variables["issueEditBefore"] = (*githubv4.String)(nil)
+		ie.query.Node.Issue.UserContentEdits.PageInfo.HasNextPage = true
+		ie.query.Node.Issue.UserContentEdits.PageInfo.EndCursor = ""
 	}
-
-	i.reverseTimelineEditNodes()
-	return true
 }
 
-// NextIssue try to query the next issue and return true. Only one issue is
-// queried at each call.
-func (i *iterator) NextIssue() bool {
-	if i.err != nil {
-		return false
+func (i *iterator) resetTimelineVars() {
+	for idx := range i.issueIter.timelineIter {
+		ip := &i.issueIter.timelineIter[idx]
+		ip.variables["timelineFirst"] = githubv4.Int(ip.capacity)
+		ip.variables["timelineAfter"] = (*githubv4.String)(nil)
+		ip.query.Node.Issue.TimelineItems.PageInfo.HasNextPage = true
+		ip.query.Node.Issue.TimelineItems.PageInfo.EndCursor = ""
 	}
+}
 
-	// if $issueAfter variable is nil we can directly make the first query
-	if i.timeline.variables["issueAfter"] == (*githubv4.String)(nil) {
-		nextIssue := i.queryIssue()
-		// prevent from infinite loop by setting a non nil cursor
-		issues := i.timeline.query.Repository.Issues
-		i.timeline.variables["issueAfter"] = issues.PageInfo.EndCursor
-		return nextIssue
+func (i *iterator) resetCommentEditVars() {
+	for i1 := range i.issueIter.timelineIter {
+		for i2 := range i.issueIter.timelineIter[i1].commentEditIter {
+			ce := &i.issueIter.timelineIter[i1].commentEditIter[i2]
+			ce.variables["commentEditLast"] = githubv4.Int(ce.capacity)
+			ce.variables["commentEditBefore"] = (*githubv4.String)(nil)
+			ce.query.Node.IssueComment.UserContentEdits.PageInfo.HasNextPage = true
+			ce.query.Node.IssueComment.UserContentEdits.PageInfo.EndCursor = ""
+		}
 	}
+}
 
-	issues := i.timeline.query.Repository.Issues
-	if !issues.PageInfo.HasNextPage {
-		return false
+// Error return last encountered error
+func (i *iterator) Error() error {
+	if i.err != nil {
+		return i.err
 	}
+	return i.ctx.Err() // might return nil
+}
 
-	// if we have more issues, query them
-	i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
-	i.timeline.index = -1
-
-	timelineEndCursor := issues.Nodes[0].TimelineItems.PageInfo.EndCursor
-	// store cursor for future use
-	i.timeline.lastEndCursor = timelineEndCursor
+func (i *iterator) HasError() bool {
+	return i.err != nil || i.ctx.Err() != nil
+}
 
-	// query issue block
-	nextIssue := i.queryIssue()
-	i.timeline.variables["issueAfter"] = issues.PageInfo.EndCursor
+func (i *iterator) currIssueItem() *issue {
+	return &i.issueIter.query.Repository.Issues.Nodes[i.issueIter.index]
+}
 
-	return nextIssue
+func (i *iterator) currIssueEditIter() *issueEditIter {
+	return &i.issueIter.issueEditIter[i.issueIter.index]
 }
 
-// IssueValue return the actual issue value
-func (i *iterator) IssueValue() issueTimeline {
-	issues := i.timeline.query.Repository.Issues
-	return issues.Nodes[0]
+func (i *iterator) currTimelineIter() *timelineIter {
+	return &i.issueIter.timelineIter[i.issueIter.index]
 }
 
-// NextTimelineItem return true if there is a next timeline item and increments the index by one.
-// It is used iterates over all the timeline items. Extra queries are made if it is necessary.
-func (i *iterator) NextTimelineItem() bool {
-	if i.err != nil {
-		return false
-	}
+func (i *iterator) currCommentEditIter() *commentEditIter {
+	timelineIter := i.currTimelineIter()
+	return &timelineIter.commentEditIter[timelineIter.index]
+}
 
-	if i.ctx.Err() != nil {
-		return false
-	}
+func (i *iterator) currIssueGqlNodeId() githubv4.ID {
+	return i.currIssueItem().Id
+}
 
-	timelineItems := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
-	// after NextIssue call it's good to check wether we have some timelineItems items or not
-	if len(timelineItems.Edges) == 0 {
+// NextIssue returns true if there exists a next issue and advances the iterator by one.
+// It is used to iterate over all issues. Queries to github are made when necessary.
+func (i *iterator) NextIssue() bool {
+	if i.HasError() {
 		return false
 	}
-
-	if i.timeline.index < len(timelineItems.Edges)-1 {
-		i.timeline.index++
+	index := &i.issueIter.index
+	issues := &i.issueIter.query.Repository.Issues
+	issueItems := &issues.Nodes
+	if 0 <= *index && *index < len(*issueItems)-1 {
+		*index += 1
 		return true
 	}
 
-	if !timelineItems.PageInfo.HasNextPage {
+	if !issues.PageInfo.HasNextPage {
 		return false
 	}
+	nextIssue := i.queryIssue()
+	return nextIssue
+}
 
-	i.timeline.lastEndCursor = timelineItems.PageInfo.EndCursor
-
-	// more timelines, query them
-	i.timeline.variables["timelineAfter"] = timelineItems.PageInfo.EndCursor
+// IssueValue returns the actual issue value.
+func (i *iterator) IssueValue() issue {
+	return *i.currIssueItem()
+}
 
+func (i *iterator) queryIssue() bool {
 	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
 	defer cancel()
-
-	if err := i.gc.Query(ctx, &i.timeline.query, i.timeline.variables); err != nil {
+	if endCursor := i.issueIter.query.Repository.Issues.PageInfo.EndCursor; endCursor != "" {
+		i.issueIter.variables["issueAfter"] = endCursor
+	}
+	if err := i.gc.Query(ctx, &i.issueIter.query, i.issueIter.variables); err != nil {
 		i.err = err
 		return false
 	}
-
-	timelineItems = i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
-	// (in case github returns something weird) just for safety: better return a false than a panic
-	if len(timelineItems.Edges) == 0 {
+	i.resetIssueEditVars()
+	i.resetTimelineVars()
+	issueItems := &i.issueIter.query.Repository.Issues.Nodes
+	if len(*issueItems) <= 0 {
+		i.issueIter.index = -1
 		return false
 	}
-
-	i.reverseTimelineEditNodes()
-	i.timeline.index = 0
+	i.issueIter.index = 0
 	return true
 }
 
-// TimelineItemValue return the actual timeline item value
-func (i *iterator) TimelineItemValue() timelineItem {
-	timelineItems := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
-	return timelineItems.Edges[i.timeline.index].Node
-}
-
-func (i *iterator) queryIssueEdit() bool {
-	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
-	defer cancel()
-
-	if err := i.gc.Query(ctx, &i.issueEdit.query, i.issueEdit.variables); err != nil {
-		i.err = err
-		//i.timeline.issueEdit.index = -1
+// NextIssueEdit returns true if there exists a next issue edit and advances the iterator
+// by one. It is used to iterate over all the issue edits. Queries to github are made when
+// necessary.
+func (i *iterator) NextIssueEdit() bool {
+	if i.HasError() {
 		return false
 	}
-
-	issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
-	// reverse issue edits because github
-	reverseEdits(issueEdits.Nodes)
-
-	// this is not supposed to happen
-	if len(issueEdits.Nodes) == 0 {
-		i.timeline.issueEdit.index = -1
+	ieIter := i.currIssueEditIter()
+	ieIdx := &ieIter.index
+	ieItems := ieIter.query.Node.Issue.UserContentEdits
+	if 0 <= *ieIdx && *ieIdx < len(ieItems.Nodes)-1 {
+		*ieIdx += 1
+		return i.nextValidIssueEdit()
+	}
+	if !ieItems.PageInfo.HasNextPage {
+		return false
+	}
+	querySucc := i.queryIssueEdit()
+	if !querySucc {
 		return false
 	}
-
-	i.issueEdit.index = 0
-	i.timeline.issueEdit.index = -2
 	return i.nextValidIssueEdit()
 }
 
 func (i *iterator) nextValidIssueEdit() bool {
-	// issueEdit.Diff == nil happen if the event is older than early 2018, Github doesn't have the data before that.
-	// Best we can do is to ignore the event.
+	// issueEdit.Diff == nil happen if the event is older than early 2018, Github doesn't have
+	// the data before that. Best we can do is to ignore the event.
 	if issueEdit := i.IssueEditValue(); issueEdit.Diff == nil || string(*issueEdit.Diff) == "" {
 		return i.NextIssueEdit()
 	}
 	return true
 }
 
-// NextIssueEdit return true if there is a next issue edit and increments the index by one.
-// It is used iterates over all the issue edits. Extra queries are made if it is necessary.
-func (i *iterator) NextIssueEdit() bool {
-	if i.err != nil {
+// IssueEditValue returns the actual issue edit value.
+func (i *iterator) IssueEditValue() userContentEdit {
+	iei := i.currIssueEditIter()
+	return iei.query.Node.Issue.UserContentEdits.Nodes[iei.index]
+}
+
+func (i *iterator) queryIssueEdit() bool {
+	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
+	defer cancel()
+	iei := i.currIssueEditIter()
+	if endCursor := iei.query.Node.Issue.UserContentEdits.PageInfo.EndCursor; endCursor != "" {
+		iei.variables["issueEditBefore"] = endCursor
+	}
+	iei.variables["gqlNodeId"] = i.currIssueGqlNodeId()
+	if err := i.gc.Query(ctx, &iei.query, iei.variables); err != nil {
+		i.err = err
 		return false
 	}
-
-	if i.ctx.Err() != nil {
+	issueEditItems := iei.query.Node.Issue.UserContentEdits.Nodes
+	if len(issueEditItems) <= 0 {
+		iei.index = -1
 		return false
 	}
+	// The UserContentEditConnection in the Github API serves its elements in reverse chronological
+	// order. For our purpose we have to reverse the edits.
+	reverseEdits(issueEditItems)
+	iei.index = 0
+	return true
+}
 
-	// this mean we looped over all available issue edits in the timeline.
-	// now we have to use i.issueEditQuery
-	if i.timeline.issueEdit.index == -2 {
-		issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
-		if i.issueEdit.index < len(issueEdits.Nodes)-1 {
-			i.issueEdit.index++
-			return i.nextValidIssueEdit()
-		}
-
-		if !issueEdits.PageInfo.HasPreviousPage {
-			i.timeline.issueEdit.index = -1
-			i.issueEdit.index = -1
-			return false
-		}
-
-		// if there is more edits, query them
-		i.issueEdit.variables["issueEditBefore"] = issueEdits.PageInfo.StartCursor
-		return i.queryIssueEdit()
-	}
-
-	issueEdits := i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits
-	// if there is no edit, the UserContentEdits given by github is empty. That
-	// means that the original message is given by the issue message.
-	//
-	// if there is edits, the UserContentEdits given by github contains both the
-	// original message and the following edits. The issue message give the last
-	// version so we don't care about that.
-	//
-	// the tricky part: for an issue older than the UserContentEdits API, github
-	// doesn't have the previous message version anymore and give an edition
-	// with .Diff == nil. We have to filter them.
-	if len(issueEdits.Nodes) == 0 {
+// NextTimelineItem returns true if there exists a next timeline item and advances the iterator
+// by one. It is used to iterate over all the timeline items. Queries to github are made when
+// necessary.
+func (i *iterator) NextTimelineItem() bool {
+	if i.HasError() {
 		return false
 	}
-
-	// loop over them timeline comment edits
-	if i.timeline.issueEdit.index < len(issueEdits.Nodes)-1 {
-		i.timeline.issueEdit.index++
-		return i.nextValidIssueEdit()
+	tlIter := &i.issueIter.timelineIter[i.issueIter.index]
+	tlIdx := &tlIter.index
+	tlItems := tlIter.query.Node.Issue.TimelineItems
+	if 0 <= *tlIdx && *tlIdx < len(tlItems.Nodes)-1 {
+		*tlIdx += 1
+		return true
 	}
-
-	if !issueEdits.PageInfo.HasPreviousPage {
-		i.timeline.issueEdit.index = -1
+	if !tlItems.PageInfo.HasNextPage {
 		return false
 	}
-
-	// if there is more edits, query them
-	i.initIssueEditQueryVariables()
-	i.issueEdit.variables["issueEditBefore"] = issueEdits.PageInfo.StartCursor
-	return i.queryIssueEdit()
+	nextTlItem := i.queryTimeline()
+	return nextTlItem
 }
 
-// IssueEditValue return the actual issue edit value
-func (i *iterator) IssueEditValue() userContentEdit {
-	// if we are using issue edit query
-	if i.timeline.issueEdit.index == -2 {
-		issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
-		return issueEdits.Nodes[i.issueEdit.index]
-	}
-
-	issueEdits := i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits
-	// else get it from timeline issue edit query
-	return issueEdits.Nodes[i.timeline.issueEdit.index]
+// TimelineItemValue returns the actual timeline item value.
+func (i *iterator) TimelineItemValue() timelineItem {
+	tli := i.currTimelineIter()
+	return tli.query.Node.Issue.TimelineItems.Nodes[tli.index]
 }
 
-func (i *iterator) queryCommentEdit() bool {
+func (i *iterator) queryTimeline() bool {
 	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
 	defer cancel()
-
-	if err := i.gc.Query(ctx, &i.commentEdit.query, i.commentEdit.variables); err != nil {
+	tli := i.currTimelineIter()
+	if endCursor := tli.query.Node.Issue.TimelineItems.PageInfo.EndCursor; endCursor != "" {
+		tli.variables["timelineAfter"] = endCursor
+	}
+	tli.variables["gqlNodeId"] = i.currIssueGqlNodeId()
+	if err := i.gc.Query(ctx, &tli.query, tli.variables); err != nil {
 		i.err = err
 		return false
 	}
+	i.resetCommentEditVars()
+	timelineItems := &tli.query.Node.Issue.TimelineItems
+	if len(timelineItems.Nodes) <= 0 {
+		tli.index = -1
+		return false
+	}
+	tli.index = 0
+	return true
+}
 
-	commentEdits := i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits
-	// this is not supposed to happen
-	if len(commentEdits.Nodes) == 0 {
-		i.timeline.commentEdit.index = -1
+// NextCommentEdit returns true if there exists a next comment edit and advances the iterator
+// by one. It is used to iterate over all issue edits. Queries to github are made when
+// necessary.
+func (i *iterator) NextCommentEdit() bool {
+	if i.HasError() {
 		return false
 	}
 
-	reverseEdits(commentEdits.Nodes)
+	tmlnVal := i.TimelineItemValue()
+	if tmlnVal.Typename != "IssueComment" {
+		// The timeline iterator does not point to a comment.
+		i.err = errors.New("Call to NextCommentEdit() while timeline item is not a comment")
+		return false
+	}
 
-	i.commentEdit.index = 0
-	i.timeline.commentEdit.index = -2
+	cei := i.currCommentEditIter()
+	ceIdx := &cei.index
+	ceItems := &cei.query.Node.IssueComment.UserContentEdits
+	if 0 <= *ceIdx && *ceIdx < len(ceItems.Nodes)-1 {
+		*ceIdx += 1
+		return i.nextValidCommentEdit()
+	}
+	if !ceItems.PageInfo.HasNextPage {
+		return false
+	}
+	querySucc := i.queryCommentEdit()
+	if !querySucc {
+		return false
+	}
 	return i.nextValidCommentEdit()
 }
 
@@ -407,72 +380,40 @@ func (i *iterator) nextValidCommentEdit() bool {
 	return true
 }
 
-// NextCommentEdit return true if there is a next comment edit and increments the index by one.
-// It is used iterates over all the comment edits. Extra queries are made if it is necessary.
-func (i *iterator) NextCommentEdit() bool {
-	if i.err != nil {
-		return false
-	}
-
-	if i.ctx.Err() != nil {
-		return false
-	}
-
-	// same as NextIssueEdit
-	if i.timeline.commentEdit.index == -2 {
-		commentEdits := i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits
-		if i.commentEdit.index < len(commentEdits.Nodes)-1 {
-			i.commentEdit.index++
-			return i.nextValidCommentEdit()
-		}
+// CommentEditValue returns the actual comment edit value.
+func (i *iterator) CommentEditValue() userContentEdit {
+	cei := i.currCommentEditIter()
+	return cei.query.Node.IssueComment.UserContentEdits.Nodes[cei.index]
+}
 
-		if !commentEdits.PageInfo.HasPreviousPage {
-			i.timeline.commentEdit.index = -1
-			i.commentEdit.index = -1
-			return false
-		}
+func (i *iterator) queryCommentEdit() bool {
+	ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
+	defer cancel()
+	cei := i.currCommentEditIter()
 
-		// if there is more comment edits, query them
-		i.commentEdit.variables["commentEditBefore"] = commentEdits.PageInfo.StartCursor
-		return i.queryCommentEdit()
+	if endCursor := cei.query.Node.IssueComment.UserContentEdits.PageInfo.EndCursor; endCursor != "" {
+		cei.variables["commentEditBefore"] = endCursor
 	}
-
-	commentEdits := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index].Node.IssueComment
-	// if there is no comment edits
-	if len(commentEdits.UserContentEdits.Nodes) == 0 {
+	tmlnVal := i.TimelineItemValue()
+	if tmlnVal.Typename != "IssueComment" {
+		i.err = errors.New("Call to queryCommentEdit() while timeline item is not a comment")
 		return false
 	}
-
-	// loop over them timeline comment edits
-	if i.timeline.commentEdit.index < len(commentEdits.UserContentEdits.Nodes)-1 {
-		i.timeline.commentEdit.index++
-		return i.nextValidCommentEdit()
-	}
-
-	if !commentEdits.UserContentEdits.PageInfo.HasPreviousPage {
-		i.timeline.commentEdit.index = -1
+	cei.variables["gqlNodeId"] = tmlnVal.IssueComment.Id
+	if err := i.gc.Query(ctx, &cei.query, cei.variables); err != nil {
+		i.err = err
 		return false
 	}
-
-	i.initCommentEditQueryVariables()
-	if i.timeline.index == 0 {
-		i.commentEdit.variables["timelineAfter"] = i.timeline.lastEndCursor
-	} else {
-		i.commentEdit.variables["timelineAfter"] = i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index-1].Cursor
-	}
-
-	i.commentEdit.variables["commentEditBefore"] = commentEdits.UserContentEdits.PageInfo.StartCursor
-
-	return i.queryCommentEdit()
-}
-
-// CommentEditValue return the actual comment edit value
-func (i *iterator) CommentEditValue() userContentEdit {
-	if i.timeline.commentEdit.index == -2 {
-		return i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes[i.commentEdit.index]
+	ceItems := cei.query.Node.IssueComment.UserContentEdits.Nodes
+	if len(ceItems) <= 0 {
+		cei.index = -1
+		return false
 	}
-
-	return i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.Nodes[i.timeline.commentEdit.index]
+	// The UserContentEditConnection in the Github API serves its elements in reverse chronological
+	// order. For our purpose we have to reverse the edits.
+	reverseEdits(ceItems)
+	cei.index = 0
+	return true
 }
 
 func reverseEdits(edits []userContentEdit) {