Features used to implement the examples

• Copy parsed text to a field
• Read fields from linked issues or sub-tasks
• Read field from issues returned by JQL query or issue list
• Write field on linked issues or sub-tasks
• Update issue fields

Multi Valued fields are fields that allow you to select more than one item:

• Checkboxes
• Select List (multiple choices)
• User Picker (multiple users)
• Group Picker (multiple groups)
• Version Picker (multiple versions)
• Fixed versions
• Affected versions
• Labels
• Components
• Request Participants
• Issue Picker
• Insight - Asset Management for Jira's Multi Select

You can use operators + and - to add or remove lone or set of items from Multi Valued fields.

Adding/Removing values from Current issue or Parent issue

• We use post-function Copy parsed text to a field to compose the text with operators + and -, and copy it into a multi-valued field of current issue or parent issue (in the case of sub-tasks).

Adding/Removing values from other issues

• To add or remove a single item or a set items from a multi-valued fields in other issues (linked issues, sub-tasks, or issues returned by a JQL query) different from current issue, we use any of the following post-functions:
  
  • Write field on linked issues or sub-tasks
  • Update issue fields

Adding and removing values in a single post-function

A string like + item_1, item_2, item_3, - item_4, item_5 will add items 1, 2, 3 and remove items 4, 5. You can also inject field codes in the string, and they will be replaced by its corresponding values when parsed by post-function at run time. 

Example 1: Remove "Affects Version/s" from "Fix Version/s" in current issue

Since we are setting a field in current issue, we can do it in a single step using post-function Copy parsed text to a field with the following configuration:

Text to be parsed is: - %{00077}

Note that:

• %{00077} is field code for "Affects Version/s"

Once configured, the transition looks like this:

Example 2: Add components in sub-tasks to components in parent issue

We will explain 2 different configurations to implement this same behavior.

Use post-function Read fields from linked issues or sub-tasks to read Components from sub-tasks and write it into Ephemeral string 1 virtual field: 

Use post-function Copy parsed text to a field to compose string with operator + and Components of sub-tasks read in previous step and write it into main issue's field Components: 

Text to be parsed is: + %{00061}

Note that:

•  %{00061} is field code for "Ephemeral string 1"

Once configured, the transition looks like this:

Alternative implementation

Using one single post-function, use post-function Copy parsed text to a field with the following configuration: 

Text to be parsed: "+ " + toString(fieldValue(%{00094}, subtasks()))

Once configured, the transition looks like this:

Example 3: Remove reporters of blocking and cloned issues from a "Multi User" field called "Team"

We will explain 2 different configurations to implement this same behavior:

Use post-function Read fields from linked issues or sub-tasks to read field Reporter from linked issues and write it into Ephemeral string 1: 

Use post-function Copy parsed text to a field to compose string with operator - and Reporter previously read in step 1 and write it into Multi User field Team: 

Text to be parsed is: - %{00061}

Note that:

•  %{00061} is field code for "Ephemeral string 1"

Once configured, the transition looks like this:

Alternative implementation

Using one single post-function,use post-function Copy parsed text to a field with the following configuration: 

Text to be parsed: "- " + toString(fieldValue(%{00006}, linkedIssues("is blocked by, is cloned by")))

Once configured, the transition looks like this: