modeling-app/src/lang/queryAst/getIdentifiersInProgram.test.ts

import { assertParse, initPromise } from 'lang/wasm'
import { getIdentifiersInProgram } from './getIndentifiersInProgram'

function identifier(name: string, start: number, end: number) {
  return {
    type: 'Identifier',
    name,
    start,
    end,
    commentStart: start,
  }
}

beforeAll(async () => {
  await initPromise
})

describe(`getIdentifiersInProgram`, () => {
  it(`finds no identifiers in an empty program`, () => {
    const identifiers = getIdentifiersInProgram(assertParse(''))
    expect(identifiers).toEqual([])
  })
  it(`finds a single identifier in an expression`, () => {
    const identifiers = getIdentifiersInProgram(assertParse('55 + a'))
    expect(identifiers).toEqual([identifier('a', 5, 6)])
  })
  it(`finds multiple identifiers in an expression`, () => {
    const identifiers = getIdentifiersInProgram(assertParse('a + b + c'))
    expect(identifiers).toEqual([
      identifier('a', 0, 1),
      identifier('b', 4, 5),
      identifier('c', 8, 9),
    ])
  })
  it(`finds all the identifiers in a normal program`, () => {
    const program = assertParse(`x = 5 + 2
y = x * 2
z = y + 1`)
    const identifiers = getIdentifiersInProgram(program)
    expect(identifiers).toEqual([
      identifier('x', 14, 15),
      identifier('y', 24, 25),
    ])
  })
})