# Discussions

The ability to contribute conversationally is offered throughout GitLab.

You can leave a comment in the following places:

- issues
- merge requests
- snippets
- commits
- commit diffs

The comment area supports [Markdown] and [quick actions]. One can edit their
own comment at any time, and anyone with [Maintainer access level][permissions] or
higher can also edit a comment made by someone else.

You could also reply to the notification email in order to reply to a comment,
provided that [Reply by email] is configured by your GitLab admin. This also
supports [Markdown] and [quick actions] as if replied from the web.

Apart from the standard comments, you also have the option to create a comment
in the form of a resolvable or threaded discussion.

## Resolvable discussions

> **Notes:**
> - The main feature was [introduced][ce-5022] in GitLab 8.11.
> - Resolvable discussions can be added only to merge request diffs.

Discussion resolution helps keep track of progress during planning or code review.
Resolving comments prevents you from forgetting to address feedback and lets you
hide discussions that are no longer relevant.

!["A discussion between two people on a piece of code"][discussion-view]

Comments and discussions can be resolved by anyone with at least Developer
access to the project or the author of the merge request.

### Commit discussions in the context of a merge request

> [Introduced][ce-31847] in GitLab 10.3.

For reviewers with commit-based workflow, it may be useful to add discussions to
specific commit diffs in the context of a merge request. These discussions will
persist through a commit ID change when:

- force-pushing after a rebase
- amending a commit

To create a commit diff discussion:

1. Navigate to the merge request **Commits** tab. A list of commits that
   constitute the merge request will be shown.

    ![Merge request commits tab](img/merge_request_commits_tab.png)

1. Navigate to a specific commit, click on the **Changes** tab (where you
   will only be presented diffs from the selected commit), and leave a comment.

    ![Commit diff discussion in merge request context](img/commit_comment_mr_context.png)

1. Any discussions created this way will be shown in the merge request's
   **Discussions** tab and are resolvable.

    ![Merge request Discussions tab](img/commit_comment_mr_discussions_tab.png)

Discussions created this way will only appear in the original merge request
and not when navigating to that commit under your project's
**Repository > Commits** page.

TIP: **Tip:**
When a link of a commit reference is found in a discussion inside a merge
request, it will be automatically converted to a link in the context of the
current merge request.

### Jumping between unresolved discussions

When a merge request has a large number of comments it can be difficult to track
what remains unresolved. You can jump between unresolved discussions with the
Jump button next to the Reply field on a discussion.

You can also jump to the first unresolved discussion from the button next to the
resolved discussions tracker.

!["3/4 discussions resolved"][discussions-resolved]

### Marking a comment or discussion as resolved

You can mark a discussion as resolved by clicking the **Resolve discussion**
button at the bottom of the discussion.

!["Resolve discussion" button][resolve-discussion-button]

Alternatively, you can mark each comment as resolved individually.

!["Resolve comment" button][resolve-comment-button]

### Move all unresolved discussions in a merge request to an issue

> [Introduced][ce-8266] in GitLab 9.1

To continue all open discussions from a merge request in a new issue, click the
**Resolve all discussions in new issue** button.

![Open new issue for all unresolved discussions](img/btn_new_issue_for_all_discussions.png)

Alternatively, when your project only accepts merge requests [when all discussions
are resolved](#only-allow-merge-requests-to-be-merged-if-all-discussions-are-resolved),
there will be an **open an issue to resolve them later** link in the merge
request widget.

![Link in merge request widget](img/resolve_discussion_open_issue.png)

This will prepare an issue with its content referring to the merge request and
the unresolved discussions.

![Issue mentioning discussions in a merge request](img/preview_issue_for_discussions.png)

Hitting **Submit issue** will cause all discussions to be marked as resolved and
add a note referring to the newly created issue.

![Mark discussions as resolved notice](img/resolve_discussion_issue_notice.png)

You can now proceed to merge the merge request from the UI.

### Moving a single discussion to a new issue

> [Introduced][ce-8266] in GitLab 9.1

To create a new issue for a single discussion, you can use the **Resolve this
discussion in a new issue** button.

![Create issue for discussion](img/new_issue_for_discussion.png)

This will direct you to a new issue prefilled with the content of the
discussion, similar to the issues created for delegating multiple
discussions at once. Saving the issue will mark the discussion as resolved and
add a note to the merge request discussion referencing the new issue.

![New issue for a single discussion](img/preview_issue_for_discussion.png)

### Only allow merge requests to be merged if all discussions are resolved

> [Introduced][ce-7125] in GitLab 8.14.

You can prevent merge requests from being merged until all discussions are
resolved.

Navigate to your project's settings page, select the
**Only allow merge requests to be merged if all discussions are resolved** check
box and hit **Save** for the changes to take effect.

![Only allow merge if all the discussions are resolved settings](img/only_allow_merge_if_all_discussions_are_resolved.png)

From now on, you will not be able to merge from the UI until all discussions
are resolved.

![Only allow merge if all the discussions are resolved message](img/only_allow_merge_if_all_discussions_are_resolved_msg.png)

### Automatically resolve merge request diff discussions when they become outdated

> [Introduced][ce-14053] in GitLab 10.0.

You can automatically resolve merge request diff discussions on lines modified
with a new push.

Navigate to your project's settings page, select the **Automatically resolve
merge request diffs discussions on lines changed with a push** check box and hit
**Save** for the changes to take effect.

![Automatically resolve merge request diff discussions when they become outdated](img/automatically_resolve_outdated_discussions.png)

From now on, any discussions on a diff will be resolved by default if a push
makes that diff section outdated. Discussions on lines that don't change and
top-level resolvable discussions are not automatically resolved.

## Commit discussions

You can add comments and discussion threads to a particular commit under your
project's **Repository > Commits**.

CAUTION: **Attention:**
Discussions created this way will be lost if the commit ID changes after a
force push.

## Threaded discussions

> [Introduced][ce-7527] in GitLab 9.1.

While resolvable discussions are only available to merge request diffs,
discussions can also be added without a diff. You can start a specific
discussion which will look like a thread, on issues, commits, snippets, and
merge requests.

To start a threaded discussion, click on the **Comment** button toggle dropdown,
select **Start discussion** and click **Start discussion** when you're ready to
post the comment.

![Comment type toggle](img/comment_type_toggle.gif)

This will post a comment with a single thread to allow you to discuss specific
comments in greater detail.

![Discussion comment](img/discussion_comment.png)

## Image discussions

> [Introduced][ce-14061] in GitLab 10.1.

Sometimes a discussion is revolved around an image. With image discussions,
you can easily target a specific coordinate of an image and start a discussion
around it. Image discussions are available in merge requests and commit detail views.

To start an image discussion, hover your mouse over the image. Your mouse pointer
should convert into an icon, indicating that the image is available for commenting.
Simply click anywhere on the image to create a new discussion.

![Start image discussion](img/start_image_discussion.gif)

After you click on the image, a comment form will be displayed that would be the start
of your discussion. Once you save your comment, you will see a new badge displayed on
top of your image. This badge represents your discussion.

>**Note:**
This discussion badge is typically associated with a number that is only used as a visual
reference for each discussion. In the merge request discussion tab,
this badge will be indicated with a comment icon since each discussion will render a new
image section.

Image discussions also work on diffs that replace an existing image. In this diff view
mode, you can toggle the different view modes and still see the discussion point badges.

| 2-up | Swipe | Onion Skin |
| :-----------: | :----------: | :----------: |
| ![2-up view](img/two_up_view.png) | ![swipe view](img/swipe_view.png) | ![onion skin view](img/onion_skin_view.png) |

Image discussions also work well with resolvable discussions. Resolved discussions
on diffs (not on the merge request discussion tab) will appear collapsed on page
load and will have a corresponding badge counter to match the counter on the image.

![Image resolved discussion](img/image_resolved_discussion.png)

## Lock discussions

> [Introduced][ce-14531] in GitLab 10.1.

For large projects with many contributors, it may be useful to stop discussions
in issues or merge requests in these scenarios:

- The project maintainer has already resolved the discussion and it is not helpful
for continued feedback. The project maintainer has already directed new conversation
to newer issues or merge requests.
- The people participating in the discussion are trolling, abusive, or otherwise
being unproductive.

In these cases, a user with Maintainer permissions or higher in the project can lock (and unlock)
an issue or a merge request, using the "Lock" section in the sidebar:

| Unlock | Lock |
| :-----------: | :----------: |
| ![Turn off discussion lock](img/turn_off_lock.png) | ![Turn on discussion lock](img/turn_on_lock.png) |

System notes indicate locking and unlocking.

![Discussion lock system notes](img/discussion_lock_system_notes.png)

In a locked issue or merge request, only team members can add new comments and
edit existing comments. Non-team members are restricted from adding or editing comments.

| Team member | Non-team member |
| :-----------: | :----------: |
| ![Comment form member](img/lock_form_member.png) | ![Comment form non-member](img/lock_form_non_member.png) |

Additionally locked issues can not be reopened.

## Filtering notes

> [Introduced](https://gitlab.com/gitlab-org/gitlab-ce/issues/26723) in GitLab 11.5. 

For issues with many comments like activity notes and user comments, sometimes 
finding useful information can be hard. There is a way to filter comments from single notes and discussions for merge requests and issues.  

From a merge request's **Discussion** tab, or from an epic/issue overview, find the filter's dropdown menu on the right side of the page, from which you can choose one of the following options:

- **Show all activity**: displays all user comments and system notes
(issue updates, mentions from other issues, changes to the description, etc).
- **Show comments only**: only displays user comments in the list.
- **Show history only**: only displays activity notes. 

![Notes filters dropdown options](img/index_notes_filters.png)

Once you select one of the filters in a given issue or MR, GitLab will save
your preference, so that it will persist when you visit the same page again
from any device you're logged into.

## Suggest Changes

> [Introduced](https://gitlab.com/gitlab-org/gitlab-ce/issues/18008) in GitLab 11.6.

As a reviewer, you're able to suggest code changes with a simple 
markdown syntax in Merge Request Diff discussions. Then, the
Merge Request author (or other users with appropriate 
[permission](../permissions.md)) is able to apply these
suggestions with a click, which will generate a commit in 
the Merge Request authored by the user that applied them.

1. Choose a line of code to be changed, add a new comment, then click
on the **Insert suggestion** icon in the toolbar:

    ![Add a new comment](img/insert_suggestion.png)
    
    > **Note:**
    The suggestion will only affect the commented line. Multi-line
    suggestions are currently not supported. Will be introduced by 
    [#53310](https://gitlab.com/gitlab-org/gitlab-ce/issues/53310).

1. In the comment, add your suggestion to the pre-populated code block:

    ![Add a suggestion into a code block tagged properly](img/make_suggestion.png)

1. Click **Comment**.

    The suggestions in the comment can be applied by the merge request author
    directly from the merge request:

    ![Apply suggestions](img/suggestion.png)

    > **Note:**
    Discussions are _not_ automatically resolved. Will be introduced by 
    [#54405](https://gitlab.com/gitlab-org/gitlab-ce/issues/54405).
    
Once the author applies a suggestion, it will be marked with the **Applied** label,
and GitLab will create a new commit with the message `Apply suggestion to <file-name>`
and push the suggested change directly into the codebase in the merge request's branch.
[Developer permission](../permissions.md) is required to do so.

> **Note:**
Custom commit messages will be introduced by
[#54404](https://gitlab.com/gitlab-org/gitlab-ce/issues/54404).

[ce-5022]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5022
[ce-7125]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7125
[ce-7527]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7527
[ce-7180]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7180
[ce-8266]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8266
[ce-14053]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/14053
[ce-14061]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/14061
[ce-14531]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/14531
[ce-31847]: https://gitlab.com/gitlab-org/gitlab-ce/issues/31847
[resolve-discussion-button]: img/resolve_discussion_button.png
[resolve-comment-button]: img/resolve_comment_button.png
[discussion-view]: img/discussion_view.png
[discussions-resolved]: img/discussions_resolved.png
[markdown]: ../markdown.md
[quick actions]: ../project/quick_actions.md
[permissions]: ../permissions.md
[Reply by email]: ../../administration/reply_by_email.md
