client/posts: fix editing post safety

Broken by 865c4f3b79

API.md

@@ -36,6 +36,7 @@
         - [Updating post](#updating-post)
         - [Getting post](#getting-post)
         - [Deleting post](#deleting-post)
+        - [Merging posts](#merging-posts)
         - [Rating post](#rating-post)
         - [Adding post to favorites](#adding-post-to-favorites)
         - [Removing post from favorites](#removing-post-from-favorites)
@@ -617,10 +618,9 @@ data.
 
 - **Description**
 
-    Removes source tag and merges all of its usages to the target tag. Source
-    tag properties such as category, tag relations etc. do not get transferred
-    and are discarded. The target tag effectively remains unchanged with the
-    exception of the set of posts it's used in.
+    Removes source tag and merges all of its usages, suggestions and
+    implications to the target tag. Other tag properties such as category and
+    aliases do not get transferred and are discarded.
 
 ## Listing tag siblings
 - **Request**
@@ -910,6 +910,43 @@ data.
 
     Deletes existing post. Related posts and tags are kept.
 
+## Merging posts
+- **Request**
+
+    `POST /post-merge/`
+
+- **Input**
+
+    ```json5
+    {
+        "removeVersion":  <source-post-version>,
+        "remove":         <source-post-id>,
+        "mergeToVersion": <target-post-version>,
+        "mergeTo":        <target-post-id>,
+        "replaceContent": <true-or-false>
+    }
+    ```
+
+- **Output**
+
+    A [post resource](#post) containing the merged post.
+
+- **Errors**
+
+    - the version of either post is outdated
+    - the source or target post does not exist
+    - the source post is the same as the target post
+    - privileges are too low
+
+- **Description**
+
+    Removes source post and merges all of its tags, relations, scores,
+    favorites and comments to the target post. If `replaceContent` is set to
+    true, content of the target post is replaced using the content of the
+    source post; otherwise it remains unchanged. Source post properties such as
+    its safety, source, whether to loop the video and other scalar values do
+    not get transferred and are discarded.
+
 ## Rating post
 - **Request**
 

client/css/core-forms.styl

@@ -65,10 +65,9 @@ input[type=radio], input[type=checkbox]
 .radio:before, .checkbox:before
     transition: border-color 0.1s linear
     position: absolute
-    top: 50%
     left: 0
+    top: 0.15em
     display: block
-    margin-top: -10px
     width: 16px
     height: 16px
     background: $input-enabled-background-color
@@ -79,10 +78,10 @@ input[type=radio], input[type=checkbox]
     background: $main-color
     transition: opacity 0.1s linear
     position: absolute
-    top: 50%
     left: 5px
+    top: 0.15em
+    margin-top: 5px
     display: block
-    margin-top: -5px
     width: 10px
     height: 10px
     border-radius: 50%
@@ -92,10 +91,10 @@ input[type=radio], input[type=checkbox]
 .checkbox:after
     transition: opacity 0.1s linear
     position: absolute
-    top: 50%
+    top: 0.15em
     left: 6px
     display: block
-    margin-top: -7px
+    margin-top: 3px
     width: 5px
     height: 9px
     border-right: 3px solid $main-color

client/css/post-detail-view.styl

@@ -0,0 +1,33 @@
+#post
+    width: 100%
+    max-width: 40em
+    h1
+        margin-top: 0
+    form
+        width: 100%
+    .buttons i
+        margin-right: 0.5em
+    .post-merge
+        .left-post-container
+            width: 47%
+            float: left
+        .right-post-container
+            width: 47%
+            float: right
+        input[type=text]
+            width: 8em
+            margin-top: -2px
+        .post-mirror
+            margin-bottom: 1em
+            &:after
+                display: block
+                height: 1px
+                content: ' '
+                clear: both
+        .post-thumbnail .thumbnail
+            width: 100%
+            height: 9em
+        .target-post .thumbnail
+            margin-right: 0.35em
+        .target-post, .target-post-content
+            margin: 1em 0

client/css/post-main-view.styl

@@ -120,11 +120,12 @@
             margin-bottom: 1em
 
     .safety
-        display: flex
-        flex-wrap: wrap
-        label:not(.radio)
+        &>label
             width: 100%
-        .radio
+        .radio-wrapper
+            display: flex
+            flex-wrap: wrap
+        .radio-wrapper label
             flex-grow: 1
             display: inline-block
 

client/css/post-upload.styl

@@ -39,20 +39,24 @@ $cancel-button-color = tomato
         margin-top: 1em
 
     .uploadables-container
-        line-height: 200%
-
         li
             margin: 0 0 1.2em 0
 
         .uploadable
             .file
+                margin: 0.3em 0
                 overflow: hidden
                 white-space: nowrap
                 text-align: left
                 text-overflow: ellipsis
 
+            .anonymous
+                margin: 0.3em 0
+
             .safety
+                margin: 0.3em 0
                 label
+                    display: inline-block
                     margin-right: 1em
 
             .thumbnail-wrapper

client/html/post_detail.tpl

@@ -0,0 +1,12 @@
+<div class='content-wrapper' id='post'>
+    <h1>Post #<%- ctx.post.id %></h1>
+    <nav class='buttons'><!--
+        --><ul><!--
+            --><li><a href='/post/<%- ctx.post.id %>'><i class='fa fa-reply'></i> Main view</a></li><!--
+            --><% if (ctx.canMerge) { %><!--
+                --><li data-name='merge'><a href='/post/<%- ctx.post.id %>/merge'>Merge with&hellip;</a></li><!--
+            --><% } %><!--
+        --></ul><!--
+    --></nav>
+    <div class='post-content-holder'></div>
+</div>

client/html/post_edit_sidebar.tpl

@@ -7,24 +7,26 @@
         <% if (ctx.canEditPostSafety) { %>
             <section class='safety'>
                 <label>Safety</label>
-                <%= ctx.makeRadio({
-                    name: 'safety',
-                    class: 'safety-safe',
-                    value: 'safe',
-                    selectedValue: ctx.post.safety,
-                    text: 'Safe'}) %>
-                <%= ctx.makeRadio({
-                    name: 'safety',
-                    class: 'safety-sketchy',
-                    value: 'sketchy',
-                    selectedValue: ctx.post.safety,
-                    text: 'Sketchy'}) %>
-                <%= ctx.makeRadio({
-                    name: 'safety',
-                    value: 'unsafe',
-                    selectedValue: ctx.post.safety,
-                    class: 'safety-unsafe',
-                    text: 'Unsafe'}) %>
+                <div class='radio-wrapper'>
+                    <%= ctx.makeRadio({
+                        name: 'safety',
+                        class: 'safety-safe',
+                        value: 'safe',
+                        selectedValue: ctx.post.safety,
+                        text: 'Safe'}) %>
+                    <%= ctx.makeRadio({
+                        name: 'safety',
+                        class: 'safety-sketchy',
+                        value: 'sketchy',
+                        selectedValue: ctx.post.safety,
+                        text: 'Sketchy'}) %>
+                    <%= ctx.makeRadio({
+                        name: 'safety',
+                        value: 'unsafe',
+                        selectedValue: ctx.post.safety,
+                        class: 'safety-unsafe',
+                        text: 'Unsafe'}) %>
+                </div>
             </section>
         <% } %>
 
@@ -82,12 +84,15 @@
             </section>
         <% } %>
 
-        <% if (ctx.canFeaturePosts) { %>
+        <% if (ctx.canFeaturePosts || ctx.canDeletePosts || ctx.canMergePosts) { %>
             <section class='management'>
                 <ul>
                     <% if (ctx.canFeaturePosts) { %>
                         <li><a href class='feature'>Feature this post on main page</a></li>
                     <% } %>
+                    <% if (ctx.canMergePosts) { %>
+                        <li><a href class='merge'>Merge this post with another</a></li>
+                    <% } %>
                     <% if (ctx.canDeletePosts) { %>
                         <li><a href class='delete'>Delete this post</a></li>
                     <% } %>

client/html/post_merge.tpl

@@ -0,0 +1,23 @@
+<div class='post-merge'>
+    <form>
+        <ul>
+            <li class='post-mirror'>
+                <div class='left-post-container'></div>
+                <div class='right-post-container'></div>
+            </li>
+
+            <li>
+                <p>Tags, relations, scores, favorites and comments will be
+                merged. All other properties need to be handled manually.</p>
+
+                <%= ctx.makeCheckbox({required: true, text: 'I confirm that I want to merge these posts.'}) %>
+            </li>
+        </ul>
+
+        <div class='messages'></div>
+
+        <div class='buttons'>
+            <input type='submit' value='Merge posts'/>
+        </div>
+    </form>
+</div>

client/html/post_merge_side.tpl

@@ -0,0 +1,48 @@
+<% if (ctx.editable) { %>
+    <p>Post # <input type='text' pattern='^[0-9]+$' value='<%- ctx.post ? ctx.post.id : '' %>'/></p>
+<% } else { %>
+    <p>Post # <input type='text' pattern='^[0-9]+$' value='<%- ctx.post ? ctx.post.id : '' %>' readonly/></p>
+<% } %>
+
+<% if (ctx.post) { %>
+    <div class='post-thumbnail'>
+        <a rel='external' href='<%- ctx.post.contentUrl %>'>
+            <%= ctx.makeThumbnail(ctx.post.thumbnailUrl) %>
+        </a>
+    </div>
+    <div class='target-post'>
+        <%= ctx.makeRadio({
+            required: true,
+            text: 'Merge to this post<br/><small>' +
+                ctx.makeUserLink(ctx.post.user) +
+                ', ' +
+                ctx.makeRelativeTime(ctx.post.creationTime) +
+                '</small>',
+            name: 'target-post',
+            value: ctx.name,
+        }) %>
+    </div>
+    <div class='target-post-content'>
+        <%= ctx.makeRadio({
+            required: true,
+            text: 'Use this file<br/><small>' +
+                ctx.makeFileSize(ctx.post.fileSize) + ' ' +
+                {
+                    'image/gif': 'GIF',
+                    'image/jpeg': 'JPEG',
+                    'image/png': 'PNG',
+                    'video/webm': 'WEBM',
+                    'application/x-shockwave-flash': 'SWF',
+                }[ctx.post.mimeType] +
+                ' (' +
+                (ctx.post.canvasWidth ?
+                    `${ctx.post.canvasWidth}x${ctx.post.canvasHeight}` :
+                    '?') +
+                ')</small>',
+            name: 'target-post-content',
+            value: ctx.name,
+        }) %>
+        <p>
+        </p>
+    </div>
+<% } %>

client/html/tag_merge.tpl

@@ -1,14 +1,14 @@
 <div class='tag-merge'>
     <form>
-        <p>Proceeding will remove this tag and retag its posts with the tag
-        specified below. Aliases, suggestions and implications are discarded
-        and need to be handled manually.</p>
-
         <ul>
             <li class='target'>
                 <%= ctx.makeTextInput({required: true, text: 'Target tag', pattern: ctx.tagNamePattern}) %>
             </li>
-            <li class='confirm'>
+
+            <li>
+                <p>Usages in posts, suggestions and implications will be
+                merged. Category and aliases need to be handled manually.</p>
+
                 <%= ctx.makeCheckbox({required: true, text: 'I confirm that I want to merge this tag.'}) %>
             </li>
         </ul>

client/js/controllers/base_post_controller.js

@@ -0,0 +1,20 @@
+'use strict';
+
+const api = require('../api.js');
+const topNavigation = require('../models/top_navigation.js');
+const EmptyView = require('../views/empty_view.js');
+
+class BasePostController {
+    constructor(ctx) {
+        if (!api.hasPrivilege('posts:view')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view posts.');
+            return;
+        }
+
+        topNavigation.activate('posts');
+        topNavigation.setTitle('Post #' + ctx.parameters.id.toString());
+    }
+}
+
+module.exports = BasePostController;

client/js/controllers/post_detail_controller.js

@@ -0,0 +1,86 @@
+'use strict';
+
+const router = require('../router.js');
+const api = require('../api.js');
+const misc = require('../util/misc.js');
+const settings = require('../models/settings.js');
+const Comment = require('../models/comment.js');
+const Post = require('../models/post.js');
+const PostList = require('../models/post_list.js');
+const PostDetailView = require('../views/post_detail_view.js');
+const BasePostController = require('./base_post_controller.js');
+const EmptyView = require('../views/empty_view.js');
+
+class PostDetailController extends BasePostController {
+    constructor(ctx, section) {
+        super(ctx);
+
+        Post.get(ctx.parameters.id).then(post => {
+            this._id = ctx.parameters.id;
+            post.addEventListener('change', e => this._evtSaved(e, section));
+
+            this._view = new PostDetailView({
+                post: post,
+                section: section,
+                canMerge: api.hasPrivilege('posts:merge'),
+            });
+
+            this._view.addEventListener('select', e => this._evtSelect(e));
+            this._view.addEventListener('merge', e => this._evtMerge(e));
+        }, errorMessage => {
+            this._view = new EmptyView();
+            this._view.showError(errorMessage);
+        });
+    }
+
+    showSuccess(message) {
+        this._view.showSuccess(message);
+    }
+
+    _evtSelect(e) {
+        this._view.clearMessages();
+        this._view.disableForm();
+        Post.get(e.detail.postId).then(post => {
+            this._view.selectPost(post);
+            this._view.enableForm();
+        }, errorMessage => {
+            this._view.showError(errorMessage);
+            this._view.enableForm();
+        });
+    }
+
+    _evtSaved(e, section) {
+        misc.disableExitConfirmation();
+        if (this._id !== e.detail.post.id) {
+            router.replace(
+                '/post/' + e.detail.post.id + '/' + section, null, false);
+        }
+    }
+
+    _evtMerge(e) {
+        this._view.clearMessages();
+        this._view.disableForm();
+        e.detail.post.merge(e.detail.targetPost.id, e.detail.useOldContent)
+            .then(() => {
+                this._view = new PostDetailView({
+                    post: e.detail.targetPost,
+                    section: 'merge',
+                    canMerge: api.hasPrivilege('posts:merge'),
+                });
+                this._view.showSuccess('Post merged.');
+                router.replace(
+                    '/post/' + e.detail.targetPost.id + '/merge', null, false);
+            }, errorMessage => {
+                this._view.showError(errorMessage);
+                this._view.enableForm();
+            });
+    }
+}
+
+module.exports = router => {
+    router.enter(
+        '/post/:id/merge',
+        (ctx, next) => {
+            ctx.controller = new PostDetailController(ctx, 'merge');
+        });
+};

client/js/controllers/post_main_controller.js

@@ -7,26 +7,19 @@ const settings = require('../models/settings.js');
 const Comment = require('../models/comment.js');
 const Post = require('../models/post.js');
 const PostList = require('../models/post_list.js');
-const topNavigation = require('../models/top_navigation.js');
-const PostView = require('../views/post_view.js');
+const PostMainView = require('../views/post_main_view.js');
+const BasePostController = require('./base_post_controller.js');
 const EmptyView = require('../views/empty_view.js');
 
-class PostController {
-    constructor(id, editMode, ctx) {
-        if (!api.hasPrivilege('posts:view')) {
-            this._view = new EmptyView();
-            this._view.showError('You don\'t have privileges to view posts.');
-            return;
-        }
-
-        topNavigation.activate('posts');
-        topNavigation.setTitle('Post #' + id.toString());
+class PostMainController extends BasePostController {
+    constructor(ctx, editMode) {
+        super(ctx);
 
         let parameters = ctx.parameters;
         Promise.all([
-                Post.get(id),
+                Post.get(ctx.parameters.id),
                 PostList.getAround(
-                    id, this._decorateSearchQuery(
+                    ctx.parameters.id, this._decorateSearchQuery(
                         parameters ? parameters.query : '')),
         ]).then(responses => {
             const [post, aroundResponse] = responses;
@@ -36,13 +29,13 @@ class PostController {
             if (parameters.query) {
                 ctx.state.parameters = parameters;
                 const url = editMode ?
-                    '/post/' + id + '/edit' :
-                    '/post/' + id;
+                    '/post/' + ctx.parameters.id + '/edit' :
+                    '/post/' + ctx.parameters.id;
                 router.replace(url, ctx.state, false);
             }
 
             this._post = post;
-            this._view = new PostView({
+            this._view = new PostMainView({
                 post: post,
                 editMode: editMode,
                 prevPostId: aroundResponse.prev ? aroundResponse.prev.id : null,
@@ -72,6 +65,8 @@ class PostController {
                     'feature', e => this._evtFeaturePost(e));
                 this._view.sidebarControl.addEventListener(
                     'delete', e => this._evtDeletePost(e));
+                this._view.sidebarControl.addEventListener(
+                    'merge', e => this._evtMergePost(e));
             }
 
             if (this._view.commentFormControl) {
@@ -128,6 +123,10 @@ class PostController {
             });
     }
 
+    _evtMergePost(e) {
+        router.show('/post/' + e.detail.post.id + '/merge');
+    }
+
     _evtDeletePost(e) {
         this._view.sidebarControl.disableForm();
         this._view.sidebarControl.clearMessages();
@@ -262,7 +261,7 @@ module.exports = router => {
             if (ctx.state.parameters) {
                 Object.assign(ctx.parameters, ctx.state.parameters);
             }
-            ctx.controller = new PostController(ctx.parameters.id, true, ctx);
+            ctx.controller = new PostMainController(ctx, true);
         });
     router.enter(
         '/post/:id/:parameters(.*)?',
@@ -272,6 +271,6 @@ module.exports = router => {
             if (ctx.state.parameters) {
                 Object.assign(ctx.parameters, ctx.state.parameters);
             }
-            ctx.controller = new PostController(ctx.parameters.id, false, ctx);
+            ctx.controller = new PostMainController(ctx, false);
         });
 };

client/js/controls/post_edit_sidebar_control.js

@@ -36,6 +36,7 @@ class PostEditSidebarControl extends events.EventTarget {
             canCreateAnonymousPosts: api.hasPrivilege('posts:create:anonymous'),
             canDeletePosts: api.hasPrivilege('posts:delete'),
             canFeaturePosts: api.hasPrivilege('posts:feature'),
+            canMergePosts: api.hasPrivilege('posts:merge'),
         }));
 
         new ExpanderControl(
@@ -108,6 +109,11 @@ class PostEditSidebarControl extends events.EventTarget {
                 'click', e => this._evtFeatureClick(e));
         }
 
+        if (this._mergeLinkNode) {
+            this._mergeLinkNode.addEventListener(
+                'click', e => this._evtMergeClick(e));
+        }
+
         if (this._deleteLinkNode) {
             this._deleteLinkNode.addEventListener(
                 'click', e => this._evtDeleteClick(e));
@@ -186,6 +192,15 @@ class PostEditSidebarControl extends events.EventTarget {
         }
     }
 
+    _evtMergeClick(e) {
+        e.preventDefault();
+        this.dispatchEvent(new CustomEvent('merge', {
+            detail: {
+                post: this._post,
+            },
+        }));
+    }
+
     _evtDeleteClick(e) {
         e.preventDefault();
         if (confirm('Are you sure you want to delete this post?')) {
@@ -244,7 +259,7 @@ class PostEditSidebarControl extends events.EventTarget {
             detail: {
                 post: this._post,
 
-                safety: this._safetyButtonNodes.legnth ?
+                safety: this._safetyButtonNodes.length ?
                     Array.from(this._safetyButtonNodes)
                         .filter(node => node.checked)[0]
                         .value.toLowerCase() :
@@ -314,6 +329,10 @@ class PostEditSidebarControl extends events.EventTarget {
         return this._formNode.querySelector('.management .feature');
     }
 
+    get _mergeLinkNode() {
+        return this._formNode.querySelector('.management .merge');
+    }
+
     get _deleteLinkNode() {
         return this._formNode.querySelector('.management .delete');
     }

client/js/main.js

@@ -34,7 +34,8 @@ controllers.push(require('./controllers/auth_controller.js'));
 controllers.push(require('./controllers/password_reset_controller.js'));
 controllers.push(require('./controllers/comments_controller.js'));
 controllers.push(require('./controllers/snapshots_controller.js'));
-controllers.push(require('./controllers/post_controller.js'));
+controllers.push(require('./controllers/post_detail_controller.js'));
+controllers.push(require('./controllers/post_main_controller.js'));
 controllers.push(require('./controllers/post_list_controller.js'));
 controllers.push(require('./controllers/post_upload_controller.js'));
 controllers.push(require('./controllers/tag_controller.js'));

client/js/models/post.js

@@ -190,6 +190,31 @@ class Post extends events.EventTarget {
             });
     }
 
+    merge(targetId, useOldContent) {
+        return api.get('/post/' + encodeURIComponent(targetId))
+            .then(response => {
+                return api.post('/post-merge/', {
+                    removeVersion: this._version,
+                    remove: this._id,
+                    mergeToVersion: response.version,
+                    mergeTo: targetId,
+                    replaceContent: useOldContent,
+                });
+            }, response => {
+                return Promise.reject(response);
+            }).then(response => {
+                this._updateFromResponse(response);
+                this.dispatchEvent(new CustomEvent('change', {
+                    detail: {
+                        post: this,
+                    },
+                }));
+                return Promise.resolve();
+            }, response => {
+                return Promise.reject(response.description);
+            });
+    }
+
     setScore(score) {
         return api.put('/post/' + this._id + '/score', {score: score})
             .then(response => {

client/js/util/views.js

@@ -53,35 +53,41 @@ function makeThumbnail(url) {
 
 function makeRadio(options) {
     _imbueId(options);
-    return makeVoidElement(
-        'input',
-        {
-            id: options.id,
-            name: options.name,
-            value: options.value,
-            type: 'radio',
-            checked: options.selectedValue === options.value,
-            disabled: options.readonly,
-            required: options.required,
-        }) +
-    _makeLabel(options, {class: 'radio'});
+    return makeNonVoidElement(
+        'label',
+        {for: options.id},
+        makeVoidElement(
+            'input',
+            {
+                id: options.id,
+                name: options.name,
+                value: options.value,
+                type: 'radio',
+                checked: options.selectedValue === options.value,
+                disabled: options.readonly,
+                required: options.required,
+            }) +
+        makeNonVoidElement('span', {class: 'radio'}, options.text));
 }
 
 function makeCheckbox(options) {
     _imbueId(options);
-    return makeVoidElement(
-        'input',
-        {
-            id: options.id,
-            name: options.name,
-            value: options.value,
-            type: 'checkbox',
-            checked: options.checked !== undefined ?
-                options.checked : false,
-            disabled: options.readonly,
-            required: options.required,
-        }) +
-    _makeLabel(options, {class: 'checkbox'});
+    return makeNonVoidElement(
+        'label',
+        {for: options.id},
+        makeVoidElement(
+            'input',
+            {
+                id: options.id,
+                name: options.name,
+                value: options.value,
+                type: 'checkbox',
+                checked: options.checked !== undefined ?
+                    options.checked : false,
+                disabled: options.readonly,
+                required: options.required,
+            }) +
+        makeNonVoidElement('span', {class: 'checkbox'}, options.text));
 }
 
 function makeSelect(options) {

client/js/views/post_detail_view.js

@@ -0,0 +1,80 @@
+'use strict';
+
+const events = require('../events.js');
+const views = require('../util/views.js');
+const PostMergeView = require('./post_merge_view.js');
+const EmptyView = require('../views/empty_view.js');
+
+const template = views.getTemplate('post-detail');
+
+class PostDetailView extends events.EventTarget {
+    constructor(ctx) {
+        super();
+
+        this._ctx = ctx;
+        ctx.post.addEventListener('change', e => this._evtChange(e));
+        ctx.section = ctx.section || 'summary';
+
+        this._hostNode = document.getElementById('content-holder');
+        this._install();
+    }
+
+    _install() {
+        const ctx = this._ctx;
+        views.replaceContent(this._hostNode, template(ctx));
+
+        for (let item of this._hostNode.querySelectorAll('[data-name]')) {
+            item.classList.toggle(
+                'active', item.getAttribute('data-name') === ctx.section);
+        }
+
+        ctx.hostNode = this._hostNode.querySelector('.post-content-holder');
+        if (ctx.section === 'merge') {
+            if (!this._ctx.canMerge) {
+                this._view = new EmptyView();
+                this._view.showError(
+                    'You don\'t have privileges to merge posts.');
+            } else {
+                this._view = new PostMergeView(ctx);
+                events.proxyEvent(this._view, this, 'select');
+                events.proxyEvent(this._view, this, 'submit', 'merge');
+            }
+
+        } else {
+            // this._view = new PostSummaryView(ctx);
+        }
+
+        views.syncScrollPosition();
+    }
+
+    clearMessages() {
+        this._view.clearMessages();
+    }
+
+    enableForm() {
+        this._view.enableForm();
+    }
+
+    disableForm() {
+        this._view.disableForm();
+    }
+
+    showSuccess(message) {
+        this._view.showSuccess(message);
+    }
+
+    showError(message) {
+        this._view.showError(message);
+    }
+
+    selectPost(post) {
+        this._view.selectPost(post);
+    }
+
+    _evtChange(e) {
+        this._ctx.post = e.detail.post;
+        this._install(this._ctx);
+    }
+}
+
+module.exports = PostDetailView;

client/js/views/post_main_view.js

@@ -13,9 +13,9 @@ const PostEditSidebarControl =
 const CommentListControl = require('../controls/comment_list_control.js');
 const CommentFormControl = require('../controls/comment_form_control.js');
 
-const template = views.getTemplate('post');
+const template = views.getTemplate('post-main');
 
-class PostView {
+class PostMainView {
     constructor(ctx) {
         this._hostNode = document.getElementById('content-holder');
 
@@ -118,4 +118,4 @@ class PostView {
     }
 }
 
-module.exports = PostView;
+module.exports = PostMainView;

client/js/views/post_merge_view.js

@@ -0,0 +1,129 @@
+'use strict';
+
+const config = require('../config.js');
+const events = require('../events.js');
+const views = require('../util/views.js');
+
+const KEY_RETURN = 13;
+const template = views.getTemplate('post-merge');
+const sideTemplate = views.getTemplate('post-merge-side');
+
+class PostMergeView extends events.EventTarget {
+    constructor(ctx) {
+        super();
+
+        this._ctx = ctx;
+        this._post = ctx.post;
+        this._hostNode = ctx.hostNode;
+
+        this._leftPost = ctx.post;
+        this._rightPost = null;
+        views.replaceContent(this._hostNode, template(this._ctx));
+        views.decorateValidator(this._formNode);
+
+        this._refreshLeftSide();
+        this._refreshRightSide();
+
+        this._formNode.addEventListener('submit', e => this._evtSubmit(e));
+    }
+
+    clearMessages() {
+        views.clearMessages(this._hostNode);
+    }
+
+    enableForm() {
+        views.enableForm(this._formNode);
+    }
+
+    disableForm() {
+        views.disableForm(this._formNode);
+    }
+
+    showSuccess(message) {
+        views.showSuccess(this._hostNode, message);
+    }
+
+    showError(message) {
+        views.showError(this._hostNode, message);
+    }
+
+    selectPost(post) {
+        this._rightPost = post;
+        this._refreshRightSide();
+    }
+
+    _refreshLeftSide() {
+        views.replaceContent(
+            this._leftSideNode,
+            sideTemplate(Object.assign({}, this._ctx, {
+                post: this._leftPost,
+                name: 'left',
+                editable: false})));
+    }
+
+    _refreshRightSide() {
+        views.replaceContent(
+            this._rightSideNode,
+            sideTemplate(Object.assign({}, this._ctx, {
+                post: this._rightPost,
+                name: 'right',
+                editable: true})));
+
+        if (this._targetPostFieldNode) {
+            this._targetPostFieldNode.addEventListener(
+                'keydown', e => this._evtTargetPostFieldKeyDown(e));
+        }
+    }
+
+    _evtSubmit(e) {
+        e.preventDefault();
+        const checkedTargetPost = this._formNode.querySelector(
+            '.target-post :checked').value;
+        const checkedTargetPostContent = this._formNode.querySelector(
+            '.target-post-content :checked').value;
+        this.dispatchEvent(new CustomEvent('submit', {
+            detail: {
+                post: checkedTargetPost == 'left' ?
+                    this._rightPost :
+                    this._leftPost,
+                targetPost: checkedTargetPost == 'left' ?
+                    this._leftPost :
+                    this._rightPost,
+                useOldContent: checkedTargetPostContent !== checkedTargetPost,
+            },
+        }));
+    }
+
+    _evtTargetPostFieldKeyDown(e) {
+        const key = e.which;
+        if (key !== KEY_RETURN) {
+            return;
+        }
+        e.target.blur();
+        e.preventDefault();
+        this.dispatchEvent(new CustomEvent('select', {
+            detail: {
+                postId: this._targetPostFieldNode.value,
+            },
+        }));
+    }
+
+    get _formNode() {
+        return this._hostNode.querySelector('form');
+    }
+
+    get _leftSideNode() {
+        return this._hostNode.querySelector('.left-post-container');
+    }
+
+    get _rightSideNode() {
+        return this._hostNode.querySelector('.right-post-container');
+    }
+
+    get _targetPostFieldNode() {
+        return this._formNode.querySelector(
+            '.post-mirror input:not([readonly])[type=text]');
+    }
+}
+
+module.exports = PostMergeView;

config.yaml.dist

@@ -80,6 +80,7 @@ privileges:
     'posts:feature':                moderator
     'posts:delete':                 moderator
     'posts:score':                  regular
+    'posts:merge':                  moderator
     'posts:favorite':               regular
 
     'tags:create':                  regular

server/szurubooru/api/post_api.py

@@ -124,6 +124,23 @@ def delete_post(ctx, params):
     return {}
 
 
+@routes.post('/post-merge/?')
+def merge_posts(ctx, _params=None):
+    source_post_id = ctx.get_param_as_string('remove', required=True) or ''
+    target_post_id = ctx.get_param_as_string('mergeTo', required=True) or ''
+    replace_content = ctx.get_param_as_bool('replaceContent')
+    source_post = posts.get_post_by_id(source_post_id)
+    target_post = posts.get_post_by_id(target_post_id)
+    versions.verify_version(source_post, ctx, 'removeVersion')
+    versions.verify_version(target_post, ctx, 'mergeToVersion')
+    versions.bump_version(target_post)
+    auth.verify_privilege(ctx.user, 'posts:merge')
+    posts.merge_posts(source_post, target_post, replace_content)
+    snapshots.merge(source_post, target_post, ctx.user)
+    ctx.session.commit()
+    return _serialize_post(ctx, target_post)
+
+
 @routes.get('/featured-post/?')
 def get_featured_post(ctx, _params=None):
     post = posts.try_get_featured_post()

server/szurubooru/func/cache.py

@@ -1,14 +1,14 @@
 from datetime import datetime
 
 
-class LruCacheItem(object):
+class LruCacheItem:
     def __init__(self, key, value):
         self.key = key
         self.value = value
         self.timestamp = datetime.utcnow()
 
 
-class LruCache(object):
+class LruCache:
     def __init__(self, length, delta=None):
         self.length = length
         self.delta = delta

server/szurubooru/func/images.py

@@ -14,7 +14,7 @@ _SCALE_FIT_FMT = \
     r'scale=iw*max({width}/iw\,{height}/ih):ih*max({width}/iw\,{height}/ih)'
 
 
-class Image(object):
+class Image:
     def __init__(self, content):
         self.content = content
         self._reload_info()

server/szurubooru/func/posts.py

@@ -440,3 +440,84 @@ def feature_post(post, user):
 def delete(post):
     assert post
     db.session.delete(post)
+
+
+def merge_posts(source_post, target_post, replace_content):
+    assert source_post
+    assert target_post
+    if source_post.post_id == target_post.post_id:
+        raise InvalidPostRelationError('Cannot merge post with itself.')
+
+    def merge_tables(table, anti_dup_func, source_post_id, target_post_id):
+        alias1 = table
+        alias2 = sqlalchemy.orm.util.aliased(table)
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.post_id == source_post_id))
+
+        if anti_dup_func is not None:
+            update_stmt = (update_stmt
+                .where(~sqlalchemy.exists()
+                    .where(anti_dup_func(alias1, alias2))
+                    .where(alias2.post_id == target_post_id)))
+
+        update_stmt = update_stmt.values(post_id=target_post_id)
+        db.session.execute(update_stmt)
+
+    def merge_tags(source_post_id, target_post_id):
+        merge_tables(
+            db.PostTag,
+            lambda alias1, alias2: alias1.tag_id == alias2.tag_id,
+            source_post_id,
+            target_post_id)
+
+    def merge_scores(source_post_id, target_post_id):
+        merge_tables(
+            db.PostScore,
+            lambda alias1, alias2: alias1.user_id == alias2.user_id,
+            source_post_id,
+            target_post_id)
+
+    def merge_favorites(source_post_id, target_post_id):
+        merge_tables(
+            db.PostFavorite,
+            lambda alias1, alias2: alias1.user_id == alias2.user_id,
+            source_post_id,
+            target_post_id)
+
+    def merge_comments(source_post_id, target_post_id):
+        merge_tables(db.Comment, None, source_post_id, target_post_id)
+
+    def merge_relations(source_post_id, target_post_id):
+        alias1 = db.PostRelation
+        alias2 = sqlalchemy.orm.util.aliased(db.PostRelation)
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.parent_id == source_post_id)
+            .where(alias1.child_id != target_post_id)
+            .where(~sqlalchemy.exists()
+                .where(alias2.child_id == alias1.child_id)
+                .where(alias2.parent_id == target_post_id))
+            .values(parent_id=target_post_id))
+        db.session.execute(update_stmt)
+
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.child_id == source_post_id)
+            .where(alias1.parent_id != target_post_id)
+            .where(~sqlalchemy.exists()
+                .where(alias2.parent_id == alias1.parent_id)
+                .where(alias2.child_id == target_post_id))
+            .values(child_id=target_post_id))
+        db.session.execute(update_stmt)
+
+    merge_tags(source_post.post_id, target_post.post_id)
+    merge_comments(source_post.post_id, target_post.post_id)
+    merge_scores(source_post.post_id, target_post.post_id)
+    merge_favorites(source_post.post_id, target_post.post_id)
+    merge_relations(source_post.post_id, target_post.post_id)
+
+    delete(source_post)
+
+    db.session.flush()
+
+    if replace_content:
+        content = files.get(get_post_content_path(source_post))
+        update_post_content(target_post, content)

server/szurubooru/func/tags.py

@@ -223,16 +223,49 @@ def merge_tags(source_tag, target_tag):
     assert target_tag
     if source_tag.tag_id == target_tag.tag_id:
         raise InvalidTagRelationError('Cannot merge tag with itself.')
-    pt1 = db.PostTag
-    pt2 = sqlalchemy.orm.util.aliased(db.PostTag)
 
-    update_stmt = (sqlalchemy.sql.expression.update(pt1)
-        .where(db.PostTag.tag_id == source_tag.tag_id)
-        .where(~sqlalchemy.exists()
-            .where(pt2.post_id == pt1.post_id)
-            .where(pt2.tag_id == target_tag.tag_id))
-        .values(tag_id=target_tag.tag_id))
-    db.session.execute(update_stmt)
+    def merge_posts(source_tag_id, target_tag_id):
+        alias1 = db.PostTag
+        alias2 = sqlalchemy.orm.util.aliased(db.PostTag)
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.tag_id == source_tag_id))
+        update_stmt = (update_stmt
+            .where(~sqlalchemy.exists()
+                .where(alias1.post_id == alias2.post_id)
+                .where(alias2.tag_id == target_tag_id)))
+        update_stmt = update_stmt.values(tag_id=target_tag_id)
+        db.session.execute(update_stmt)
+
+    def merge_relations(table, source_tag_id, target_tag_id):
+        alias1 = table
+        alias2 = sqlalchemy.orm.util.aliased(table)
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.parent_id == source_tag_id)
+            .where(alias1.child_id != target_tag_id)
+            .where(~sqlalchemy.exists()
+                .where(alias2.child_id == alias1.child_id)
+                .where(alias2.parent_id == target_tag_id))
+            .values(parent_id=target_tag_id))
+        db.session.execute(update_stmt)
+
+        update_stmt = (sqlalchemy.sql.expression.update(alias1)
+            .where(alias1.child_id == source_tag_id)
+            .where(alias1.parent_id != target_tag_id)
+            .where(~sqlalchemy.exists()
+                .where(alias2.parent_id == alias1.parent_id)
+                .where(alias2.child_id == target_tag_id))
+            .values(child_id=target_tag_id))
+        db.session.execute(update_stmt)
+
+    def merge_suggestions(source_tag_id, target_tag_id):
+        merge_relations(db.TagSuggestion, source_tag_id, target_tag_id)
+
+    def merge_implications(source_tag_id, target_tag_id):
+        merge_relations(db.TagImplication, source_tag_id, target_tag_id)
+
+    merge_posts(source_tag.tag_id, target_tag.tag_id)
+    merge_suggestions(source_tag.tag_id, target_tag.tag_id)
+    merge_implications(source_tag.tag_id, target_tag.tag_id)
     delete(source_tag)
 
 

server/szurubooru/rest/context.py

@@ -25,7 +25,7 @@ def _param_wrapper(func):
     return wrapper
 
 
-class Context():
+class Context:
     def __init__(self, method, url, headers=None, params=None, files=None):
         self.method = method
         self.url = url

server/szurubooru/search/configs/base_search_config.py

@@ -1,7 +1,7 @@
 from szurubooru.search import tokens
 
 
-class BaseSearchConfig(object):
+class BaseSearchConfig:
     SORT_ASC = tokens.SortToken.SORT_ASC
     SORT_DESC = tokens.SortToken.SORT_DESC
 

server/szurubooru/search/criteria.py

@@ -1,4 +1,4 @@
-class _BaseCriterion(object):
+class _BaseCriterion:
     def __init__(self, original_text):
         self.original_text = original_text
 

server/szurubooru/search/executor.py

@@ -20,7 +20,7 @@ def _get_order(order, default_order):
     return order
 
 
-class Executor(object):
+class Executor:
     '''
     Class for search parsing and execution. Handles plaintext parsing and
     delegates sqlalchemy filter decoration to SearchConfig instances.

server/szurubooru/search/parser.py

@@ -67,7 +67,7 @@ def _parse_sort(value, negated):
     return tokens.SortToken(value, order)
 
 
-class SearchQuery():
+class SearchQuery:
     def __init__(self):
         self.anonymous_tokens = []
         self.named_tokens = []
@@ -82,7 +82,7 @@ class SearchQuery():
             tuple(self.sort_tokens)))
 
 
-class Parser(object):
+class Parser:
     def parse(self, query_text):
         query = SearchQuery()
         for chunk in re.split(r'\s+', (query_text or '').lower()):

server/szurubooru/search/tokens.py

@@ -1,4 +1,4 @@
-class AnonymousToken(object):
+class AnonymousToken:
     def __init__(self, criterion, negated):
         self.criterion = criterion
         self.negated = negated
@@ -16,7 +16,7 @@ class NamedToken(AnonymousToken):
         return hash((self.name, self.criterion, self.negated))
 
 
-class SortToken(object):
+class SortToken:
     SORT_DESC = 'desc'
     SORT_ASC = 'asc'
     SORT_DEFAULT = 'default'
@@ -30,7 +30,7 @@ class SortToken(object):
         return hash((self.name, self.order))
 
 
-class SpecialToken(object):
+class SpecialToken:
     def __init__(self, value, negated):
         self.value = value
         self.negated = negated

server/szurubooru/tests/api/test_post_merging.py

@@ -0,0 +1,89 @@
+from unittest.mock import patch
+import pytest
+from szurubooru import api, db, errors
+from szurubooru.func import posts, snapshots
+
+
+@pytest.fixture(autouse=True)
+def inject_config(config_injector):
+    config_injector({'privileges': {'posts:merge': db.User.RANK_REGULAR}})
+
+
+def test_merging(user_factory, context_factory, post_factory):
+    auth_user = user_factory(rank=db.User.RANK_REGULAR)
+    source_post = post_factory()
+    target_post = post_factory()
+    db.session.add_all([source_post, target_post])
+    db.session.flush()
+    with patch('szurubooru.func.posts.serialize_post'), \
+            patch('szurubooru.func.posts.merge_posts'), \
+            patch('szurubooru.func.snapshots.merge'):
+        api.post_api.merge_posts(
+            context_factory(
+                params={
+                    'removeVersion': 1,
+                    'mergeToVersion': 1,
+                    'remove': source_post.post_id,
+                    'mergeTo': target_post.post_id,
+                },
+                user=auth_user))
+        posts.merge_posts.called_once_with(source_post, target_post)
+        snapshots.merge.assert_called_once_with(
+            source_post, target_post, auth_user)
+
+
+@pytest.mark.parametrize(
+    'field', ['remove', 'mergeTo', 'removeVersion', 'mergeToVersion'])
+def test_trying_to_omit_mandatory_field(
+        user_factory, post_factory, context_factory, field):
+    source_post = post_factory()
+    target_post = post_factory()
+    db.session.add_all([source_post, target_post])
+    db.session.commit()
+    params = {
+        'removeVersion': 1,
+        'mergeToVersion': 1,
+        'remove': source_post.post_id,
+        'mergeTo': target_post.post_id,
+    }
+    del params[field]
+    with pytest.raises(errors.ValidationError):
+        api.post_api.merge_posts(
+            context_factory(
+                params=params,
+                user=user_factory(rank=db.User.RANK_REGULAR)))
+
+
+def test_trying_to_merge_non_existing(
+        user_factory, post_factory, context_factory):
+    post = post_factory()
+    db.session.add(post)
+    db.session.commit()
+    with pytest.raises(posts.PostNotFoundError):
+        api.post_api.merge_posts(
+            context_factory(
+                params={'remove': post.post_id, 'mergeTo': 999},
+                user=user_factory(rank=db.User.RANK_REGULAR)))
+    with pytest.raises(posts.PostNotFoundError):
+        api.post_api.merge_posts(
+            context_factory(
+                params={'remove': 999, 'mergeTo': post.post_id},
+                user=user_factory(rank=db.User.RANK_REGULAR)))
+
+
+def test_trying_to_merge_without_privileges(
+        user_factory, post_factory, context_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    db.session.add_all([source_post, target_post])
+    db.session.commit()
+    with pytest.raises(errors.AuthError):
+        api.post_api.merge_posts(
+            context_factory(
+                params={
+                    'removeVersion': 1,
+                    'mergeToVersion': 1,
+                    'remove': source_post.post_id,
+                    'mergeTo': target_post.post_id,
+                },
+                user=user_factory(rank=db.User.RANK_ANONYMOUS)))

server/szurubooru/tests/conftest.py

@@ -10,7 +10,7 @@ import sqlalchemy
 from szurubooru import config, db, rest
 
 
-class QueryCounter(object):
+class QueryCounter:
     def __init__(self):
         self._statements = []
 
@@ -192,6 +192,30 @@ def comment_factory(user_factory, post_factory):
     return factory
 
 
+@pytest.fixture
+def post_score_factory(user_factory, post_factory):
+    def factory(post=None, user=None, score=1):
+        if user is None:
+            user = user_factory()
+        if post is None:
+            post = post_factory()
+        return db.PostScore(
+            post=post, user=user, score=score, time=datetime(1999, 1, 1))
+    return factory
+
+
+@pytest.fixture
+def post_favorite_factory(user_factory, post_factory):
+    def factory(post=None, user=None):
+        if user is None:
+            user = user_factory()
+        if post is None:
+            post = post_factory()
+        return db.PostFavorite(
+            post=post, user=user, time=datetime(1999, 1, 1))
+    return factory
+
+
 @pytest.fixture
 def read_asset():
     def get(path):

server/szurubooru/tests/func/test_posts.py

@@ -605,3 +605,251 @@ def test_delete(post_factory):
     posts.delete(post)
     db.session.flush()
     assert posts.get_post_count() == 0
+
+
+def test_merge_posts_deletes_source_post(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    db.session.add_all([source_post, target_post])
+    db.session.flush()
+    posts.merge_posts(source_post, target_post, False)
+    db.session.flush()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    post = posts.get_post_by_id(target_post.post_id)
+    assert post is not None
+
+
+def test_merge_posts_with_itself(post_factory):
+    source_post = post_factory()
+    db.session.add(source_post)
+    db.session.flush()
+    with pytest.raises(posts.InvalidPostRelationError):
+        posts.merge_posts(source_post, source_post, False)
+
+
+def test_merge_posts_moves_tags(post_factory, tag_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    tag = tag_factory()
+    tag.posts = [source_post]
+    db.session.add_all([source_post, target_post, tag])
+    db.session.commit()
+    assert source_post.tag_count == 1
+    assert target_post.tag_count == 0
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).tag_count == 1
+
+
+def test_merge_posts_doesnt_duplicate_tags(post_factory, tag_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    tag = tag_factory()
+    tag.posts = [source_post, target_post]
+    db.session.add_all([source_post, target_post, tag])
+    db.session.commit()
+    assert source_post.tag_count == 1
+    assert target_post.tag_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).tag_count == 1
+
+
+def test_merge_posts_moves_comments(post_factory, comment_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    comment = comment_factory(post=source_post)
+    db.session.add_all([source_post, target_post, comment])
+    db.session.commit()
+    assert source_post.comment_count == 1
+    assert target_post.comment_count == 0
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).comment_count == 1
+
+
+def test_merge_posts_moves_scores(post_factory, post_score_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    score = post_score_factory(post=source_post, score=1)
+    db.session.add_all([source_post, target_post, score])
+    db.session.commit()
+    assert source_post.score == 1
+    assert target_post.score == 0
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).score == 1
+
+
+def test_merge_posts_doesnt_duplicate_scores(
+        post_factory, user_factory, post_score_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    user = user_factory()
+    score1 = post_score_factory(post=source_post, score=1, user=user)
+    score2 = post_score_factory(post=target_post, score=1, user=user)
+    db.session.add_all([source_post, target_post, score1, score2])
+    db.session.commit()
+    assert source_post.score == 1
+    assert target_post.score == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).score == 1
+
+
+def test_merge_posts_moves_favorites(post_factory, post_favorite_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    favorite = post_favorite_factory(post=source_post)
+    db.session.add_all([source_post, target_post, favorite])
+    db.session.commit()
+    assert source_post.favorite_count == 1
+    assert target_post.favorite_count == 0
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).favorite_count == 1
+
+
+def test_merge_posts_doesnt_duplicate_favorites(
+        post_factory, user_factory, post_favorite_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    user = user_factory()
+    favorite1 = post_favorite_factory(post=source_post, user=user)
+    favorite2 = post_favorite_factory(post=target_post, user=user)
+    db.session.add_all([source_post, target_post, favorite1, favorite2])
+    db.session.commit()
+    assert source_post.favorite_count == 1
+    assert target_post.favorite_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).favorite_count == 1
+
+
+def test_merge_posts_moves_child_relations(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    related_post = post_factory()
+    source_post.relations = [related_post]
+    db.session.add_all([source_post, target_post, related_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 0
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 1
+
+
+def test_merge_posts_doesnt_duplicate_child_relations(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    related_post = post_factory()
+    source_post.relations = [related_post]
+    target_post.relations = [related_post]
+    db.session.add_all([source_post, target_post, related_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 1
+
+
+def test_merge_posts_moves_parent_relations(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    related_post = post_factory()
+    related_post.relations = [source_post]
+    db.session.add_all([source_post, target_post, related_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 0
+    assert related_post.relation_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 1
+    assert posts.get_post_by_id(related_post.post_id).relation_count == 1
+
+
+def test_merge_posts_doesnt_duplicate_parent_relations(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    related_post = post_factory()
+    related_post.relations = [source_post, target_post]
+    db.session.add_all([source_post, target_post, related_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 1
+    assert related_post.relation_count == 2
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 1
+    assert posts.get_post_by_id(related_post.post_id).relation_count == 1
+
+
+def test_merge_posts_doesnt_create_relation_loop_for_children(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    source_post.relations = [target_post]
+    db.session.add_all([source_post, target_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 0
+
+
+def test_merge_posts_doesnt_create_relation_loop_for_parents(post_factory):
+    source_post = post_factory()
+    target_post = post_factory()
+    target_post.relations = [source_post]
+    db.session.add_all([source_post, target_post])
+    db.session.commit()
+    assert source_post.relation_count == 1
+    assert target_post.relation_count == 1
+    posts.merge_posts(source_post, target_post, False)
+    db.session.commit()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    assert posts.get_post_by_id(target_post.post_id).relation_count == 0
+
+
+def test_merge_posts_replaces_content(
+        post_factory, config_injector, tmpdir, read_asset):
+    config_injector({
+        'data_dir': str(tmpdir.mkdir('data')),
+        'data_url': 'example.com',
+        'thumbnails': {
+            'post_width': 300,
+            'post_height': 300,
+        },
+    })
+    source_post = post_factory()
+    target_post = post_factory()
+    content = read_asset('png.png')
+    db.session.add_all([source_post, target_post])
+    db.session.commit()
+    posts.update_post_content(source_post, content)
+    db.session.flush()
+    assert os.path.exists(os.path.join(str(tmpdir), 'data/posts/1.png'))
+    assert not os.path.exists(os.path.join(str(tmpdir), 'data/posts/2.dat'))
+    assert not os.path.exists(os.path.join(str(tmpdir), 'data/posts/2.png'))
+    posts.merge_posts(source_post, target_post, True)
+    db.session.flush()
+    assert posts.try_get_post_by_id(source_post.post_id) is None
+    post = posts.get_post_by_id(target_post.post_id)
+    assert post is not None
+    assert os.path.exists(os.path.join(str(tmpdir), 'data/posts/1.png'))
+    assert os.path.exists(os.path.join(str(tmpdir), 'data/posts/2.png'))

server/szurubooru/tests/func/test_tags.py

@@ -310,7 +310,7 @@ def test_delete(tag_factory):
     assert db.session.query(db.Tag).count() == 2
 
 
-def test_merge_tags_without_usages(tag_factory):
+def test_merge_tags_deletes_source_tag(tag_factory):
     source_tag = tag_factory(names=['source'])
     target_tag = tag_factory(names=['target'])
     db.session.add_all([source_tag, target_tag])
@@ -322,7 +322,15 @@ def test_merge_tags_without_usages(tag_factory):
     assert tag is not None
 
 
-def test_merge_tags_with_usages(tag_factory, post_factory):
+def test_merge_tags_with_itself(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    db.session.add(source_tag)
+    db.session.flush()
+    with pytest.raises(tags.InvalidTagRelationError):
+        tags.merge_tags(source_tag, source_tag)
+
+
+def test_merge_tags_moves_usages(tag_factory, post_factory):
     source_tag = tag_factory(names=['source'])
     target_tag = tag_factory(names=['target'])
     post = post_factory()
@@ -337,62 +345,7 @@ def test_merge_tags_with_usages(tag_factory, post_factory):
     assert tags.get_tag_by_name('target').post_count == 1
 
 
-def test_merge_tags_with_itself(tag_factory):
-    source_tag = tag_factory(names=['source'])
-    db.session.add(source_tag)
-    db.session.flush()
-    with pytest.raises(tags.InvalidTagRelationError):
-        tags.merge_tags(source_tag, source_tag)
-
-
-def test_merge_tags_with_its_child_relation(tag_factory, post_factory):
-    source_tag = tag_factory(names=['source'])
-    target_tag = tag_factory(names=['target'])
-    source_tag.suggestions = [target_tag]
-    source_tag.implications = [target_tag]
-    post = post_factory()
-    post.tags = [source_tag, target_tag]
-    db.session.add_all([source_tag, post])
-    db.session.flush()
-    tags.merge_tags(source_tag, target_tag)
-    db.session.flush()
-    assert tags.try_get_tag_by_name('source') is None
-    assert tags.get_tag_by_name('target').post_count == 1
-
-
-def test_merge_tags_with_its_parent_relation(tag_factory, post_factory):
-    source_tag = tag_factory(names=['source'])
-    target_tag = tag_factory(names=['target'])
-    target_tag.suggestions = [source_tag]
-    target_tag.implications = [source_tag]
-    post = post_factory()
-    post.tags = [source_tag, target_tag]
-    db.session.add_all([source_tag, target_tag, post])
-    db.session.flush()
-    tags.merge_tags(source_tag, target_tag)
-    db.session.flush()
-    assert tags.try_get_tag_by_name('source') is None
-    assert tags.get_tag_by_name('target').post_count == 1
-
-
-def test_merge_tags_clears_relations(tag_factory):
-    source_tag = tag_factory(names=['source'])
-    target_tag = tag_factory(names=['target'])
-    referring_tag = tag_factory(names=['parent'])
-    referring_tag.suggestions = [source_tag]
-    referring_tag.implications = [source_tag]
-    db.session.add_all([source_tag, target_tag, referring_tag])
-    db.session.flush()
-    assert tags.try_get_tag_by_name('parent').implications != []
-    assert tags.try_get_tag_by_name('parent').suggestions != []
-    tags.merge_tags(source_tag, target_tag)
-    db.session.commit()
-    assert tags.try_get_tag_by_name('source') is None
-    assert tags.try_get_tag_by_name('parent').implications == []
-    assert tags.try_get_tag_by_name('parent').suggestions == []
-
-
-def test_merge_tags_when_target_exists(tag_factory, post_factory):
+def test_merge_tags_doesnt_duplicate_usages(tag_factory, post_factory):
     source_tag = tag_factory(names=['source'])
     target_tag = tag_factory(names=['target'])
     post = post_factory()
@@ -407,6 +360,103 @@ def test_merge_tags_when_target_exists(tag_factory, post_factory):
     assert tags.get_tag_by_name('target').post_count == 1
 
 
+def test_merge_tags_moves_child_relations(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    target_tag = tag_factory(names=['target'])
+    related_tag = tag_factory()
+    source_tag.suggestions = [related_tag]
+    source_tag.implications = [related_tag]
+    db.session.add_all([source_tag, target_tag, related_tag])
+    db.session.commit()
+    assert source_tag.suggestion_count == 1
+    assert source_tag.implication_count == 1
+    assert target_tag.suggestion_count == 0
+    assert target_tag.implication_count == 0
+    tags.merge_tags(source_tag, target_tag)
+    db.session.commit()
+    assert tags.try_get_tag_by_name('source') is None
+    assert tags.get_tag_by_name('target').suggestion_count == 1
+    assert tags.get_tag_by_name('target').implication_count == 1
+
+
+def test_merge_tags_doesnt_duplicate_child_relations(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    target_tag = tag_factory(names=['target'])
+    related_tag = tag_factory()
+    source_tag.suggestions = [related_tag]
+    source_tag.implications = [related_tag]
+    target_tag.suggestions = [related_tag]
+    target_tag.implications = [related_tag]
+    db.session.add_all([source_tag, target_tag, related_tag])
+    db.session.commit()
+    assert source_tag.suggestion_count == 1
+    assert source_tag.implication_count == 1
+    assert target_tag.suggestion_count == 1
+    assert target_tag.implication_count == 1
+    tags.merge_tags(source_tag, target_tag)
+    db.session.commit()
+    assert tags.try_get_tag_by_name('source') is None
+    assert tags.get_tag_by_name('target').suggestion_count == 1
+    assert tags.get_tag_by_name('target').implication_count == 1
+
+
+def test_merge_tags_moves_parent_relations(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    target_tag = tag_factory(names=['target'])
+    related_tag = tag_factory(names=['related'])
+    related_tag.suggestions = [related_tag]
+    related_tag.implications = [related_tag]
+    db.session.add_all([source_tag, target_tag, related_tag])
+    db.session.commit()
+    assert source_tag.suggestion_count == 0
+    assert source_tag.implication_count == 0
+    assert target_tag.suggestion_count == 0
+    assert target_tag.implication_count == 0
+    tags.merge_tags(source_tag, target_tag)
+    db.session.commit()
+    assert tags.try_get_tag_by_name('source') is None
+    assert tags.get_tag_by_name('related').suggestion_count == 1
+    assert tags.get_tag_by_name('related').suggestion_count == 1
+    assert tags.get_tag_by_name('target').suggestion_count == 0
+    assert tags.get_tag_by_name('target').implication_count == 0
+
+
+def test_merge_tags_doesnt_create_relation_loop_for_children(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    target_tag = tag_factory(names=['target'])
+    source_tag.suggestions = [target_tag]
+    source_tag.implications = [target_tag]
+    db.session.add_all([source_tag, target_tag])
+    db.session.commit()
+    assert source_tag.suggestion_count == 1
+    assert source_tag.implication_count == 1
+    assert target_tag.suggestion_count == 0
+    assert target_tag.implication_count == 0
+    tags.merge_tags(source_tag, target_tag)
+    db.session.commit()
+    assert tags.try_get_tag_by_name('source') is None
+    assert tags.get_tag_by_name('target').suggestion_count == 0
+    assert tags.get_tag_by_name('target').implication_count == 0
+
+
+def test_merge_tags_doesnt_create_relation_loop_for_parents(tag_factory):
+    source_tag = tag_factory(names=['source'])
+    target_tag = tag_factory(names=['target'])
+    target_tag.suggestions = [source_tag]
+    target_tag.implications = [source_tag]
+    db.session.add_all([source_tag, target_tag])
+    db.session.commit()
+    assert source_tag.suggestion_count == 0
+    assert source_tag.implication_count == 0
+    assert target_tag.suggestion_count == 1
+    assert target_tag.implication_count == 1
+    tags.merge_tags(source_tag, target_tag)
+    db.session.commit()
+    assert tags.try_get_tag_by_name('source') is None
+    assert tags.get_tag_by_name('target').suggestion_count == 0
+    assert tags.get_tag_by_name('target').implication_count == 0
+
+
 def test_create_tag(fake_datetime):
     with patch('szurubooru.func.tags.update_tag_names'), \
             patch('szurubooru.func.tags.update_tag_category_name'), \