Bug Report

🔎 Search Terms

partial nested object type

🕗 Version & Regression Information

• This changed between versions 4.5.5 and 4.6.4. It reproduces in all versions since 4.6.4 (including nightly)

⏯ Playground Link

Playground link with relevant code

💻 Code

type OverridesInput = {
    someProp?: 'A' | 'B'
}

const foo: Partial<{something: any}> & {variables: {
    overrides?: OverridesInput;
} & Partial<{
    overrides?: OverridesInput;
}>} = {variables: {overrides: false}};

🙁 Actual behavior

There is no error on the overrides field in the object. Changing the type of foo slightly (removing one of the intersections) causes the error to appear correctly, but this unique combination of types produces no error. Does not matter what the contents of OverridesInput is, nor what the content inside the outer partial (currently {something: any}) is. Additionally, the following all produce the error correctly:

type OverridesInput = {
    someProp?: 'A' | 'B'
}

const foo: {variables: {
    overrides?: OverridesInput;
} & Partial<{
    overrides?: OverridesInput;
}>} = {variables: {overrides: false}};

type OverridesInput = {
    someProp?: 'A' | 'B'
}

const foo: Partial<{something: any}> & {variables: {
    overrides?: OverridesInput;
}} = {variables: {overrides: false}};

type OverridesInput = {
    someProp?: 'A' | 'B'
}

const foo: Partial<{something: any}> & {variables: Partial<{
    overrides?: OverridesInput;
}>} = {variables: {overrides: false}};

🙂 Expected behavior

There should be an error on the overrides field of the object since false is not assignable to OverridesInput | undefined.