Add support for a "group-by-task" output format

[jonathanio]

Description

When working with output: group in multi-cmd tasks, the grouping is at a per-cmd level, rather than at the level of each individual task. I've been doing a lot of refactoring recently, with some of my Taskfiles going from something like:

cmds:
  - cmd: |-
      if test; then
        run-cmd
        status=${?}
        echo "${status}" > .status-code
        if [[ ${?} -ne 0 ]]; then
          echo "(red)Failed!"
          exit "${status}"
        else
          echo "(green)Passed"
        fi

to:

cmds:
  - defer: "{{ if .EXIT_CODE }}echo '(red)Failed!'{{ end }}"
  - defer: "echo '{{ default 0 .EXIT_CODE }}' > .status-code"
  - cmd: run-cmd
  - cmd: echo "(green)Passed"

Which is a fair bit cleaner, and I can also then run multiple cmd blocks within the error/exit handling steps, which is nice.

However, when running it within a GitHub Workflow using the --output-group and --output-group-{begin,end} arguments, while the first outputs as a single group, the second runs with lots of groups:

::group::test
This is the output from run-cmd.
::endgroup::
::group::test
Passed!
::endgroup::

When I have multiple tasks running in parallel as well through deps, I get multiple groups for multiple tasks all interleaving as well, which makes the output complex to review, for example (as a real-world example):

::group::terraform:workspace
Workspace "production" is active.
Additional arguments provided:
  -var-file=terraform/variables/production.tfvars
::endgroup::
::group::terraform:init
Validated the backend prefix for GCS.
::endgroup::
::group::tflint:init
All plugins are already installed
::endgroup::
::group::tflint:init
Completed
::endgroup::
::group::terraform:fmt
Passed
::endgroup::
::group::tflint
Passed
::endgroup::
::group::terraform:init
Initializing the backend...

Successfully configured the backend "gcs"! Terraform will automatically
use this backend unless the backend configuration changes.

Initializing provider plugins...
- Finding goauthentik/authentik versions matching "2026.5.0"...
- Finding integrations/github versions matching "6.13.0"...
- Finding hashicorp/vault versions matching "5.10.1"...
- Using goauthentik/authentik v2026.5.0 from the shared cache directory
- Using integrations/github v6.13.0 from the shared cache directory
- Using hashicorp/vault v5.10.1 from the shared cache directory

Terraform has been successfully initialized!
::endgroup::
::group::terraform:init
Switched to workspace "production".
::endgroup::
::group::terraform:init
Completed
::endgroup::

It would be good if we could group not only by cmd but also by task. I don't know whether something like a group-by-task output option might be good, or a --output-group-by-task/TASK_OUTPUT_BY_TASK option as a way to get Taskfile to collate all the outputs from each cmd within a task.

There seems to be a bit of overlap with #2872 too, if the multiple groups within GitLab are caused by multiple cmds within the task creating multiple identical groups, like in this case. If there is an intention to create an output type for Gitlab, then maybe the --output-group-by-task might be the better option for this case?

[trulede]

@jonathanio AFAIR grouping is per task, something else may be a factor. Please provide a complete (minimal) taskfile that reproduces this problem. Also the command you use to run task, in case that's a factor.

[jonathanio]

No problem. The code itself is all open-source as part of my homelab stuff currently, and can be seen in files like n3tuk/infra-vault/.task/terraform.yaml, but I've cleaned up some of the tasks which are used in the real-world example here so that they just output the commands that would, in theory, be run:

---
version: 3

output:
  group:
    begin: '::group::{{ .TASK }}'
    end: '::endgroup::'

vars:
  default: "production"
  workspaces:
    - "production"
    - "staging"
    - "development"

tasks:
  terraform:switch:
    silent: true
    run: once
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - cmd: echo "\$ mkdir -p '{{ default "../" .ROOT_DIR }}/.bin'"
      - cmd: echo "\$ tfswitch --bin '{{ default "../" .ROOT_DIR }}/.bin/terraform' 2>&1 | ( grep -v 'PATH=' || true )"
      - cmd: echo -e '\e[0;32mCompleted\e[0m'

  tflint:init:
    internal: true
    silent: true
    run: when_changed
    cmds:
      - cmd: echo "\$ tflint --config '{{ .ROOT_DIR }}/.tflint.hcl' --init"
      - cmd: echo -e '\e[0;32mCompleted\e[0m'

  tflint:
    deps:
      - task: tflint:init
      - task: terraform:fmt
    silent: true
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - cmd: echo "\$ tflint --config '{{ .ROOT_DIR }}/.tflint.hcl'"
      - cmd: echo -e '\e[0;32mPassed\e[0m'

  terraform:fmt:
    silent: true
    deps:
      - task: terraform:switch
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform fmt -no-color"
      - cmd: echo -e '\e[0;32mPassed\e[0m'

  terraform:workspace:
    silent: true
    run: once
    vars:
      workspace: production
    cmds:
      - cmd: |-
          case '{{ .workspace }}' in
            {{ .workspaces | join "|" }}) ;;
            *)
              echo >&2 'The workspace selected ({{ .workspace }}) is invalid.'
              echo >&2 'Terraform workspaces must be one of:'
              echo >&2 '  - {{ .workspaces | join "\n  - " }}'
              echo >&2 'Please run `task {{ .TASK }}:{{ .default }}` to reset.'
              exit 1
              ;;
          esac
      - cmd: |-
          echo -e 'Workspace "{{ .workspace }}" is active.'

  terraform:init:
    internal: true
    silent: true
    run: when_changed
    deps:
      - task: terraform:workspace
      - task: terraform:switch
    vars:
      workspace: production
    env:
      TF_IN_AUTOMATION: "true"
      TF_INPUT: "false"
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - defer: echo "\$ echo -n '{{ default "0" .EXIT_CODE }}' > '.terraform/init'"
      - cmd: echo "\$ mkdir -p .terraform"
      - cmd: echo "\$ rm -f terraform.tfplan"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform init -upgrade -no-color |& tee '.terraform/init.log'"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform workspace select -or-create=true -no-color '{{ .workspace }}' |& tee -a '.terraform/init.log'"
      - cmd: echo -e '\e[0;32mCompleted\e[0m'

  terraform:get:
    silent: true
    deps:
      - task: terraform:init
    vars:
      workspace: production
    env:
      TF_IN_AUTOMATION: "true"
      TF_INPUT: "false"
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform get -update -no-color"
      - cmd: echo -e '\e[0;32mPassed\e[0m'

  terraform:validate:
    silent: true
    deps:
      - task: terraform:init
      - task: terraform:get
    vars:
      workspace: "production"
    env:
      TF_IN_AUTOMATION: "true"
      TF_INPUT: "false"
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - defer: echo "\$ echo -n '{{ default "0" .EXIT_CODE }}' > '.terraform/validate'"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform validate -no-color"
      - cmd: echo -e '\e[0;32mPassed\e[0m'

  terraform:plan:
    silent: true
    deps:
      - task: terraform:validate
      - task: tflint
    vars:
      workspace: production
    env:
      TF_IN_AUTOMATION: "true"
      TF_INPUT: "false"
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - defer: echo "\$ echo -n '{{ default "0" .EXIT_CODE }}' > '.terraform/plan'"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform plan -no-color{{ .arguments }} -out=terraform.tfplan |& tee '.terraform/plan.log'"
      - cmd: touch terraform.tfplan
      - cmd: echo -e '\e[0;32mCompleted\e[0m'
    generates:
      - terraform.tfplan
    status:
      - test -f terraform.tfplan

  terraform:apply:
    silent: true
    sources:
      - terraform.tfplan
    deps:
      - task: terraform:workspace
      - task: terraform:plan
    env:
      TF_IN_AUTOMATION: "true"
      TF_INPUT: "false"
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - defer: echo "\$ rm -f terraform.tfplan"
      - cmd: echo "\$ {{ .ROOT_DIR }}/.bin/terraform apply -no-color terraform.tfplan |& tee '.terraform/apply.log'"
      - cmd: echo -e '\e[0;32mCompleted\e[0m'

  terraform:clean:
    run: once
    silent: true
    cmds:
      - defer: "{{ if .EXIT_CODE }}echo -e '\e[1;31mFailed\e[0m'{{ end }}"
      - cmd: rm -f terraform.tfplan
      - cmd: echo -e '\e[0;32mCompleted\e[0m'

which gives me the following output:

$ task --version
3.52.0
$ task terraform:plan
::group::tflint:init
$ tflint --config '/home/jonathan/tmp/taskfile/.tflint.hcl' --init
::endgroup::
::group::terraform:switch
$ mkdir -p '/home/jonathan/tmp/taskfile/.bin'
::endgroup::
::group::tflint:init
Completed
::endgroup::
::group::terraform:switch
$ tfswitch --bin '/home/jonathan/tmp/taskfile/.bin/terraform' 2>&1 | ( grep -v 'PATH=' || true )
::endgroup::
::group::terraform:workspace
Workspace "production" is active.
::endgroup::
::group::terraform:switch
Completed
::endgroup::
::group::terraform:fmt
$ /home/jonathan/tmp/taskfile/.bin/terraform fmt -no-color
::endgroup::
::group::terraform:init
$ mkdir -p .terraform
::endgroup::
::group::terraform:init
$ rm -f terraform.tfplan
::endgroup::
::group::terraform:fmt
Passed
::endgroup::
::group::terraform:init
$ /home/jonathan/tmp/taskfile/.bin/terraform init -upgrade -no-color |& tee '.terraform/init.log'
::endgroup::
::group::tflint
$ tflint --config '/home/jonathan/tmp/taskfile/.tflint.hcl'
::endgroup::
::group::terraform:init
$ /home/jonathan/tmp/taskfile/.bin/terraform workspace select -or-create=true -no-color 'production' |& tee -a '.terraform/init.log'
::endgroup::
::group::tflint
Passed
::endgroup::
::group::terraform:init
Completed
::endgroup::
::group::terraform:init
$ echo -n '0' > '.terraform/init'
::endgroup::
::group::terraform:get
$ /home/jonathan/tmp/taskfile/.bin/terraform get -update -no-color
::endgroup::
::group::terraform:get
Passed
::endgroup::
::group::terraform:validate
$ /home/jonathan/tmp/taskfile/.bin/terraform validate -no-color
::endgroup::
::group::terraform:validate
Passed
::endgroup::
::group::terraform:validate
$ echo -n '0' > '.terraform/validate'
::endgroup::
::group::terraform:plan
$ /home/jonathan/tmp/taskfile/.bin/terraform plan -no-color -out=terraform.tfplan |& tee '.terraform/plan.log'
::endgroup::
::group::terraform:plan
Completed
::endgroup::
::group::terraform:plan
$ echo -n '0' > '.terraform/plan'
::endgroup::

Hopefully that'll give you an idea of what's going on. 😄

[trulede]

@jonathanio OK ...

version: '3'

output:
  group:
    begin: '::group::{{.TASK}}'
    end: '::endgroup::'

tasks:
  default:
    cmds:
      - echo 'Hello, World!'
      - echo 'fuu'
    silent: true

which gives

 task -d ISSUES/3000/
::group::default
Hello, World!
::endgroup::
::group::default
fuu
::endgroup::

Although I think its working as intended, its certainly not what I would expect.

[trulede]

@jonathanio you might delete or shorten you other long comment, to keep the issue focused 🙈

I find it weird to have a group for a task, which is clearly the case (as the task name is used in the group), but then have a group emitted per command of that task. So I don't know if its working as intended, or a defect/bug that no one ever cared about. But since no one ever complained before ...