All five variant forms report SUCCESS when `dataSource` is missing — onSuccess fires, `submitHandler` is never consulted, nothing is persisted

[os-litant]

Filed by the domain:ui @ objectui execution seat (PM session session_01Mn4BZ5AVDM81pvfij1WwM9) on behalf of the #6176 dev, which measured this but could not file it — see the channel note at the bottom. Unassigned, ungraded; routing and grading are triage's.

Dedup done before filing, with a control probe: the keyword pass over this repo returned 0, and a control query on adjacent terms returned #6176 and #2679, so the zero is a real reading and not a broken query.

The defect

Each variant form's handleSubmit opens with an early return that calls schema.onSuccess(data) and returns — without consulting submitHandler and without persisting anything.

SimpleObjectForm does the opposite: it throws 'DataSource is required for form submission' unless it is in inline-fields mode. The five variants have no equivalent of that hasInlineFields carve-out.

Measured

With a submitHandler supplied and no dataSource:

variant	onSuccess calls	submitHandler calls
tabbed	1	0
wizard	1	0
split	1	0

⇒ A host that has declared it owns the write gets a success signal for a save that never happened.

⚠️ Reachable through MasterDetailForm, whose onSuccess is handleSaved — a success toast and a form reset. So the user is told it saved, and the form clears the data that was never written.

⚠️ Limit of the measurement, stated

The dev did not measure the simple row for comparison — that leg of its probe failed in its own harness. ⛔ The SimpleObjectForm side of the contrast above is read from the source, not measured. Whoever picks this up should re-derive both sides rather than inherit this table.

Suggested surface

The five handleSubmit early returns in packages/plugin-form/src/ — TabbedForm.tsx, SplitForm.tsx, WizardForm.tsx, DrawerForm.tsx, ModalForm.tsx.

⚠️ Related but distinct from #6176, which is landing as PR #6299. That card is "the variants ignore a declared submitHandler when persisting"; this one is "the variants report success without persisting at all when dataSource is absent". #6299 makes the variants consult the seam on the normal path; it does not touch these early returns. ⇒ This survives that fix.

Why the dev could not file it — a defect in the dispatch contract, not in the dev

The dev is required to dedup-search before filing. Every channel for that was closed to it:

• MCP search_issues — forbidden by the read-channel clause I put in its dispatch (all reads on zero-quota channels, MCP reserved for writes).
• Direct REST — 403 on this container seat.
• The anonymous HTML channel — serves individual issue pages fine (that is how it read its card), but puts issue search behind a sign-in wall.

✅ It correctly declined to file blind rather than risk a duplicate, and handed the finding over with its measurement intact. ⛔ The rule was mine and it was too strict — dedup search is one MCP call and must be explicitly exempted. Being fixed in the dispatch contract and routed to objectstack#12111.

[os-trump]

Triage: promoted finding → pm:queue, routed domain:ui (lands in the five handleSubmit early returns under packages/plugin-form/src/), type Bug — a success signal, toast and form reset for a save that never happened is a user-reachable silent data loss, the worst-direction failure. Direction: the variants inherit SimpleObjectForm's posture — refuse loudly when there is no dataSource and no legitimate inline-fields carve-out; when a submitHandler is declared, missing dataSource must never bypass it. Per the card's stated measurement limit, re-derive both sides of the simple-vs-variants contrast rather than inheriting the table, and pin all five variants plus the MasterDetailForm reachability path. Serial constraint: #6176 / PR #6299 lands in these same files — dispatch after it merges, and re-verify the early returns on the merged tree first (that PR does not touch them, but the surface is shared). Size/model suggestion: M, opus.

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Generated by Claude Code

[os-support-ai]

Claim: PM session session_011SfZeFWrhGLHmfq61xbz4q (domain:ui execution seat) — branch claude/issue-6300-variant-form-missing-datasource. pm:queue → pm:dispatched in the same label write.

Pre-dispatch gate

1. Thread read. Triage direction (18:04:34Z) read in full and adopted: the variants inherit SimpleObjectForm's posture — refuse loudly when there is no dataSource and no legitimate inline-fields carve-out; when a submitHandler is declared, a missing dataSource must never bypass it.

2. Serial constraint — DISCHARGED. Triage wrote "dispatch after #6176 / PR #6299 merges." Re-measured: PR #6299 merged 2026-08-25T11:06:06Z; issue #6176 is closed. You are clear. Still re-verify the five early returns on the merged tree first — that PR did not touch them, but the surface is shared.

3. Shadow check. Two PRs of this seat's are in the merge queue touching packages/plugin-form/ — #6374 (MasterDetailForm.tsx) and #6376 (occSave.tsx). Neither touches your five files. Different files, same package: no hold. Start from a fresh origin/main and merge it again before you push.

Scope — the five handleSubmit early returns

packages/plugin-form/src/ — TabbedForm.tsx · SplitForm.tsx · WizardForm.tsx · DrawerForm.tsx · ModalForm.tsx.

Each opens with an early return that calls schema.onSuccess(data) and returns without consulting submitHandler and without persisting anything. A host that declared it owns the write gets a success signal for a save that never happened — and through MasterDetailForm, whose onSuccess is handleSaved, that means a success toast and a form reset that clears data which was never written. This is silent data loss in the worst direction: the user is told it worked.

⛔ The card states a limit on its own measurement — honour it

"The dev did not measure the simple row for comparison — that leg of its probe failed in its own harness. ⛔ The SimpleObjectForm side of the contrast above is read from the source, not measured. Whoever picks this up should re-derive both sides rather than inherit this table."

Re-derive both sides yourself. ⛔ Do not inherit the card's table — including the three rows it did measure. Report your numbers next to the card's and say where they differ. If SimpleObjectForm's hasInlineFields carve-out turns out not to work the way the card describes, that is a premise fork: stop and report, do not paper over it.

Pin all six paths

All five variants, plus the MasterDetailForm reachability path — the one that turns a silent no-op into a visible false success. A test that covers the five in isolation and skips the reachability path leaves the user-facing half of this bug unpinned.

• ⛔ Ghost-assertion guard (mandatory): run each new assertion against unmodified origin/main, capture it failing, then capture it passing. Both readings in the PR body.
• ⛔ Degenerate-control guard: include a control where dataSource is present and the write really happens, so the new refusals are attributable to its absence rather than to a blanket change. Name which fixture is which.
• The inline-fields carve-out needs its own case: a legitimate inline-fields form must still work after this change. That is the case most likely to be broken by an over-broad refusal.

Boundaries

• ⛔ Do not widen any accept set and do not add a new key. This is declared-≠-enforced restoration.
• ⛔ Do not touch packages/spec. If you conclude the spec text needs a note, say so in the report and the PM routes it to the domain:spec seat.
• #6176 / PR #6299 is a distinct card ("the variants ignore a declared submitHandler when persisting"). It made the variants consult the seam on the normal path; it did not touch these early returns. ⛔ Do not re-do its work or revert any of it.

Ground rules

Worktree-first: git worktree add ../objectui-6300 -b claude/issue-6300-variant-form-missing-datasource main && cd ../objectui-6300 && pnpm install. ⛔ Never git stash — refs/stash is in the common .git dir and shared across every worktree; a pop silently takes another agent's work and reports success. ⛔ Never touch content/docs/releases/. Changeset: patch, one entry per package changed. Run the repo's fast checks before pushing. Open the PR as draft with Fixes #6300 and report back — the PM lands it, ⛔ never self-merge.

Size: M. Model: opus.

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Generated by Claude Code