Get more replies to a comment via /api/morechildren

Also started using slices of pointers instead of slices of structs. This
is useful especially in the case of adding to the list of replies of a
comment. If the comment is a plain old struct (non-pointer), the change
wouldn't happen

Signed-off-by: Vartan Benohanian <vartanbeno@gmail.com>

comment_test.go

@@ -36,8 +36,6 @@ var expectedCommentSubmitOrEdit = &Comment{
 	Edited: &Timestamp{time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC)},
 
 	PostID: "t3_link1",
-
-	Replies: &Replies{},
 }
 
 func TestCommentService_Submit(t *testing.T) {

listings.go

@@ -15,7 +15,7 @@ import (
 type ListingsService service
 
 // Get returns posts, comments, and subreddits from their IDs.
-func (s *ListingsService) Get(ctx context.Context, ids ...string) ([]Post, []Comment, []Subreddit, *Response, error) {
+func (s *ListingsService) Get(ctx context.Context, ids ...string) ([]*Post, []*Comment, []*Subreddit, *Response, error) {
 	type query struct {
 		IDs []string `url:"id,comma"`
 	}
@@ -45,7 +45,7 @@ func (s *ListingsService) Get(ctx context.Context, ids ...string) ([]Post, []Com
 }
 
 // GetPosts returns posts from their full IDs.
-func (s *ListingsService) GetPosts(ctx context.Context, ids ...string) ([]Post, *Response, error) {
+func (s *ListingsService) GetPosts(ctx context.Context, ids ...string) ([]*Post, *Response, error) {
 	if len(ids) == 0 {
 		return nil, nil, errors.New("must provide at least 1 id")
 	}

moderation_test.go

@@ -11,7 +11,7 @@ import (
 )
 
 var expectedModActionsResult = &ModActions{
-	ModActions: []ModAction{
+	ModActions: []*ModAction{
 		{
 			ID:      "ModAction_b4e7979a-c4ad-11ea-8440-0ea1b7c2b8f9",
 			Action:  "spamcomment",

post.go

@@ -62,7 +62,7 @@ type SubmitLinkOptions struct {
 // Get returns a post with its comments.
 // id is the ID36 of the post, not its full id.
 // Example: instead of t3_abc123, use abc123.
-func (s *PostService) Get(ctx context.Context, id string) (*Post, []Comment, *Response, error) {
+func (s *PostService) Get(ctx context.Context, id string) (*Post, []*Comment, *Response, error) {
 	path := fmt.Sprintf("comments/%s", id)
 	req, err := s.client.NewRequest(http.MethodGet, path, nil)
 	if err != nil {
@@ -433,7 +433,22 @@ func (s *PostService) DisableContestMode(ctx context.Context, id string) (*Respo
 // More retrieves more comments that were left out when initially fetching the post.
 // id is the post's full ID.
 // commentIDs are the ID36s of comments.
-func (s *PostService) More(ctx context.Context, id string, commentIDs ...string) (interface{}, *Response, error) {
+func (s *PostService) More(ctx context.Context, comment *Comment) (*Response, error) {
+	if comment == nil {
+		return nil, errors.New("comment: cannot be nil")
+	}
+
+	if comment.Replies.MoreComments == nil {
+		return nil, nil
+	}
+
+	postID := comment.PostID
+	commentIDs := comment.Replies.MoreComments.Children
+
+	if len(commentIDs) == 0 {
+		return nil, nil
+	}
+
 	type query struct {
 		PostID  string   `url:"link_id"`
 		IDs     []string `url:"children,comma"`
@@ -441,21 +456,48 @@ func (s *PostService) More(ctx context.Context, id string, commentIDs ...string)
 	}
 
 	path := "api/morechildren"
-	path, err := addOptions(path, query{id, commentIDs, "json"})
+	path, err := addOptions(path, query{postID, commentIDs, "json"})
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
 	req, err := s.client.NewRequest(http.MethodGet, path, nil)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
-	root := new(interface{})
+	type rootResponse struct {
+		JSON struct {
+			Data struct {
+				Things Things `json:"things"`
+			} `json:"data"`
+		} `json:"json"`
+	}
+
+	root := new(rootResponse)
 	resp, err := s.client.Do(ctx, req, root)
 	if err != nil {
-		return nil, resp, err
+		return resp, err
 	}
 
-	return root, resp, err
+	comments := root.JSON.Data.Things.Comments
+	for _, c := range comments {
+		addCommentToReplies(comment, c)
+	}
+
+	comment.Replies.MoreComments = nil
+	return resp, nil
+}
+
+// addCommentToReplies traverses the comment tree to find the one
+// that the 2nd comment is replying to. It then adds it to its replies.
+func addCommentToReplies(parent *Comment, comment *Comment) {
+	if parent.FullID == comment.ParentID {
+		parent.Replies.Comments = append(parent.Replies.Comments, comment)
+		return
+	}
+
+	for _, reply := range parent.Replies.Comments {
+		addCommentToReplies(reply, comment)
+	}
 }

subreddit.go

@@ -116,12 +116,12 @@ func (s *SubredditService) GetModerated(ctx context.Context, opts *ListOptions)
 }
 
 // GetSticky1 returns the first stickied post on a subreddit (if it exists).
-func (s *SubredditService) GetSticky1(ctx context.Context, name string) (*Post, []Comment, *Response, error) {
+func (s *SubredditService) GetSticky1(ctx context.Context, name string) (*Post, []*Comment, *Response, error) {
 	return s.getSticky(ctx, name, 1)
 }
 
 // GetSticky2 returns the second stickied post on a subreddit (if it exists).
-func (s *SubredditService) GetSticky2(ctx context.Context, name string) (*Post, []Comment, *Response, error) {
+func (s *SubredditService) GetSticky2(ctx context.Context, name string) (*Post, []*Comment, *Response, error) {
 	return s.getSticky(ctx, name, 2)
 }
 
@@ -240,7 +240,7 @@ func (s *SubredditService) getSubreddits(ctx context.Context, path string, opts
 
 // getSticky returns one of the 2 stickied posts of the subreddit (if they exist).
 // Num should be equal to 1 or 2, depending on which one you want.
-func (s *SubredditService) getSticky(ctx context.Context, subreddit string, num int) (*Post, []Comment, *Response, error) {
+func (s *SubredditService) getSticky(ctx context.Context, subreddit string, num int) (*Post, []*Comment, *Response, error) {
 	type query struct {
 		Num int `url:"num"`
 	}

subreddit_test.go

@@ -30,7 +30,7 @@ var expectedSubreddit = &Subreddit{
 var expectedSubreddits = &Subreddits{
 	After:  "t5_2qh0u",
 	Before: "",
-	Subreddits: []Subreddit{
+	Subreddits: []*Subreddit{
 		{
 			ID:      "2qs0k",
 			FullID:  "t5_2qs0k",

things.go

@@ -120,34 +120,34 @@ type Listing struct {
 
 // Things are objects/entities coming from the Reddit API.
 type Things struct {
-	Comments     []Comment
+	Comments     []*Comment
-	MoreComments []More
+	MoreComments []*More
 
-	Users      []User
+	Users      []*User
-	Posts      []Post
+	Posts      []*Post
-	Subreddits []Subreddit
+	Subreddits []*Subreddit
-	ModActions []ModAction
+	ModActions []*ModAction
 	// todo: add the other kinds of things
 }
 
 func (t *Things) init() {
 	if t.Comments == nil {
-		t.Comments = make([]Comment, 0)
+		t.Comments = make([]*Comment, 0)
 	}
 	if t.MoreComments == nil {
-		t.MoreComments = make([]More, 0)
+		t.MoreComments = make([]*More, 0)
 	}
 	if t.Users == nil {
-		t.Users = make([]User, 0)
+		t.Users = make([]*User, 0)
 	}
 	if t.Posts == nil {
-		t.Posts = make([]Post, 0)
+		t.Posts = make([]*Post, 0)
 	}
 	if t.Subreddits == nil {
-		t.Subreddits = make([]Subreddit, 0)
+		t.Subreddits = make([]*Subreddit, 0)
 	}
 	if t.ModActions == nil {
-		t.ModActions = make([]ModAction, 0)
+		t.ModActions = make([]*ModAction, 0)
 	}
 }
 
@@ -166,35 +166,35 @@ func (t *Things) UnmarshalJSON(b []byte) error {
 
 		switch child["kind"] {
 		case kindComment:
-			var v Comment
+			v := new(Comment)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.Comments = append(t.Comments, v)
 			}
 		case kindMore:
-			var v More
+			v := new(More)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.MoreComments = append(t.MoreComments, v)
 			}
 		case kindAccount:
-			var v User
+			v := new(User)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.Users = append(t.Users, v)
 			}
 		case kindLink:
-			var v Post
+			v := new(Post)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.Posts = append(t.Posts, v)
 			}
 		case kindMessage:
 		case kindSubreddit:
-			var v Subreddit
+			v := new(Subreddit)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.Subreddits = append(t.Subreddits, v)
 			}
 		case kindAward:
 		case kindModAction:
-			var v ModAction
+			v := new(ModAction)
-			if err := json.Unmarshal(byteValue, &v); err == nil {
+			if err := json.Unmarshal(byteValue, v); err == nil {
 				t.ModActions = append(t.ModActions, v)
 			}
 		}
@@ -238,7 +238,8 @@ type Comment struct {
 	PostPermalink string `json:"link_permalink,omitempty"`
 	// This doesn't appear when submitting a comment.
 	PostAuthor string `json:"link_author,omitempty"`
-	// This doesn't appear when submitting a comment.
+	// This doesn't appear when submitting a comment
+	// or when getting a post with its comments.
 	PostNumComments int `json:"num_comments"`
 
 	IsSubmitter bool `json:"is_submitter"`
@@ -249,15 +250,15 @@ type Comment struct {
 	CanGild     bool `json:"can_gild"`
 	NSFW        bool `json:"over_18"`
 
-	Replies *Replies `json:"replies"`
+	Replies Replies `json:"replies"`
 }
 
 // Replies holds replies to a comment.
 // It contains both comments and "more" comments, which are entrypoints to other
 // comments that were left out.
 type Replies struct {
-	Comments     []Comment `json:"comments,omitempty"`
+	Comments     []*Comment `json:"comments,omitempty"`
-	MoreComments []More    `json:"more,omitempty"`
+	MoreComments *More      `json:"more,omitempty"`
 }
 
 // UnmarshalJSON implements the json.Unmarshaler interface.
@@ -276,7 +277,9 @@ func (r *Replies) UnmarshalJSON(data []byte) error {
 
 	if root.Data != nil {
 		r.Comments = root.Data.Things.Comments
-		r.MoreComments = root.Data.Things.MoreComments
+		if len(root.Data.Things.MoreComments) > 0 {
+			r.MoreComments = root.Data.Things.MoreComments[0]
+		}
 	}
 
 	return nil
@@ -431,43 +434,43 @@ func (rl *rootListing) getModeratorActions() *ModActions {
 
 // Comments is a list of comments
 type Comments struct {
-	Comments []Comment `json:"comments"`
+	Comments []*Comment `json:"comments"`
-	After    string    `json:"after"`
+	After    string     `json:"after"`
-	Before   string    `json:"before"`
+	Before   string     `json:"before"`
 }
 
 // Users is a list of users
 type Users struct {
-	Users  []User `json:"users"`
+	Users  []*User `json:"users"`
-	After  string `json:"after"`
+	After  string  `json:"after"`
-	Before string `json:"before"`
+	Before string  `json:"before"`
 }
 
 // Subreddits is a list of subreddits
 type Subreddits struct {
-	Subreddits []Subreddit `json:"subreddits"`
+	Subreddits []*Subreddit `json:"subreddits"`
-	After      string      `json:"after"`
+	After      string       `json:"after"`
-	Before     string      `json:"before"`
+	Before     string       `json:"before"`
 }
 
 // Posts is a list of posts.
 type Posts struct {
-	Posts  []Post `json:"posts"`
+	Posts  []*Post `json:"posts"`
-	After  string `json:"after"`
+	After  string  `json:"after"`
-	Before string `json:"before"`
+	Before string  `json:"before"`
 }
 
 // ModActions is a list of moderator action.
 type ModActions struct {
-	ModActions []ModAction `json:"moderator_actions"`
+	ModActions []*ModAction `json:"moderator_actions"`
-	After      string      `json:"after"`
+	After      string       `json:"after"`
-	Before     string      `json:"before"`
+	Before     string       `json:"before"`
 }
 
 // postAndComments is a post and its comments
 type postAndComments struct {
 	Post     *Post
-	Comments []Comment
+	Comments []*Comment
 }
 
 // UnmarshalJSON implements the json.Unmarshaler interface.
@@ -489,7 +492,7 @@ func (pc *postAndComments) UnmarshalJSON(data []byte) error {
 	post := l[0].getPosts().Posts[0]
 	comments := l[1].getComments().Comments
 
-	pc.Post = &post
+	pc.Post = post
 	pc.Comments = comments
 
 	return nil

user_test.go

@@ -46,7 +46,7 @@ var expectedUsers = map[string]*UserShort{
 	},
 }
 
-var expectedPost = Post{
+var expectedPost = &Post{
 	ID:      "gczwql",
 	FullID:  "t3_gczwql",
 	Created: &Timestamp{time.Date(2020, 5, 3, 22, 46, 25, 0, time.UTC)},
@@ -74,7 +74,7 @@ var expectedPost = Post{
 	IsSelfPost: true,
 }
 
-var expectedComment = Comment{
+var expectedComment = &Comment{
 	ID:      "f0zsa37",
 	FullID:  "t1_f0zsa37",
 	Created: &Timestamp{time.Date(2019, 9, 21, 21, 38, 16, 0, time.UTC)},
@@ -101,8 +101,6 @@ var expectedComment = Comment{
 	PostPermalink:   "https://www.reddit.com/r/apple/comments/d7ejpn/im_giving_away_an_iphone_11_pro_to_a_commenter_at/",
 	PostAuthor:      "iamthatis",
 	PostNumComments: 89751,
-
-	Replies: &Replies{},
 }
 
 var expectedRelationship = &Relationship{