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workflow:validate crashes with "Cannot read properties of undefined (reading 'const')" when the published schema has a job entry without properties.type

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Since Sep 30, 2026.

  • #4505 by @douglowder — closed without merging

Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
82/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
typescript
Domain
cli

Research direction

Start in build/commandUtils/workflow/validation.js at jobTypesFromWorkflowSchema and its call from validateWorkflowJobTypes. Reproduce with eas workflow:validate .eas/workflows/build-preview.yml --non-interactive, or use EXPO_TESTING_WORKFLOW_SCHEMA_PATH with the schema containing the catch-all job entry. Done means the validator no longer throws and validates the unchanged workflow successfully.

Written by the indexing model from the issue text.

Description

issue accepted

Summary

eas workflow:validate fails for every workflow file with:

- Validating the workflow YAML file…
✖ Workflow configuration YAML is not valid.
Error: Cannot read properties of undefined (reading 'const')

The failure happens before any workflow is validated, so it is not caused by the workflow content. It reproduces on a workflow that a previous CLI release reported as valid.

Cause

eas workflow:validate fetches the published workflow schema from GET /v2/workflows/schema and then builds its job-type allowlist in build/commandUtils/workflow/validation.js:

function jobTypesFromWorkflowSchema(workflowJsonSchema) {
  return workflowJsonSchema?.properties?.jobs?.additionalProperties?.anyOf.map(
    (props) => props.properties.type.const,
  );
}

validateWorkflowJobTypes calls this before validateWorkflowStructure, so a TypeError here aborts validation entirely.

The published schema now also contains a catch-all job entry that has no properties.type (its shape is name/if/… plus additionalProperties, used for job types outside the named set). Reading props.properties.type.const on that entry throws the observed TypeError.

Entries 0-17 of anyOf all carry properties.type.const (build, custom, deploy, fingerprint, get-build, maestro-cloud, maestro, require-approval, apple-device-registration-request, submit, testflight, update, slack, doc, repack, github-comment, branch-delete, update-rollout); the additional entry does not.

Reproduction

Any project with a workflow file:

eas workflow:validate .eas/workflows/build-preview.yml --non-interactive

Checked versions: 22.6.0, 23.0.0, 24.0.0, 24.4.0, 24.8.0 (latest) — all contain the same expression and all fail.

Workaround

Point the validator at a copy of the schema without the catch-all entry, using the existing hook in fetchWorkflowSchemaAsync:

EXPO_TESTING_WORKFLOW_SCHEMA_PATH=/path/to/schema-without-catch-all.json \
  eas workflow:validate .eas/workflows/build-preview.yml --non-interactive

With that entry removed the same CLI reports the unmodified workflow as valid, so the workflow content itself is fine.

Suggested fix

Collect job types defensively, ignoring entries that do not declare one:

return (workflowJsonSchema?.properties?.jobs?.additionalProperties?.anyOf ?? [])
  .map((props) => props?.properties?.type?.const)
  .filter((type) => typeof type === 'string');

Ideally the catch-all entry would also be distinguishable without relying on its position in anyOf.

Dominant language
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Merged PRs (30d)
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