graphql-typed-client/src/render/common/renderTyping.test.ts

A tool that generates a strongly typed client library for any GraphQL endpoint. The client allows writing GraphQL queries as plain JS objects (with type safety, awesome code completion experience, custom scalar type mapping, type guards and more)

import { GraphQLObjectType, GraphQLSchema } from 'graphql'
import { toClientSchema } from '../../testHelpers/render'
import { renderTyping } from './renderTyping'

let schema: GraphQLSchema

const testCase = (field: string, expected: string, undefinableValues: boolean, undefinableFields: boolean) => {
  const fields = (<GraphQLObjectType>schema.getType('Object')).getFields()
  const actual = renderTyping(fields[field].type, undefinableValues, undefinableFields)
  expect(actual).toBe(expected)
}

describe('renderTyping', () => {
  beforeAll(async () => {
    schema = await toClientSchema(/* GraphQL */ `
      type Object {
        value: Int!
        maybeValue: Int
        valueList: [Int!]!
        maybeValueList: [Int]!
        valueMaybeList: [Int!]
        maybeValueMaybeList: [Int]
        nested: [[[Int!]!]!]!
        maybeNested: [[[Int]]]
      }

      type Query {
        _: Boolean
      }
    `)
  })

  test('nullable', () => {
    testCase('value', ':Int', false, false)
    testCase('maybeValue', ':(Int|null)', false, false)
    testCase('valueList', ':Int[]', false, false)
    testCase('maybeValueList', ':(Int|null)[]', false, false)
    testCase('valueMaybeList', ':(Int[]|null)', false, false)
    testCase('maybeValueMaybeList', ':((Int|null)[]|null)', false, false)
    testCase('nested', ':Int[][][]', false, false)
    testCase('maybeNested', ':((((Int|null)[]|null)[]|null)[]|null)', false, false)
  })

  test('undefinable values', () => {
    testCase('value', ':Int', true, false)
    testCase('maybeValue', ':(Int|undefined)', true, false)
    testCase('valueList', ':Int[]', true, false)
    testCase('maybeValueList', ':(Int|undefined)[]', true, false)
    testCase('valueMaybeList', ':(Int[]|undefined)', true, false)
    testCase('maybeValueMaybeList', ':((Int|undefined)[]|undefined)', true, false)
    testCase('nested', ':Int[][][]', true, false)
    testCase('maybeNested', ':((((Int|undefined)[]|undefined)[]|undefined)[]|undefined)', true, false)
  })

  test('undefinable fields', () => {
    testCase('value', ':Int', false, true)
    testCase('maybeValue', '?:(Int|null)', false, true)
    testCase('valueList', ':Int[]', false, true)
    testCase('maybeValueList', ':(Int|null)[]', false, true)
    testCase('valueMaybeList', '?:(Int[]|null)', false, true)
    testCase('maybeValueMaybeList', '?:((Int|null)[]|null)', false, true)
    testCase('nested', ':Int[][][]', false, true)
    testCase('maybeNested', '?:((((Int|null)[]|null)[]|null)[]|null)', false, true)
  })

  test('undefinable fields and values', () => {
    testCase('value', ':Int', true, true)
    testCase('maybeValue', '?:Int', true, true)
    testCase('valueList', ':Int[]', true, true)
    testCase('maybeValueList', ':(Int|undefined)[]', true, true)
    testCase('valueMaybeList', '?:Int[]', true, true)
    testCase('maybeValueMaybeList', '?:(Int|undefined)[]', true, true)
    testCase('nested', ':Int[][][]', true, true)
    testCase('maybeNested', '?:(((Int|undefined)[]|undefined)[]|undefined)[]', true, true)
  })
})