Allow branded types in eventType schemas

[amh4r]

Allow branded types in eventType schemas. Previously, they would cause a type error because we considered them a "transform".

We intentionally don't have StandardSchema transform support. But our check for the existence of a transform (input and output types differ) was too coarse-grained. It errored on branded types as well, even though branded types don't cause a runtime transformation.

https://linear.app/inngest/issue/EXE-1559

---

Note

This PR fixes a false-positive transform error for Zod branded types by introducing StripSymbolKeys<T> to remove symbol-keyed properties before comparing schema input/output types in AssertNoTransform.

^{Written by Mendral for commit da45a45.}

[linear]

EXE-1559 [BUG] Branded types incorrectly flagged as transforms

[changeset-bot]

🦋 Changeset detected

Latest commit: da45a45

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

This PR includes changesets to release 1 package

Name	Type
inngest	Patch

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[mendral-app]

High risk — 1 issue in 1 file

StripSymbolKeys<T> has no base case for primitives — StripSymbolKeys<string> and StripSymbolKeys<number> both resolve to {}, making IsEqualIgnoringBrands<string, number> return true. This means a schema with .transform(Number) (string→number) would silently bypass the transform guard, defeating the entire purpose of AssertNoTransform.

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.

<assessment>
`StripSymbolKeys<T>` has no base case for primitives — `StripSymbolKeys<string>` and `StripSymbolKeys<number>` both resolve to `{}`, making `IsEqualIgnoringBrands<string, number>` return `true`. This means a schema with `.transform(Number)` (string→number) would silently bypass the transform guard, defeating the entire purpose of `AssertNoTransform`.
</assessment>

<file name="packages/inngest/src/components/triggers/triggers.ts">
<issue location="packages/inngest/src/components/triggers/triggers.ts:208">
Missing base case for primitives causes `StripSymbolKeys<string>` and `StripSymbolKeys<number>` to both resolve to `{}`, so `IsEqualIgnoringBrands<string, number>` returns `true` and transforms on primitive fields are silently allowed.
</issue>
</file>

_{Tag @mendral-app with feedback or questions. View session}

[mendral-app]

bug (P0): Missing base case for primitives causes StripSymbolKeys<string> and StripSymbolKeys<number> to both resolve to {}, so IsEqualIgnoringBrands<string, number> returns true and transforms on primitive fields are silently allowed.

Suggested change

Suggested change

	type StripSymbolKeys<T> = {
	[K in keyof T as K extends symbol ? never : K]: StripSymbolKeys<T[K]>;
	};
	type StripSymbolKeys<T> = T extends object
	? { [K in keyof T as K extends symbol ? never : K]: StripSymbolKeys<T[K]> }
	: T;

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At packages/inngest/src/components/triggers/triggers.ts, line 208:

<issue>
Missing base case for primitives causes `StripSymbolKeys<string>` and `StripSymbolKeys<number>` to both resolve to `{}`, so `IsEqualIgnoringBrands<string, number>` returns `true` and transforms on primitive fields are silently allowed.
</issue>