Upgrading from 0.25.24 t0 0.27.8 - issues with Type.Intersect

[tgilino]

We recently found the need to update to 0.26+ due to needing Type.BigInt however we are now facing issues related to (I believe) the breaking change documented in the 0.26.0 changelog about Intersect. It states that we can use Type.Composite for backwards compatibility, but after updating (compilation is ok), we are getting runtime errors of the form

TypeExtends: Unknown left type operand 'Unsafe'

An example of what we were previously using in 0.25.24:

Type.Union([
	Type.Object({
		A: Type.String({ description: 'A' }),
	}),
	Type.Object({
		B: Type.String({ description: 'B' }),
	}),
	Type.Pick(
		Type.Intersect([
			ATypeWithALotOfProperties,
			Type.Object({
				C: Type.Optional(CTypeEnumSchema),
			}),
		]),
		[A List of Properties ],
	),
])

Kind of at a loss where to go from here. I also saw in the examples section an IntersectLegacy but I wasn't able to figure out how to get it recognized by type builder. Any help would be very much appreciated!

[sinclairzx81]

@tgilino Hi,

Yeah, there has been quite a few changes from 0.26.0 with respect to intersection types. The composite type is provided as a fallback, however to keep composite inline with the new type model, this type also performs an X extends Y per property check to determine if overlapping properties would yield TNever. This check is only supported for known types (not unsafe types, hence the Extends error you see). I may investigate ways to relax this check in future revisions.

IntersectLegacy Type

You can just import the intersect example from here and replace Type.Intersect for IntersectLegacy

import { IntersectLegacy } from './intersect-legacy' // you will need to copy and paste file into your project

// ...

Type.Pick(
  IntersectLegacy([  // Just replace instances of Type.Intersect with IntersectLegacy 
    TypeWithALotOfProperties,
    Type.Object({
      C: Type.Optional(CTypeEnumSchema),
    }),
  ]),
  [A List of Properties ],
),

TypeBuilder with IntersectLegacy Type

If you want to include the legacy intersect type on the type builder, you will need to extend and re export the ExtendedTypeBuilder

import { ExtendedTypeBuilder, ObjectOptions, TObject } from '@sinclair/typebox'
import { IntersectLegacy, TIntersectLegacy } from './legacy/intersect'

export class ApplicationTypeBuilder extends ExtendedTypeBuilder {
  public IntersectLegacy<T extends TObject[]>(objects: [...T], options: ObjectOptions = {}): TIntersectLegacy<T> {
    return IntersectLegacy<T>(objects, options)
  }
}
// re-export the new type builder
export const Type = new ApplicationTypeBuilder()

Then import the extended application type builder and use as normal.

import { Type } from './application-types'

// ...

Type.Pick(
  Type.IntersectLegacy([  // Now available on TypeBuilder
    TypeWithALotOfProperties,
    Type.Object({
      C: Type.Optional(CTypeEnumSchema),
    }),
  ]),
  [A List of Properties ],
),

Hope this helps
S

[tgilino]

Thanks so much for the prompt reply! Was able to get it working exactly as described.