Version

3.0.0

Reproduction link

https://github.com/microsoft/TypeScript/pull/40156/files#diff-3ff86ade791953efc13be67665963d94

Steps to reproduce

Based on the TS user test dockerfile:

yarn add typescript@next --exact --dev --ignore-scripts -W
yarn
npm run build --production -- --types

What is expected?

No compile error.

What is actually happening?

Compile error:

Error: /vue-next/packages/reactivity/src/collectionHandlers.ts(24,3): semantic error TS2322: Type 'T | DeepReadonly<UnwrapNestedRefs<T & Record<any, any>>>' is not assignable to type 'T'.
  'T | DeepReadonly<UnwrapNestedRefs<T & Record<any, any>>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
    Type 'DeepReadonly<UnwrapNestedRefs<T & Record<any, any>>>' is not assignable to type 'T'.
      'DeepReadonly<UnwrapNestedRefs<T & Record<any, any>>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
        Type '(undefined & UnwrapNestedRefs<T & Record<any, any>>) | (null & UnwrapNestedRefs<T & Record<any, any>>) | ... 10 more ... | (UnwrapNestedRefs<...> extends Map<...> ? ReadonlyMap<...> : UnwrapNestedRefs<...> extends ReadonlyMap<...> ? ReadonlyMap<...> : UnwrapNestedRefs<...> extends WeakMap<...> ? WeakMap<...> : Unwra...' is not assignable to type 'T'.
          '(undefined & UnwrapNestedRefs<T & Record<any, any>>) | (null & UnwrapNestedRefs<T & Record<any, any>>) | ... 10 more ... | (UnwrapNestedRefs<...> extends Map<...> ? ReadonlyMap<...> : UnwrapNestedRefs<...> extends ReadonlyMap<...> ? ReadonlyMap<...> : UnwrapNestedRefs<...> extends WeakMap<...> ? WeakMap<...> : Unwra...' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
            Type 'undefined & UnwrapNestedRefs<T & Record<any, any>>' is not assignable to type 'T'.
              'undefined & UnwrapNestedRefs<T & Record<any, any>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
                Type 'DeepReadonly<Ref<any> & T & Record<any, any>> | DeepReadonly<UnwrapRef<T & Record<any, any>>>' is not assignable to type 'T'.
                  'DeepReadonly<Ref<any> & T & Record<any, any>> | DeepReadonly<UnwrapRef<T & Record<any, any>>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
                    Type 'DeepReadonly<UnwrapRef<T & Record<any, any>>>' is not assignable to type 'T'.
                      'DeepReadonly<UnwrapRef<T & Record<any, any>>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
                        Type '(undefined & UnwrapRef<T & Record<any, any>>) | (null & UnwrapRef<T & Record<any, any>>) | (string & UnwrapRef<T & Record<any, any>>) | ... 9 more ... | (UnwrapRef<...> extends Map<...> ? ReadonlyMap<...> : UnwrapRef<...> extends ReadonlyMap<...> ? ReadonlyMap<...> : UnwrapRef<...> extends WeakMap<...> ? WeakMap<......' is not assignable to type 'T'.
                          '(undefined & UnwrapRef<T & Record<any, any>>) | (null & UnwrapRef<T & Record<any, any>>) | (string & UnwrapRef<T & Record<any, any>>) | ... 9 more ... | (UnwrapRef<...> extends Map<...> ? ReadonlyMap<...> : UnwrapRef<...> extends ReadonlyMap<...> ? ReadonlyMap<...> : UnwrapRef<...> extends WeakMap<...> ? WeakMap<......' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
                            Type 'undefined & UnwrapRef<T & Record<any, any>>' is not assignable to type 'T'.
                              'undefined & UnwrapRef<T & Record<any, any>>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.
                                Type 'Readonly<unknown>' is not assignable to type 'T'.
                                  'Readonly<unknown>' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'unknown'.

It is basically the worst error. I am sorry.

I have a workaround ready.