Type parameter's function properties referencing other properties of the same parameter are broken #60848

namespace round_one {
    // let's start with declaring a function that:
    // - accepts a numeric `primaryProperty`
    // - accepts `dependentProperty` which should be identical to `primaryProperty`
    // - accepts optional `dependentFunctionProperty` which is a function with a parameter based on `primaryProperty`
    declare function define<const obj extends {
        readonly primaryProperty: number
        dependentProperty: obj['primaryProperty']
        dependentFunctionProperty?: (primary: obj['primaryProperty']) => void
    }>(obj: obj): obj 

    // so far everything works as expected
    define( {
        primaryProperty: 11,
        dependentProperty: 11, // no errors
    } )
    define( {
        primaryProperty: 11,
        dependentProperty: 13, // an error
    } )
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentFunctionProperty: () => {}, // no errors if there is no parameter
    } )

    // but when we add a parameter to `dependentFunctionProperty`, it breaks because...
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        // Type '(primary: number) => void' is not assignable to type '(primary: unknown) => void'. 
        // though we didn't state which type we expect in the parameter! and why did `primary` become `unknown`?
        dependentFunctionProperty: (primary) => {
            primary
        },
    } )
}

namespace round_two {
    // if we replace a function property with a method, things get even weirder.
    declare function define<const obj extends {
        readonly primaryProperty: number
        dependentProperty: obj['primaryProperty']
        dependentMethod(primary: obj['primaryProperty']): void
    }>(obj: obj): obj 

    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentMethod(primary) {
            // `primary` is not inferred as `unknown` now, but still is not `11`: it's a `number`
            primary
        },
    } )

    // but we can manually annotate `primary` without any problems
    // which would be impossible for "normal" function signatures expecting `number`
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentMethod(primary: 11) { // no errors
            primary
        },
    } )

    // annotating `primary` with something different than 11 results in an error as well
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentMethod(primary: 12) { // an error
            primary
        },
    } )
}

namespace round_three {
    // now we get to the weirdest part of the problem.
    // accidentally i've discovered that simply repeating
    // the declaration of `define` makes typescript behave almost correctly
    declare function define<const obj extends {
        readonly primaryProperty: number
        dependentProperty: obj['primaryProperty']
        dependentFunctionProperty?: (primary: obj['primaryProperty']) => void
    }>(obj: obj): obj
    declare function define<const obj extends {
        readonly primaryProperty: number
        dependentProperty: obj['primaryProperty']
        dependentFunctionProperty?: (primary: obj['primaryProperty']) => void
    }>(obj: obj): obj 

    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        // no errors here, but hovering over `primary` shows `number` as if we were declaring `dependentFunctionProperty` as a method
        dependentFunctionProperty: (primary) => {
            primary
        },
    } )

    // annotating `primary` works like in `dependentMethod` as well
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentFunctionProperty: (primary: 11) => { // no errors
            primary
        },
    } )
    define( {
        primaryProperty: 11,
        dependentProperty: 11,
        dependentFunctionProperty: (primary: 12) => { // an error
            primary
        },
    } )
}