Use tags to mark specific commits
Git allows you to attach tags to commits to mark certain points in the project history so that you can refer to them in the future. For example, you can tag a commit that corresponds to a release version, instead of creating a branch to capture a release snapshot.
Assign a tag to a commit
Assign an annotated tag to a commit
Meta-data for annotated tags contains the name of the user who created them, so they allow you to check who placed them.
From the main menu, choose VCS | Git | Tag
In the Tag dialog that opens, under Git Root, select the path to the local repository in which you want to tag a commit, and specify the name of the new tag.
In the Commit field, specify the commit that you want to tag. You can enter the commit hash, or use an expression, for example:
<branch>~<number of commits backwards between the latest commit (HEAD) and the required commit>(Refer to Git commit naming conventions for details).
Enter some comment in the Message field to create an annotated tag (if it's empty, a regular tag will be created).
Click Create Tag.
Reassign an existing tag
If you've placed a tag on a wrong commit, and want to reassign it (for example, to indicate a commit for a release version), do the following:
From the main menu, choose VCS | Git | Tag.
In the Tag dialog, in the Tag Name field specify the name of an already existing tag that you want to reassign.
Select the Force option.
In the Commit field, specify the commit where the tag shall be moved and click Create Tag.
Jump to a tagged commit
Click the Go To Hash/Branch/Tag icon on the toolbar, or press Ctrl+F.
Enter the tag name (code completion suggests tag names as you type) and press Enter.
Check out a tagged commit
Suppose you marked a commit that corresponds to a release version with a tag, and now you want to review the snapshot of your project at that point in time. You can do this by checking out a tagged commit. Do one of the following:
Locate the tagged commit that you want to checkout, right-click it and select Checkout Revision from the context menu.
Invoke the branches popup, click Checkout Tag or Revision and type in the tag name (RubyMine provides a list of matching tags and revisions as you type).
Note that this operation results in a detached HEAD, which means you are no longer in any branch. You can use this snapshot for inspection and experiments. However, if you want to commit changes on top of this snapshot, you will need to create a branch.
Delete a tag
Locate a tagged commit, right-click it and select Tag <tag_name> | Delete from the context menu.