import { test, expect, describe } from "bun:test"
import { VM } from "#vm"
import { toBytecode } from "#bytecode"
import { toValue } from "#value"

describe("VM scope methods", () => {
  test("pushScope creates isolated child scope", async () => {
    const bytecode = toBytecode([["HALT"]])
    const vm = new VM(bytecode)

    vm.set("x", 42)

    vm.pushScope()

    const xValue = vm.scope.get("x")
    expect(xValue).toEqual({ type: "number", value: 42 })

    vm.set("y", 100)

    expect(vm.scope.get("x")).toEqual({ type: "number", value: 42 })
    expect(vm.scope.get("y")).toEqual({ type: "number", value: 100 })
  })

  test("popScope returns to parent scope and child variables are not accessible", async () => {
    const bytecode = toBytecode([["HALT"]])
    const vm = new VM(bytecode)

    vm.set("x", 42)

    vm.pushScope()
    vm.set("y", 100)

    expect(vm.scope.get("x")).toEqual({ type: "number", value: 42 })
    expect(vm.scope.get("y")).toEqual({ type: "number", value: 100 })

    vm.popScope()

    expect(vm.scope.get("x")).toEqual({ type: "number", value: 42 })

    expect(vm.scope.get("y")).toBeUndefined()
  })
})