argo-workflows: Error with expr from parameter output another step

Checklist

• Double-checked my configuration.
• Tested using the latest version.
• Used the Emissary executor.

Summary

What happened/what you expected to happen?

When on a when field add an expr with output task I get the next error:

Failed: invalid spec: templates.main when doesn’t support ‘expr’ expression ‘{{=’. ‘When’ expression is only support govaluate format {{

the expr I’m using is:

when: “{{=jsonpath(tasks.checkout.outputs.parameters.custom_config, ‘$.steps.test_unit.skip’)}}”

However when I use and input parameter with expr everything works correctly, but I don’t have use an input parameter because, I need use the output parameter to another task and I get a json file.

when: “{{=inputs.parameters.BRANCH == ‘false’}}”

Which this expr works correctly

What version are you running?

Argo-workflows: 3.3.6 Kubernetes: 1.22.9

Diagnostics

Paste the smallest workflow that reproduces the bug. We must be able to run the workflow.

apiVersion: argoproj.io/v1alpha1
kind: WorkflowTemplate
metadata:
  name: example
  entrypoint: main
  templates:
    - name: main
      inputs:
        parameters:
          - name: URL
          - name: BRANCH 
      dag:
        tasks:
        - name: checkout
          templateRef:
            name: checkout
            template: main
          arguments:
            parameters:
              - name: git_ssh_url
                value: "git@{{= sprig.replace('net/', 'net:', sprig.substr( 8, -1, inputs.parameters.URL)) }}"
              - name: BRANCH
                value: "{{inputs.parameters.BRANCH}}"
...
...
        - name: test-unit
          templateRef:
            name: unit-test
            template: node-web
          arguments:
            parameters:
              - name: PROJECT_NAME
                value: "{{workflow.parameters.PROJECT_NAME}}"
# Get value for testing
              - name: SKIP
                value: "{{=jsonpath(tasks.checkout.outputs.parameters.custom_config, '$.steps.test_unit.skip')}}"
          when: "{{=jsonpath(tasks.checkout.outputs.parameters.custom_config, '$.steps.test_unit.skip') == 'false'}}"

...

kubectl logs -n argo-workflows deploy/workflow-controller | grep example-db6tm

# If the workflow's pods have not been created, you can skip the rest of the diagnostics.

# The workflow's pods that are problematic:
kubectl get pod -o yaml -l workflows.argoproj.io/workflow=example-db6tm,workflow.argoproj.io/phase!=Succeeded

# Logs from in your workflow's wait container, something like:
kubectl logs -c wait -l workflows.argoproj.io/workflow=example-db6tm,workflow.argoproj.io/phase!=Succeeded
time="2022-06-03T20:18:11.654Z" level=info msg="Processing workflow" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.789Z" level=info msg="Updated phase  -> Failed" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.789Z" level=info msg="Updated message  -> invalid spec: templates.main when doesn't support 'expr' expression '{{='. 'When' expression is only support govaluate format {{" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.789Z" level=info msg="Marking workflow completed" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.789Z" level=info msg="Marking workflow as pending archiving" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.790Z" level=error msg="Unable to set ExecWorkflow" error="templates.main when doesn't support 'expr' expression '{{='. 'When' expression is only support govaluate format {{" namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.790Z" level=info msg="Checking daemoned children of " namespace=argo-events workflow=example-db6tm
time="2022-06-03T20:18:11.795Z" level=info msg="cleaning up pod" action=deletePod key=argo-events/example-db6tm-1340600742-agent/deletePod
time="2022-06-03T20:18:11.813Z" level=info msg="Workflow update successful" namespace=argo-events phase=Failed resourceVersion=49713004 workflow=example-db6tm
time="2022-06-03T20:18:11.824Z" level=info msg="archiving workflow" namespace=argo-events uid=b2e5b49b-db7d-427c-9859-dec6d546fc40 workflow=example-db6tm
time="2022-06-03T20:18:11.871Z" level=info msg="Queueing Failed workflow argo-events/example-db6tm for delete in 1m0s due to TTL"
apiVersion: v1
items: []
kind: List
metadata:
  resourceVersion: ""
No resources found in argo-events namespace.

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