feat(wrangler): introspect workflow with test harness

[edmundhung]

Fixes n/a.

This adds Workflow introspection to createTestHarness()

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• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: it will be covered with the rest of the test harness docs changes.

A picture of a cute animal (not mandatory, but encouraged)

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[changeset-bot]

🦋 Changeset detected

Latest commit: 4b12b7f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 6 packages

Name	Type
@cloudflare/vitest-pool-workers	Minor
miniflare	Patch
wrangler	Minor
@cloudflare/deploy-helpers	Patch
@cloudflare/pages-shared	Patch
@cloudflare/vite-plugin	Patch

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[workers-devprod]

Codeowners approval required for this PR:

• @cloudflare/workflows
• @cloudflare/wrangler

Show detailed file reviewers

• .changeset/sharp-workflows-wait.md: [@cloudflare/wrangler]
• .changeset/soft-workflows-smile.md: [@cloudflare/wrangler]
• fixtures/vitest-pool-workers-examples/workflows/test/integration.test.ts: [@cloudflare/wrangler]
• packages/miniflare/src/workers/workflows/wrapped-binding.worker.ts: [@cloudflare/wrangler]
• packages/vitest-pool-workers/src/worker/workflows.ts: [@cloudflare/wrangler]
• packages/vitest-pool-workers/types/cloudflare-test.d.ts: [@cloudflare/wrangler]
• packages/workflows-shared/src/binding.ts: [@cloudflare/workflows @cloudflare/wrangler]
• packages/workflows-shared/src/introspection.ts: [@cloudflare/workflows @cloudflare/wrangler]
• packages/workflows-shared/src/types.ts: [@cloudflare/workflows @cloudflare/wrangler]
• packages/wrangler/e2e/createTestHarness.test.ts: [@cloudflare/wrangler]
• packages/wrangler/src/api/test-harness.ts: [@cloudflare/wrangler]
• packages/wrangler/tsup.config.ts: [@cloudflare/wrangler]

[ask-bonk]

Review posted successfully to PR #14438.

Summary of my review:

• Verified the PR consolidates Workflow introspection into @cloudflare/workflows-shared and exposes it on createTestHarness() worker handles, replacing the old env-binding Proxy approach with a module-scoped session map in WorkflowBinding.
• Confirmed correct: the get() sync→async breaking change is properly documented in a minor changeset with migration guidance; the "queued" early-return matches instanceStatusName(InstanceStatus.Queued); createBatch tracking correctly flows through create().
• One actionable (low-severity) issue: posted a suggestion on introspection.ts:142 for a potential unhandled promise rejection in WorkflowInstanceIntrospectorHandle — the constructor's modifier promise is only awaited inside modify(), so the new introspectWorkflowInstance flow (which may never call modify()) can leak an unhandled rejection on RPC failure.

github run

[github-actions]

✅ All changesets look good

[pkg-pr-new]

@cloudflare/autoconfig

npm i https://pkg.pr.new/@cloudflare/autoconfig@14438

create-cloudflare

npm i https://pkg.pr.new/create-cloudflare@14438

@cloudflare/deploy-helpers

npm i https://pkg.pr.new/@cloudflare/deploy-helpers@14438

@cloudflare/kv-asset-handler

npm i https://pkg.pr.new/@cloudflare/kv-asset-handler@14438

miniflare

npm i https://pkg.pr.new/miniflare@14438

@cloudflare/pages-shared

npm i https://pkg.pr.new/@cloudflare/pages-shared@14438

@cloudflare/unenv-preset

npm i https://pkg.pr.new/@cloudflare/unenv-preset@14438

@cloudflare/vite-plugin

npm i https://pkg.pr.new/@cloudflare/vite-plugin@14438

@cloudflare/vitest-pool-workers

npm i https://pkg.pr.new/@cloudflare/vitest-pool-workers@14438

@cloudflare/workers-auth

npm i https://pkg.pr.new/@cloudflare/workers-auth@14438

@cloudflare/workers-editor-shared

npm i https://pkg.pr.new/@cloudflare/workers-editor-shared@14438

@cloudflare/workers-utils

npm i https://pkg.pr.new/@cloudflare/workers-utils@14438

wrangler

npm i https://pkg.pr.new/wrangler@14438

commit: 4b12b7f

[devin-ai-integration]

Devin Review found 1 new potential issue.

[devin-ai-integration]

🚩 Operations accumulate across multiple modifyAll calls rather than replacing

Each modifyAll call creates a new WorkflowInstanceModificationRecorder wrapping the same #operations array (packages/workflows-shared/src/introspection.ts:152). Operations pushed by the callback accumulate, and the full array is sent to the remote via unsafeSetIntrospectionOperations, which replaces (session.operations = operations at packages/workflows-shared/src/binding.ts:272). This means a second modifyAll call includes all operations from the first call. Current test usage only calls modifyAll once per introspector, so the accumulation pattern isn't exercised. If a user calls modifyAll twice expecting replacement semantics, they'd get unexpected duplication of operations like disableSleeps. This is a design choice rather than a bug, but the behavior isn't documented.

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[edmundhung]

I think it is the same behavior before this change.