Compare feature

[snatvb]

Feature of #1497

Classes

Added "class" property to detect that object is class

Classes forbidden to compare because there is a lot of deep cases that might leads to bug with prototypes.

Extends MetadataCollection

Added find method of type for objects. I think it's good idea to have possibility to get ts.Type by any Metadata.

It requires in my case, because metadata doesn't cover this methods declarations:

type Foo {
  bar(): void
}

I've noticed that it's hard to compare unions:

type Foo = { foo: number } 
type Bar = { bar?: number }
type Union = Foo | Bar

const a = { foo: 1 }
const b = { foo: 2 }

console.assert(
  a === b || (
    a.foo === b.foo
  ) || (
    a.bar === b.bar
  )
)

This will be true, because after fail on foo prop, a.bar === b.bar because undefined === undefined

And this unions a lot of corner cases. I just forbidden it. Left only for primitive types.

Development & Test Environment

I've faced with problem that tests take too much time. I've added possibility to add flag that will filter tests by folder.

pnpm dev --folder=compare.equals

Also added watch mode for root:

pnpm dev