Error output: difficult to understand multistorey errors

Incompatible type

var foo = {a: {b: {c: {d: 3}}}};
var bar: {a: {b: {c: {d: {e: number}}}}} = foo;

Instead of

Type '{ a: { b: { c: { d: number; }; }; }; }' is not assignable to type '{ a: { b: { c: { d: { e: number; }; }; }; }; }'.
  Types of property 'a' are incompatible.
    Type '{ b: { c: { d: number; }; }; }' is not assignable to type '{ b: { c: { d: { e: number; }; }; }; }'.
      Types of property 'b' are incompatible.
        Type '{ c: { d: number; }; }' is not assignable to type '{ c: { d: { e: number; }; }; }'.
          Types of property 'c' are incompatible.
            Type '{ d: number; }' is not assignable to type '{ d: { e: number; }; }'.
              Types of property 'd' are incompatible.
                Type 'number' is not assignable to type '{ e: number; }'.

Print something like that

Type '{ a: { b: { c: { d: number; }; }; }; }' is not assignable to type '{ a: { b: { c: { d: { e: number; }; }; }; }; }'.
  Property 'a.b.c.d: number' is not assignable to 'a.b.c.d: {...}'

Missing property

var foo = {a: {b: {c: {d: 3}}}};
var bar: {a: {b: {c: {d: number, e: number}}}} = foo;

Type '{ a: { b: { c: { d: number; }; }; }; }' is not assignable to type '{ a: { b: { c: { d: number; e: number; }; }; }; }'.
  Types of property 'a' are incompatible.
    Type '{ b: { c: { d: number; }; }; }' is not assignable to type '{ b: { c: { d: number; e: number; }; }; }'.
      Types of property 'b' are incompatible.
        Type '{ c: { d: number; }; }' is not assignable to type '{ c: { d: number; e: number; }; }'.
          Types of property 'c' are incompatible.
            Type '{ d: number; }' is not assignable to type '{ d: number; e: number; }'.
              Property 'e' is missing in type '{ d: number; }'.

vs

Type '{ a: { b: { c: { d: number; }; }; }; }' is not assignable to type '{ a: { b: { c: { d: number; e: number; }; }; }; }'.
  Property 'a.b.c.e: number' is missing

Incompatible function parameter

var foo = {a: {b: {c: {d(y: number, x: string, z: number) {}}}}};
var bar: {a: {b: {c: {d(y: number, x: number, z: number):void}}}} = foo;

Type '{ a: { b: { c: { d(y: number, x: string, z: number): void; }; }; }; }' is not assignable to type '{ a: { b: { c: { d(y: number, x: number, z: number): void; }; }; }; }'.
    Parameter 'a.b.c.d(...,x: string,...)' is not compatible to 'a.b.c.d(...,x: number,...)'

Incompatible function return

var foo = {a: {b: {c: {d(x: number) {}}}}};
var bar: {a: {b: {c: {d(x: number):Date}}}} = foo;

Type '{ a: { b: { c: { d(x: number): void; }; }; }; }' is not assignable to type '{ a: { b: { c: { d(x: number): Date; }; }; }; }'.      
   Return type of 'a.b.c.d(...): void' is not compatible to 'a.b.c.d(...): Date'

Start with the incompatible-type, missing-property, incompatible-parameter, and incompatible-return examples in the issue. Trace how TypeScript currently formats these nested diagnostics, then compare the output with the requested property-path format; done means the examples report concise paths while preserving the relevant incompatibility details.