Type alias SpreadDeepObject<T, TCondition, TValue>

Recursively generates a type that mimics spreading object T with object TValue, and replaces (plain) objects within a complex object whose shape matches TCondition.

Example

type DbConfig = {
        host: string
        port: number
        credentials: {
            username: string
            password: string
        }
    }

    type Config = {
        database: DbConfig
        service: {
            gcRun: {
                auth: {
                    username: string
                    password: string
                    key: string
                    prop1: string
                    prop2: string
                }
            }
        }
        dbConfigs: DbConfig[]
        logging: {
            level: string
            format: "json" | "text"
        }
    }

    type Condition = {
        username: string
        password: string
    }

    type NewProperties = {
        encrypted: boolean
        password: number
    }

    // Using SpreadDeepObject to spread NewProperties onto parts of Config that match Condition
    type UpdatedConfig = SpreadDeepObject<Config, Condition, NewProperties>

    // The resulting type would look like this:

    type UpdatedConfigResult = {
        database: {
            host: string
            port: number
            credentials: {
                username: string
                password: number // <-- Replaced
                encrypted: boolean // <-- New property
            }
        }
        service: {
            gcRun: {
                auth: {
                    username: string
                    password: number // <-- Replaced
                    key: string
                    prop1: string
                    prop2: string
                    encrypted: boolean // <-- New property
                }
            }
        }
        dbConfigs: {
            // Also recurses into arrays
            host: string
            port: number
            credentials: {
                username: string
                password: number // <-- Replaced
                encrypted: boolean // <-- New property
            }
        }[]
        logging: {
            level: string
            format: "json" | "text"
        }
    }
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Returns

The modified type.